SUBELEMENT 6A - GENERAL - [100 EXAM QUESTIONS]SUBELEMENT 6A - GENERAL - [100 EXAM QUESTIONS]

6A16A1AASITOR-ARQ is a common mode of data communications in the maritime service. It is a system based onSITOR-ARQ is a common mode of data communications in the maritime service. It is a system based on transmission bursts and acknowledgements. What is the baud, and interval between the burst transmission bursts and acknowledgements. What is the baud, and interval between the burst transmissions:transmissions: A.100 baud, 240 ms interval A.100 baud, 240 ms interval B.50 baud, 1000 µs interval B.50 baud, 1000 µs interval C.200 baud, 10 ms interval C.200 baud, 10 ms interval D.None of the above D.None of the above

6A26A2DDWeather information is commonly sent by radio in map form by one-way facsimile transmission. Two Weather information is commonly sent by radio in map form by one-way facsimile transmission. Two common parameters which must be set by the receiving station are:common parameters which must be set by the receiving station are: A.Lines-per-inch (LPI), and primary scan direction (PSD) A.Lines-per-inch (LPI), and primary scan direction (PSD) B.Frequency shift (FS), and phase response pattern (PRP) B.Frequency shift (FS), and phase response pattern (PRP) C.Black-mode signal (BMS), and frequency jitter tolerance (FJT) C.Black-mode signal (BMS), and frequency jitter tolerance (FJT) D.Index of cooperation (IOC), and revolutions per minute (RPM) D.Index of cooperation (IOC), and revolutions per minute (RPM)

6A36A3AA2182 kHz is the international radiotelephone distress frequency. It is also used for a calling channel. The2182 kHz is the international radiotelephone distress frequency. It is also used for a calling channel. The authorized mode of emission is H3E (single-sideband full carrier). A3E (double-sideband full carrier) is authorized mode of emission is H3E (single-sideband full carrier). A3E (double-sideband full carrier) is only authorized for equipment:only authorized for equipment: A.Solely intended for distress and safety communications A.Solely intended for distress and safety communications B.Built and sold after the GMDSS implementation date B.Built and sold after the GMDSS implementation date C.Built and sold before the GMDSS implementation date C.Built and sold before the GMDSS implementation date D.Solely intended for ship-to-shore public correspondence D.Solely intended for ship-to-shore public correspondence

6A46A4DDShip's power is generated as 3-phase and is ungrounded. On a delta-wound transformer with 120 VAC Ship's power is generated as 3-phase and is ungrounded. On a delta-wound transformer with 120 VAC line-to-line secondary, what is the voltmeter reading from line to ground:line-to-line secondary, what is the voltmeter reading from line to ground: A.Approx 67 volts for a normal balanced system with no faults A.Approx 67 volts for a normal balanced system with no faults B.0 VAC for a system with that phase faulted to ground B.0 VAC for a system with that phase faulted to ground C.120 VAC when another phase is faulted to ground C.120 VAC when another phase is faulted to ground D.Any of the above D.Any of the above

6A56A5DDWhen passing through areas of static charge, high voltages can accumulate on antennas which are When passing through areas of static charge, high voltages can accumulate on antennas which are insulated from ground. What protects a connected receiver from damage?insulated from ground. What protects a connected receiver from damage? A.Lightning arresters and suppressors A.Lightning arresters and suppressors B.Protection diodes on receiver input B.Protection diodes on receiver input C.Capacitive coupling and static dissipative circuits C.Capacitive coupling and static dissipative circuits D.Any combination of the above D.Any combination of the above6A66A6BB

Vertical shipboard antennas for use in the MF band (410-525 kHz) are often fitted with top-hat loading Vertical shipboard antennas for use in the MF band (410-525 kHz) are often fitted with top-hat loading sections. What is the purpose of these structures?sections. What is the purpose of these structures? A.Provides aerodynamic compensation for stress during high winds A.Provides aerodynamic compensation for stress during high winds B.Permits a physically short antenna to appear electrically longer B.Permits a physically short antenna to appear electrically longer C.Improves the near-field radiated pattern at the expense of the far-field pattern C.Improves the near-field radiated pattern at the expense of the far-field pattern D.Prevents salt build-up on antennas from shunting RF energy to ground D.Prevents salt build-up on antennas from shunting RF energy to ground

6A76A7BBModern reserve transmitters are solid-state designs and transmit using only A2 modulation. When Modern reserve transmitters are solid-state designs and transmit using only A2 modulation. When measuring transmitter center frequency, what precaution must be taken:measuring transmitter center frequency, what precaution must be taken: A.Antenna must be grounded to suppress spurious side-lobes A.Antenna must be grounded to suppress spurious side-lobes B.Modulation must be reduced to zero to eliminate sidebands B.Modulation must be reduced to zero to eliminate sidebands C.Voltage to the PA must be kept at half-value C.Voltage to the PA must be kept at half-value D.Antenna current must be reduced to about 2.5 uA D.Antenna current must be reduced to about 2.5 uA

6A86A8DDVoltage may be expressed by what other expression?Voltage may be expressed by what other expression? A.Difference of potential A.Difference of potential B.IF drop B.IF drop C.Electromotive force C.Electromotive force D.All of the above D.All of the above

6A96A9DDAmperage may also be known by:Amperage may also be known by: A.Electron flow A.Electron flow B.Electron drift B.Electron drift C.Electric current flow C.Electric current flow D.All of the above D.All of the above

6A106A10DDFactors which determine the amplitude of the voltage induced in a conductor which is cutting magnetic Factors which determine the amplitude of the voltage induced in a conductor which is cutting magnetic lines of force:lines of force: A.Flux density A.Flux density B.Velocity that the conductor cuts the magnetic lines of force B.Velocity that the conductor cuts the magnetic lines of force C.The angle at which the conductor cuts through the magnetic lines of force C.The angle at which the conductor cuts through the magnetic lines of force D.All of the above D.All of the above

6A11 6A11DDAn electrical potential may be generated by:An electrical potential may be generated by: A.Varying a magnetic field through a circuit A.Varying a magnetic field through a circuit B.Chemical action B.Chemical action C.Photo-electric action C.Photo-electric action D.All of the above D.All of the above6A126A12DD

Ohm's law is stated as:Ohm's law is stated as: A.E = IR A.E = IR B.I = E / R B.I = E / R C.R = E / I C.R = E / I D.All of the above D.All of the above

6A136A13CCThe unit of electrical power is:The unit of electrical power is: A.Watt A.Watt B.Joule per second B.Joule per second C.Both A & B C.Both A & B D.None of the above D.None of the above

6A146A14BBThe unit of conductance is:The unit of conductance is: A.Ohm A.Ohm B.Mho B.Mho C.Henry C.Henry D.Ampere D.Ampere

6A156A15AAThe unit of inductance is:The unit of inductance is: A.Henry A.Henry B.Joule B.Joule C.Coulomb C.Coulomb D.Ohm D.Ohm

6A166A16BBThe ratio of current through a conductor to the voltage which produces it is:The ratio of current through a conductor to the voltage which produces it is: A.Inductance A.Inductance B.Conductance B.Conductance C.Resistance C.Resistance D.None of the above D.None of the above

6A176A17AAThe product of the number of turns and the current in amperes used to describe relative magnitude is:The product of the number of turns and the current in amperes used to describe relative magnitude is: A.Ampere turns A.Ampere turns B.Joules per second B.Joules per second C.Push-pull convergence C.Push-pull convergence D.Dissipation collection D.Dissipation collection

6A186A18BB

The property of a conductor or coil which causes a voltage to be developed across its terminals when the The property of a conductor or coil which causes a voltage to be developed across its terminals when the number of magnetic lines of force in the circuit or coil is changed is:number of magnetic lines of force in the circuit or coil is changed is: A.Capacitance A.Capacitance B.Inductance B.Inductance C.Conductance C.Conductance D.None of the above D.None of the above

6A196A19AAThe charge of electricity which passes a given point in one second when a current of one ampere is The charge of electricity which passes a given point in one second when a current of one ampere is flowing is:flowing is: A.Coulomb A.Coulomb B.Joule B.Joule C.Watt C.Watt D.None of the above D.None of the above

6A206A20AAC = capacity in farads. Q = the measure of the quantity of charge of electricity in Coulombs. E = the C = capacity in farads. Q = the measure of the quantity of charge of electricity in Coulombs. E = the applied voltage. So Q = CE:applied voltage. So Q = CE: A.Determines the quantity of charge in a capacitor A.Determines the quantity of charge in a capacitor B.Determines the Q of a circuit B.Determines the Q of a circuit C.Both A & B C.Both A & B D.None of the above D.None of the above

6A216A21DDResistance is:Resistance is: A.The quantity which determines power loss or dissipation A.The quantity which determines power loss or dissipation B.The factor of proportionality between voltage and current B.The factor of proportionality between voltage and current C.Measured in ohms C.Measured in ohms D.All of the above D.All of the above

6A226A22AAThe unit of AC impedance in a circuit is:The unit of AC impedance in a circuit is: A.Ohm A.Ohm B.Mho B.Mho C.Joule C.Joule D.None of the above D.None of the above

6A236A23DDThe unit of capacitance is:The unit of capacitance is:

A.Farad A.Farad B.Microfarad B.Microfarad C.Coulomb C.Coulomb D.A & B D.A & B

6A246A24CCDecibel is:Decibel is: A.The unit used to express the ratio between two sound power levels A.The unit used to express the ratio between two sound power levels B.The unit used to express the ratio between two electrical power levels B.The unit used to express the ratio between two electrical power levels C.Both A & B C.Both A & B D.None of the above D.None of the above

6A256A25CCWhat factors determine the charge stored in a capacitor?What factors determine the charge stored in a capacitor? A.Capacitance of the capacitor A.Capacitance of the capacitor B.The applied voltage B.The applied voltage C.Both A & B C.Both A & B D.None of the above D.None of the above

6A266A26DDOhm's law for AC circuits when I = amperes, E = volts, Z = impedance in volts is:Ohm's law for AC circuits when I = amperes, E = volts, Z = impedance in volts is: A.I = E/Z A.I = E/Z B.E = IZ B.E = IZ C.Z= Z/I C.Z= Z/I D.All of the above D.All of the above

6A276A27AAThe formula for determining the power in a DC circuit when the voltage and resistance are known is:The formula for determining the power in a DC circuit when the voltage and resistance are known is: A.P = ( E squared) R A.P = ( E squared) R B.P = EI B.P = EI C.P = ( I squared) R C.P = ( I squared) R D.PF = W/IE D.PF = W/IE

6A28 6A28BBThe formula for finding power in a DC circuit when current and resistance are known:The formula for finding power in a DC circuit when current and resistance are known: A.P = IE A.P = IE B.P = ( I Squared) R B.P = ( I Squared) R C.PF = W/IE C.PF = W/IE D.None of the above D.None of the above

6A296A29AAThe formula for finding power in a DC circuit when current and voltage are known:The formula for finding power in a DC circuit when current and voltage are known: A.P = EI A.P = EI

B.P = ( I squared ) R B.P = ( I squared ) R C.PF = W/IE C.PF = W/IE D.None of the above D.None of the above

6A306A30AAThe prefix " kilo " means:The prefix " kilo " means: A.To multiply by 1000 whatever quantity follows A.To multiply by 1000 whatever quantity follows B.To divide by 1000 whatever quantity follows B.To divide by 1000 whatever quantity follows C.To add 1000 to whatever quantity follows C.To add 1000 to whatever quantity follows D.None of the above D.None of the above

6A316A31AAThe prefix " micro " means:The prefix " micro " means: A.Divide by 1,000,000 whatever quantity follows A.Divide by 1,000,000 whatever quantity follows B.Multiply by 1,000,000 whatever quantity follows B.Multiply by 1,000,000 whatever quantity follows C.Add 1,000,000 to whatever quantity follows C.Add 1,000,000 to whatever quantity follows D.Divide by 1,000 whatever quantity follows D.Divide by 1,000 whatever quantity follows

6A326A32AAThe factor by which the product of volts and amperes must be multiplied to obtain true power is:The factor by which the product of volts and amperes must be multiplied to obtain true power is: A.Power factor A.Power factor B.Apparent power B.Apparent power C.Phase angle C.Phase angle D.None of the above D.None of the above

6A336A33AAThe prefix " meg " means:The prefix " meg " means: A.Multiply by 1,000,000 whatever quantity follows A.Multiply by 1,000,000 whatever quantity follows B.Multiply by 100,000 whatever quantity follows B.Multiply by 100,000 whatever quantity follows C.Multiply by 1,000 whatever quantity follows C.Multiply by 1,000 whatever quantity follows D.Divide by 1,000,000 whatever quantity follows D.Divide by 1,000,000 whatever quantity follows

6A34 6A34DDFactors which influence the resistance of a conductor:Factors which influence the resistance of a conductor: A.Cross-sectional area A.Cross-sectional area B.Length B.Length C.Temperature C.Temperature D.All of the above D.All of the above

6A356A35AAHalving the cross-sectional area of a conductor will:Halving the cross-sectional area of a conductor will: A.Double the resistance A.Double the resistance B.Half the resistance B.Half the resistance

C.Not affect the resistance C.Not affect the resistance D.None of the above D.None of the above

6A366A36BBName four conducting materials in order of their conductivity.Name four conducting materials in order of their conductivity. A.Gold, silver, copper, platinum A.Gold, silver, copper, platinum B.Silver, gold, zinc, platinum B.Silver, gold, zinc, platinum C.Silver, copper, zinc, aluminum C.Silver, copper, zinc, aluminum D.Aluminum, zinc, copper, platinum D.Aluminum, zinc, copper, platinum

6A376A37DDGood insulators at radio frequencies are:Good insulators at radio frequencies are: A.Pyrex, mica A.Pyrex, mica B.Isolantite, steatite, polyethylene B.Isolantite, steatite, polyethylene C.Rubber, porcelain C.Rubber, porcelain D.A & B D.A & B

6A386A38AAA resistance across which a constant voltage is applied is doubled. What power dissipation will result?A resistance across which a constant voltage is applied is doubled. What power dissipation will result? A.One half A.One half B.One fourth B.One fourth C.Doubled C.Doubled D.None of the above D.None of the above

6A396A39DDThe needle of a magnetic compass when placed within a coil carrying an electric current:The needle of a magnetic compass when placed within a coil carrying an electric current: A.Will tend to become parallel with the axis of the coil A.Will tend to become parallel with the axis of the coil B.Will point to the north pole end of the coil B.Will point to the north pole end of the coil C.Will point to the south pole end of the coil C.Will point to the south pole end of the coil D.A & B D.A & B

6A40 6A40AAElectrical resistance is measured with:Electrical resistance is measured with: A.An ohmmeter A.An ohmmeter B.A wattmeter B.A wattmeter C.An Ammeter C.An Ammeter D.A voltmeter D.A voltmeter

6A416A41AAThe sum of all voltage drops around a simple DC circuit, including the source, is:The sum of all voltage drops around a simple DC circuit, including the source, is: A.Zero A.Zero B.Insignificant B.Insignificant C.Infinite C.Infinite

D.None of the above D.None of the above

6A426A42AAIf a resistance to which a constant voltage is applied is halved, what power dissipation will result?If a resistance to which a constant voltage is applied is halved, what power dissipation will result? A.Doubled A.Doubled B.Halved B.Halved C.Tripled C.Tripled D.Same D.Same

6A436A43DDThe diameter of a conductor six inches long is doubled, what will be the effect on the resistance?The diameter of a conductor six inches long is doubled, what will be the effect on the resistance? A.One-fourth the original value A.One-fourth the original value B.One-half the original value B.One-half the original value C.The resistance varies inversely with the cross-sectional area of the conductor C.The resistance varies inversely with the cross-sectional area of the conductor D.A & C D.A & C

6A446A44AAA minute subdivision of matter having the smallest known unit of negative electrical charge is:A minute subdivision of matter having the smallest known unit of negative electrical charge is: A.Electron A.Electron B.Ion B.Ion C.Gilbert C.Gilbert D.Joule D.Joule

6A456A45DDConductors differ from nonconductors, i.e.:Conductors differ from nonconductors, i.e.: A.There are a large number of free electrons in a good conductor A.There are a large number of free electrons in a good conductor B.There is a small number of free electrons in a non-conductor B.There is a small number of free electrons in a non-conductor C.There is an equal amount of free electrons in a good conductor and in a non-conductor C.There is an equal amount of free electrons in a good conductor and in a non-conductor D.A & B D.A & B

6A466A46DDDirection of flow of DC electricity in a conductor can be determined by:Direction of flow of DC electricity in a conductor can be determined by: A.A magnetic compass and the left hand rule A.A magnetic compass and the left hand rule B.A magnetic compass and the right hand rule B.A magnetic compass and the right hand rule C.Connecting an ammeter with marked polarities in series with the circuit C.Connecting an ammeter with marked polarities in series with the circuit D.A & C D.A & C

6A476A47CCThe difference between electrical power and electrical energy is:The difference between electrical power and electrical energy is: A.Electrical power is the rate of doing work by electricity A.Electrical power is the rate of doing work by electricity B.Electrical energy is the ability to accomplish work by electricity B.Electrical energy is the ability to accomplish work by electricity C.A & B C.A & B D.None of the above D.None of the above

6A486A48CCA positive temperature coefficient means:A positive temperature coefficient means: A.Resistance increases as the temperature increases A.Resistance increases as the temperature increases B.Resistance decreases as the temperature decreases B.Resistance decreases as the temperature decreases C.Both A & B C.Both A & B D.None of the above D.None of the above

6A496A49AAA liquid which is capable of conducting electricity, but undergoes decomposition while doing so is:A liquid which is capable of conducting electricity, but undergoes decomposition while doing so is: A.An electrolyte A.An electrolyte B.A ferromagnetic material under the influence of a magnetizing force B.A ferromagnetic material under the influence of a magnetizing force C.Equal to the ohmic resistance of the circuit C.Equal to the ohmic resistance of the circuit D.None of the above D.None of the above

6A506A50AAThe effective value of an RF current and the heating value of the current are:The effective value of an RF current and the heating value of the current are: A.The same A.The same B.Effective value divided by two equals the heating value B.Effective value divided by two equals the heating value C.Effective value multiplied by two equals the heating value C.Effective value multiplied by two equals the heating value D.None of the above D.None of the above

6A516A51DDOne horsepower is:One horsepower is: A.746 Watts A.746 Watts B.Roughly 3/4 kilowatt B.Roughly 3/4 kilowatt C.Corresponds to lifting 550 pounds at the rate of one foot per second C.Corresponds to lifting 550 pounds at the rate of one foot per second D.All of the above D.All of the above

6A526A52CCWhat factors determine the heat generated in a conductor?What factors determine the heat generated in a conductor? A.It is directly proportional to the resistance A.It is directly proportional to the resistance B.It is directly proportional to the square of the current B.It is directly proportional to the square of the current C.Both A & B C.Both A & B D.None of the above D.None of the above

6A536A53DDWhat is the ratio of peak to average value of a sine wave?What is the ratio of peak to average value of a sine wave? A.1.57 to 1 A.1.57 to 1 B.1 to 0.636 B.1 to 0.636 C.1 to 1 C.1 to 1 D.A & B D.A & B

6A546A54AAWhen the current sine wave in a circuit reaches its peak value before the voltage wave:When the current sine wave in a circuit reaches its peak value before the voltage wave: A.It is said to have a leading power factor A.It is said to have a leading power factor B.It is said to have a lagging power factor B.It is said to have a lagging power factor C.It is said to be in phase C.It is said to be in phase D.None of the above D.None of the above

6A556A55AAAn "harmonic" is:An "harmonic" is: A.A whole multiple of an original frequency A.A whole multiple of an original frequency B.The heating value of an RF current B.The heating value of an RF current C.The internal impedance of a power source C.The internal impedance of a power source D.A multiple of the power factor D.A multiple of the power factor

6A566A56AAAssuming a power source to have a fixed value of internal impedance, maximum power will be Assuming a power source to have a fixed value of internal impedance, maximum power will be transferred to the load when:transferred to the load when: A.The load impedance equals the internal impedance of the source A.The load impedance equals the internal impedance of the source B.The load impedance is higher than the source impedance B.The load impedance is higher than the source impedance C.The load impedance is lower than the source impedance C.The load impedance is lower than the source impedance D.None of the above D.None of the above

6A576A57DDWhen two sine waves of the same frequency do not reach their maximum or minimum values When two sine waves of the same frequency do not reach their maximum or minimum values simultaneously:simultaneously: A.A phase difference exists A.A phase difference exists B.A phase difference does not exist B.A phase difference does not exist C.The sign waves are out of phase C.The sign waves are out of phase D.A & C D.A & C6A586A58CCWhich method may be used to obtain more than one value of voltage from a fixed DC source?Which method may be used to obtain more than one value of voltage from a fixed DC source? A.Use a resistance type voltage divider A.Use a resistance type voltage divider B.Connect voltage regulator tubes of suitable values and tap off the desired output voltage B.Connect voltage regulator tubes of suitable values and tap off the desired output voltage C.Both A & B C.Both A & B D.None of the above D.None of the above

6A596A59

AAThe conductance (G) of a circuit if 6 A flows when 12 VDC is applied is:The conductance (G) of a circuit if 6 A flows when 12 VDC is applied is: A.0.5 mho A.0.5 mho B.1.0 mho B.1.0 mho C.0.25 mho C.0.25 mho D.None of the above D.None of the above

6A606A60AATwo 10 W, 500 ohm resistors in parallel will dissipate how many watts?Two 10 W, 500 ohm resistors in parallel will dissipate how many watts? A.20 watts A.20 watts B.10 watts B.10 watts C.30 watts C.30 watts D.40 watts D.40 watts

6A616A61DDA 20 ohm resistor with a current of 0.25 A passing through it will dissipate how many watts?A 20 ohm resistor with a current of 0.25 A passing through it will dissipate how many watts? A.10 watts A.10 watts B.20 watts B.20 watts C.0.025 watts C.0.025 watts D.1.25 watts D.1.25 watts

6A626A62BBIf the voltage to a circuit is doubled and the resistance is increased to three times the original value, what If the voltage to a circuit is doubled and the resistance is increased to three times the original value, what will be the final current?will be the final current? A.1/3 the original current A.1/3 the original current B.2/3 the original current B.2/3 the original current C.3 times the original current C.3 times the original current D.None of the above D.None of the above

6A636A63AAIf a vacuum tube with a filament rating of 0.25 A and 5 V is operated from a 6 volt battery, what value ofIf a vacuum tube with a filament rating of 0.25 A and 5 V is operated from a 6 volt battery, what value of resistor is necessary?resistor is necessary? A.4 ohms A.4 ohms B.5 ohms B.5 ohms C.10 ohms C.10 ohms D.2 ohms D.2 ohms

6A646A64

AAThe minimum power dissipation rating of a resistor of 20,000 ohms across a potential of 500 V should The minimum power dissipation rating of a resistor of 20,000 ohms across a potential of 500 V should be:be: A.25 watts A.25 watts B.12.5 watts B.12.5 watts C.15 watts C.15 watts D.None of the above D.None of the above

6A656A65AAThe total power dissipation capability of two 10 watt, 500 ohm resistors connected in series is:The total power dissipation capability of two 10 watt, 500 ohm resistors connected in series is: A.20 watts A.20 watts B.10 watts B.10 watts C.5 watts C.5 watts D.None of the above D.None of the above

6A666A66AAWhat is the total power dissipation capability of two 10 watt 500 ohm resistors connected in parallel?What is the total power dissipation capability of two 10 watt 500 ohm resistors connected in parallel? A.20 watts A.20 watts B.40 watts B.40 watts C.5 watts C.5 watts D.None of the above D.None of the above

6A676A67AAWhat is the maximum current carrying capacity of a resistor of 5000 ohms, 200 watts?What is the maximum current carrying capacity of a resistor of 5000 ohms, 200 watts? A.0.2 A A.0.2 A B.1 A B.1 A C.1.2 A C.1.2 A D.None of the above D.None of the above

6A686A68DDWhat is the total resistance of a parallel circuit consisting of a 10 ohm branch and a 25 ohm branch?What is the total resistance of a parallel circuit consisting of a 10 ohm branch and a 25 ohm branch? A.@ ohms A.@ ohms B.10.3 ohms B.10.3 ohms C.7.0 ohms C.7.0 ohms D.7.14 ohms D.7.14 ohms

6A696A69AAThe current through two resistors in series is 3 A. Resistance #1 is 50 ohms, resistance #2 drops 50 V The current through two resistors in series is 3 A. Resistance #1 is 50 ohms, resistance #2 drops 50 V across its terminals. What is the total voltage?across its terminals. What is the total voltage? A.200 V A.200 V B.220 V B.220 V C.110 V C.110 V D.180 V D.180 V

6A706A70

AAAn 18 ohm and a 15 ohm resistor are connected in parallel; a 36 ohm resistor is connected in series with An 18 ohm and a 15 ohm resistor are connected in parallel; a 36 ohm resistor is connected in series with this combination; a 22 ohm resistor is connected in parallel with this total combination. The total currentthis combination; a 22 ohm resistor is connected in parallel with this total combination. The total current is 5 A. What current is flowing in the 15 ohm resistor?is 5 A. What current is flowing in the 15 ohm resistor? A.0.908 A A.0.908 A B.1.000 A B.1.000 A C.1.908 A C.1.908 A D.0.809 A D.0.809 A

6A716A71AAA circuit passes 3 A. The internal resistance of the source is 2 ohms. The total resistance is 50 ohms. A circuit passes 3 A. The internal resistance of the source is 2 ohms. The total resistance is 50 ohms. What is the terminal voltage of the source?What is the terminal voltage of the source? A.150 V A.150 V B.100 V B.100 V C.110 V C.110 V D.240 V D.240 V

6A726A72AAA relay coil has 500 ohms resistance, and operates on 125 mA. What value of resistance should be A relay coil has 500 ohms resistance, and operates on 125 mA. What value of resistance should be connected in series with it to operate from 110 VDC?connected in series with it to operate from 110 VDC? A.380 ohms A.380 ohms B.400 ohms B.400 ohms C.200 ohms C.200 ohms D.None of the above D.None of the above

6A736A73CCGiven: Input power to a receiver is 75 watts. How much power does the receiver consume in 24 hours Given: Input power to a receiver is 75 watts. How much power does the receiver consume in 24 hours of continuous operation?of continuous operation? A.1800 watthours A.1800 watthours B.1.80 kilowatthours B.1.80 kilowatthours C.A & B C.A & B D.None of the above D.None of the above

6A746A74BBThe total reactance when two capacitances of equal value are connected in series is:The total reactance when two capacitances of equal value are connected in series is: A.The product of the two individual reactances in ohms A.The product of the two individual reactances in ohms B.The sum of the two individual reactances in ohms B.The sum of the two individual reactances in ohms C.The difference of the two individual reactances in ohms C.The difference of the two individual reactances in ohms D.None of the above D.None of the above

6A756A75CCA capacitor's charge is stored:A capacitor's charge is stored:

A.Upon the inner surface of the capacitor plates A.Upon the inner surface of the capacitor plates B.As an electrostatic field which exists in the space between the plates B.As an electrostatic field which exists in the space between the plates C.A & B C.A & B D.None of the above D.None of the above

6A766A76DDThe voltage drop across an individual capacitor of a group of capacitors connected in series across an ACThe voltage drop across an individual capacitor of a group of capacitors connected in series across an AC source is:source is: A.Inversely proportional to the ratio of the capacitance of the capacitor being considered A.Inversely proportional to the ratio of the capacitance of the capacitor being considered B.Inversely proportional to the total capacitance of the combination B.Inversely proportional to the total capacitance of the combination C.Directly proportional to the applied voltage across the series combination C.Directly proportional to the applied voltage across the series combination D.All of the above D.All of the above

6A776A77BBWhat is the total capacitance of the capacitors of 3, 5, and 7 microfarad connected in series?What is the total capacitance of the capacitors of 3, 5, and 7 microfarad connected in series? A.14.79 microfarad A.14.79 microfarad B.1.479 microfarad B.1.479 microfarad C.15 microfarad C.15 microfarad D.None of the above D.None of the above

6A786A78AAIf capacitors of 3, 5, and 7 microfarad are connected in parallel, what is the total capacitance?If capacitors of 3, 5, and 7 microfarad are connected in parallel, what is the total capacitance? A.9 microfarad A.9 microfarad B.15 microfarad B.15 microfarad C.10 microfarad C.10 microfarad D.3 microfarad D.3 microfarad

6A796A79BBHow many capacitors of 400 volts and 2 microfarad each would be necessary to obtain a combination How many capacitors of 400 volts and 2 microfarad each would be necessary to obtain a combination rated at 1600 volts and 1.5 microfarad?rated at 1600 volts and 1.5 microfarad? A.10 A.10 B.12 B.12 C.14 C.14 D.16 D.16

6A806A80DDIf a turn in an inductor is shorted:If a turn in an inductor is shorted: A.There will be an decrease of induction A.There will be an decrease of induction B.There will be a decrease of Q B.There will be a decrease of Q C.There will be overheating with possible burnout C.There will be overheating with possible burnout D.All of the above D.All of the above

6A816A81AAThe relationship between the number of turns and the inductance of a coil may be expressed by:The relationship between the number of turns and the inductance of a coil may be expressed by:

A.The inductance varies approximately as the square of the number of turns A.The inductance varies approximately as the square of the number of turns B.The inductance varies approximately as the square root of the number of turns B.The inductance varies approximately as the square root of the number of turns C.Both A & B C.Both A & B D.None of the above D.None of the above

6A826A82CCThe formula for determining the resonant frequency of a circuit when the inductance and capacitance are The formula for determining the resonant frequency of a circuit when the inductance and capacitance are known is:known is: A.f = 1/(2 pi times the square root of LC) A.f = 1/(2 pi times the square root of LC) B.f = 0.159/(the square root of LC) B.f = 0.159/(the square root of LC) C.Both A & B C.Both A & B D.None of the above D.None of the above

6A836A83DDThe formula for determining the wavelength when the frequency is known is:The formula for determining the wavelength when the frequency is known is: A.Wavelength = 300,000/ f kHz A.Wavelength = 300,000/ f kHz B.Wavelength = 300,000,000/ f Hz B.Wavelength = 300,000,000/ f Hz C.Wavelength = 300/ f MHz C.Wavelength = 300/ f MHz D.All of the above D.All of the above

6A846A84AAThe wavelength of the period of one complete cycle of a radio wave of 0.000,001 second is:The wavelength of the period of one complete cycle of a radio wave of 0.000,001 second is: A.300 M A.300 M B.3000 M B.3000 M C.30 M C.30 M D.70 cm D.70 cm

6A856A85BBThe efficiency of a radio device is:The efficiency of a radio device is: A.The ratio of the power input to the power output A.The ratio of the power input to the power output B.The ratio of the useful power output to the power input B.The ratio of the useful power output to the power input C.The ratio of the minimum power output to the maximum power output C.The ratio of the minimum power output to the maximum power output D.None of the above D.None of the above6A866A86DDWhat is the total impedance of a parallel capacitor and inductor with equal values of reactance?What is the total impedance of a parallel capacitor and inductor with equal values of reactance? A.Infinite total reactance A.Infinite total reactance B.Zero total reactance B.Zero total reactance C.Parallel impedance is resistive and infinite C.Parallel impedance is resistive and infinite D.B & C D.B & C

6A876A87AAThe total inductance of two coils in parallel without any mutual coupling is:The total inductance of two coils in parallel without any mutual coupling is: A.Equal to the product of the two inductances divided by their sum A.Equal to the product of the two inductances divided by their sum B.The sum of the individual inductances B.The sum of the individual inductances

C.Zero C.Zero D.None of the above D.None of the above

6A886A88DDWhat is the total reactance of a series AC circuit, with no resistance and equal inductance and capacitive What is the total reactance of a series AC circuit, with no resistance and equal inductance and capacitive reactances?reactances? A.The two reactances cancel being equal and opposite A.The two reactances cancel being equal and opposite B.Net impedance is purely resistive and contains no reactive component B.Net impedance is purely resistive and contains no reactive component C.The total reactance is zero at the resonant frequency C.The total reactance is zero at the resonant frequency D.All of the above D.All of the above

6A896A89AAThe total inductance of two coils in series without any mutual coupling is:The total inductance of two coils in series without any mutual coupling is: A.The sum of the individual inductances A.The sum of the individual inductances B.The product of the individual inductances divided by their sum B.The product of the individual inductances divided by their sum C.Infinite C.Infinite D.None of the above D.None of the above

6A906A90CCOne wave-length is:One wave-length is: A.The distance a wave will travel in the time for one cycle A.The distance a wave will travel in the time for one cycle B.Centimeter wavelength = 30,000 / frequency MHz B.Centimeter wavelength = 30,000 / frequency MHz C.A and B C.A and B D.Neither A or B D.Neither A or B

6A916A91AAIn an AC circuit, a series inductance acting alone:In an AC circuit, a series inductance acting alone: A.Causes the current to lag the applied voltage by 90 degrees A.Causes the current to lag the applied voltage by 90 degrees B.Causes the current to lead the applied voltage by 90 degrees B.Causes the current to lead the applied voltage by 90 degrees C.Causes the current to lag the applied voltage by 45 degrees C.Causes the current to lag the applied voltage by 45 degrees D.Causes the current to lead the applied voltage by 45 degrees D.Causes the current to lead the applied voltage by 45 degrees

6A926A92DDShock excitation into an L-C circuit is the result of:Shock excitation into an L-C circuit is the result of: A.A voltage being momentarily introduced A.A voltage being momentarily introduced B.The capacitor may be charged B.The capacitor may be charged C.The inductor may have a voltage induced C.The inductor may have a voltage induced D.All of the above D.All of the above

6A936A93AAThe term cathode ray usually applies to:The term cathode ray usually applies to: A.A fairly high velocity electron beam A.A fairly high velocity electron beam B.Background noise B.Background noise C.The logarithm gain of an electron beam C.The logarithm gain of an electron beam

D.None of the above D.None of the above

6A946A94DDShielding an RF inductance:Shielding an RF inductance: A.Increases the losses of the inductance A.Increases the losses of the inductance B.Lowers the inductance value and the Q B.Lowers the inductance value and the Q C.Increases the coil capacity to the shield C.Increases the coil capacity to the shield D.All of the above D.All of the above

6A956A95BBThe tendency of a tank circuit to keep oscillating for a time after the excitation energy has been removed The tendency of a tank circuit to keep oscillating for a time after the excitation energy has been removed is:is: A.Push-pull effect A.Push-pull effect B.Flywheel effect B.Flywheel effect C.Polarizing effect C.Polarizing effect D.Parasitic oscillation D.Parasitic oscillation

6A966A96CCPower factor is defined as:Power factor is defined as: A.The ratio between the resistance and the impedance in a circuit A.The ratio between the resistance and the impedance in a circuit B.The ratio between the true power and the apparent power of a circuit B.The ratio between the true power and the apparent power of a circuit C.Both A&B C.Both A&B D.None of the above D.None of the above

6A976A97BBHigh or low frequency oscillations occurring in circuits other than the original tank desired output High or low frequency oscillations occurring in circuits other than the original tank desired output frequencies are:frequencies are: A.Harmonics A.Harmonics B.Parasitic oscillations B.Parasitic oscillations C.Hysteresis C.Hysteresis D.Eddy currents D.Eddy currents

6A986A98DDWhat are effects of parasitic oscillations?What are effects of parasitic oscillations? A.Change of bias A.Change of bias B.Reduced efficiency of the amplifier tube B.Reduced efficiency of the amplifier tube C.Distortion of the modulated wave C.Distortion of the modulated wave D.All of the above D.All of the above

6A996A99DDThe velocity of propagation of radio frequency waves in free space is:The velocity of propagation of radio frequency waves in free space is: A.300,000 meters / second A.300,000 meters / second B.186,284 miles / second B.186,284 miles / second C.The same as the velocity of light in free space C.The same as the velocity of light in free space

D.All of the above D.All of the above

6A1006A100BBTo double the resonant frequency of a resonant circuit:To double the resonant frequency of a resonant circuit: A.Make C one third of its original value A.Make C one third of its original value B.Make L and C both half their original values B.Make L and C both half their original values C.Decreasing the value of both L and C in any proportion so that their product will be one-half of the C.Decreasing the value of both L and C in any proportion so that their product will be one-half of the original valuesoriginal values D.None of the above D.None of the above

6A1016A101CCHow may the Q of a parallel resonant circuit be increased?How may the Q of a parallel resonant circuit be increased? A.Increasing coupling to the resonant circuit A.Increasing coupling to the resonant circuit B.Using coil and capacitor supports of special low - loss materials B.Using coil and capacitor supports of special low - loss materials C.Both A and B C.Both A and B D.Decreasing coupling to the resonant circuit D.Decreasing coupling to the resonant circuit

6A1026A102CCIf L and C in a parallel resonant circuit resonants at 1000 kHz are so varied that their product remains If L and C in a parallel resonant circuit resonants at 1000 kHz are so varied that their product remains constant, what will be the resulting resonant frequency?constant, what will be the resulting resonant frequency? A.10,000 kHz A.10,000 kHz B.100 kHz B.100 kHz C.1 MHz C.1 MHz D.None of the above D.None of the above

6A1036A103AAWhat is the resonant frequency of a tuned circuit consisting of a 500 picofarad capacitor, a 150 What is the resonant frequency of a tuned circuit consisting of a 500 picofarad capacitor, a 150 microfarad tuning coil, and 10 ohms resistance?microfarad tuning coil, and 10 ohms resistance? A.581 kHz A.581 kHz B.753 kHz B.753 kHz C.498 kHz C.498 kHz D.None of the above D.None of the above

6A1046A104AAWhat is voltage regulation as applied to power supplies?What is voltage regulation as applied to power supplies? A.The ratio of change in voltage between no load and full load to the full-load voltage output A.The ratio of change in voltage between no load and full load to the full-load voltage output B.The ratio of output to input voltage B.The ratio of output to input voltage C.Voltage output of the power supply under full load C.Voltage output of the power supply under full load

D.The ratio of input to output voltage D.The ratio of input to output voltage

6A1056A105DDAn EMF may be generated by sound waves by what principle?An EMF may be generated by sound waves by what principle? A.Electrostatic A.Electrostatic B.Piezo-electric B.Piezo-electric C.Resistance change C.Resistance change D.All of the above D.All of the above

6A1066A106DDHow can you correct power factor in an electrical circuit?How can you correct power factor in an electrical circuit? A.Inductance is used to correct a leading angle A.Inductance is used to correct a leading angle B.Capacitance is used to correct a lagging angle B.Capacitance is used to correct a lagging angle C.Neither A or B C.Neither A or B D.Both A and B D.Both A and B

6A1076A107BBPermeability is:Permeability is: A.The magnetic field created by a conductor wound on a laminated core and carrying any electric current A.The magnetic field created by a conductor wound on a laminated core and carrying any electric current B.The ratio of magnetic flux density in a substance to the magnetizing force which produces it B.The ratio of magnetic flux density in a substance to the magnetizing force which produces it C.Polarized molecular alignment in a ferromagnetic material while under the influence of a magnetizing C.Polarized molecular alignment in a ferromagnetic material while under the influence of a magnetizing forceforce D.Both A and C D.Both A and C

6A1086A108CCThe time in seconds for a capacitor to attain 63.2 % of the applied voltage across its terminals is:The time in seconds for a capacitor to attain 63.2 % of the applied voltage across its terminals is: A.Twice the natural period of oscillation of the circuit A.Twice the natural period of oscillation of the circuit B.Varactance B.Varactance C.Time constant C.Time constant D.Equal to the ohmic resistance of the circuit D.Equal to the ohmic resistance of the circuit6A1096A109BBWhat is the reactance of a 2-henry choke at 3000 Hz?What is the reactance of a 2-henry choke at 3000 Hz? A.5300 ohms A.5300 ohms B.37,680 ohms B.37,680 ohms C.376,800 ohms C.376,800 ohms D.53,000 ohms D.53,000 ohms

6A1106A110BBIf there is no resistance in either leg of a circuit with an inductance of 5 henrys in parallel with a If there is no resistance in either leg of a circuit with an inductance of 5 henrys in parallel with a capacitance of 1 microfarad, what is the equivalent impedance of the parallel network circuit?capacitance of 1 microfarad, what is the equivalent impedance of the parallel network circuit? A.Zero A.Zero B.Infinite B.Infinite C.Median C.Median D.None of the above D.None of the above

6A1116A111CCWhat is the total impedance of a series AC circuit having a resistance of 6 ohms, an inductive reactance What is the total impedance of a series AC circuit having a resistance of 6 ohms, an inductive reactance of 17 ohms, and zero capacitive reactance?of 17 ohms, and zero capacitive reactance? A.15 ohms A.15 ohms B.27 ohms B.27 ohms C.18 ohms C.18 ohms D.5 ohms D.5 ohms

6A1126A112BBThe total impedance of a series AC circuit with an inductive reactance of 24 ohms, a resistance of 16 The total impedance of a series AC circuit with an inductive reactance of 24 ohms, a resistance of 16 ohms, and a capacitive reactance of 16 ohms is:ohms, and a capacitive reactance of 16 ohms is: A.20 ohms A.20 ohms B.16 ohms B.16 ohms C.10 ohms C.10 ohms D.None of the above D.None of the above

6A1136A113DDEssentials for making a good solder connection are:Essentials for making a good solder connection are: A.Bright, clean parts A.Bright, clean parts B.Plenty of heat with the minimum amount of solder used B.Plenty of heat with the minimum amount of solder used C.Discontinue operating on high power C.Discontinue operating on high power D.None of the above D.None of the above

6A1146A114AAFor protection of personnel handling a transmitter:For protection of personnel handling a transmitter: A.Ground all exposed metal parts A.Ground all exposed metal parts B.Transmitter is equipped to shunt grounded faults B.Transmitter is equipped to shunt grounded faults C.Discontinue operating on high power C.Discontinue operating on high power D.None of the above D.None of the above

6A1156A115CCThe ratio of peak-to-effective voltage values of a sign wave are:The ratio of peak-to-effective voltage values of a sign wave are: A.1.414 to 1 A.1.414 to 1 B.1 to 0.707 B.1 to 0.707 C.Both A and B C.Both A and B D.Neither A or B D.Neither A or B

6A1166A116

AAThe opposition to the creation of magnetic lines of force in a magnetic circuit is known as:The opposition to the creation of magnetic lines of force in a magnetic circuit is known as: A.Reluctance A.Reluctance B.Hysteresis B.Hysteresis C.Permeability C.Permeability D.Eddy currents D.Eddy currents

6A1176A117BBThe ratio of magnetic flux density to the field strength is known as:The ratio of magnetic flux density to the field strength is known as: A.Residual magnetism A.Residual magnetism B.Permeability B.Permeability C.Reluctance C.Reluctance D.None of the above D.None of the above

6A1186A118BBThe magnetic force which remains in a substance after the original magnetizing force has been removed The magnetic force which remains in a substance after the original magnetizing force has been removed is known as:is known as: A.Reluctance A.Reluctance B.Residual magnetism B.Residual magnetism C.Permeability C.Permeability D.Hysteresis D.Hysteresis

6A1196A119AAThe direction of electron flow through a coil and the manner of winding the turns:The direction of electron flow through a coil and the manner of winding the turns: A.Influence the direction of magnetic line of force generated by an electromagnet A.Influence the direction of magnetic line of force generated by an electromagnet B.Are determined by the left-hand status rule B.Are determined by the left-hand status rule C.Are determined by the diameter of the wire and length C.Are determined by the diameter of the wire and length D.Both A and C D.Both A and C

6A1206A120AAAdding an iron core to an air-core inductance:Adding an iron core to an air-core inductance: A.Increases the inductance A.Increases the inductance B.Decreases the inductance B.Decreases the inductance C.Does not affect the inductance C.Does not affect the inductance D.Causes parasitic oscillations in the inductor D.Causes parasitic oscillations in the inductor

6A1216A121DDElectromagnets are used in:Electromagnets are used in: A.loudspeakers A.loudspeakers B.meters B.meters C.motors C.motors D.All of the above D.All of the above

6A1226A122CC

What will be the effect of a small increase in the number of turns upon the field strength of a single layer What will be the effect of a small increase in the number of turns upon the field strength of a single layer solenoid?solenoid? A.Decrease in field strength if the coil length is increased A.Decrease in field strength if the coil length is increased B.Unchanged if the spacing is reduced to keep the length constant B.Unchanged if the spacing is reduced to keep the length constant C.Both A and B C.Both A and B D.None of the above D.None of the above

6A1236A123CCCan a transformer be used with direct current?Can a transformer be used with direct current? A.In general, no A.In general, no B.If the DC current is periodically interrupted it would be possible to use an original DC voltage source B.If the DC current is periodically interrupted it would be possible to use an original DC voltage source C.Both A and B C.Both A and B D.None of the above D.None of the above

6A1246A124AAA tube containing either a filament or cathode structure, grid, and a plate is a:A tube containing either a filament or cathode structure, grid, and a plate is a: A.Triode A.Triode B.Tetrode B.Tetrode C.Pentode C.Pentode D.Diode D.Diode

6A1256A125BBA tube similar to a triode with the addition of a spirally wound screen grid between the plate and control A tube similar to a triode with the addition of a spirally wound screen grid between the plate and control grid is a:grid is a: A.Diode A.Diode B.Tetrode B.Tetrode C.Pentode C.Pentode D.Triode D.Triode6A1266A126AATheoretical gain of a tube. The ratio of a small change in plate voltage to give a certain small change in Theoretical gain of a tube. The ratio of a small change in plate voltage to give a certain small change in plate current to a change in grid which would cause the same current:plate current to a change in grid which would cause the same current: A.Amplification factor A.Amplification factor B.Power factor B.Power factor C.Maximum inverse plate voltage C.Maximum inverse plate voltage D.None of the above D.None of the above

6A1276A127DDEffectiveness of the grid in causing changes of plate current:Effectiveness of the grid in causing changes of plate current: A.Transconductance A.Transconductance B.Mutual conductance B.Mutual conductance C.Plate resistance C.Plate resistance D.A & B D.A & B

6A1286A128AA

The maximum negative anode voltage with respect to the cathode. It equals the DC voltage at the input The maximum negative anode voltage with respect to the cathode. It equals the DC voltage at the input to the plus the peak AC voltage applied during the nonconducting portion of the cycle of operation of the to the plus the peak AC voltage applied during the nonconducting portion of the cycle of operation of the tube:tube: A.Maximum inverse plate voltage A.Maximum inverse plate voltage B.Mutual conductance B.Mutual conductance C.Both A & B C.Both A & B D.None of the above D.None of the above

6A1296A129AAWhat is the primary purpose of the control grid of the triode?What is the primary purpose of the control grid of the triode? A.To provide a means of obtaining amplification A.To provide a means of obtaining amplification B.To neutralize RF amplifiers B.To neutralize RF amplifiers C.Blocks passage of electrons C.Blocks passage of electrons D.None of the above D.None of the above

6A1306A130CCWhat is the primary purpose of the screen grid of the tetrode?What is the primary purpose of the screen grid of the tetrode? A.Reduces the grid to plate capacitance, making it unnecessary to neutralize RF amplifiers except at very A.Reduces the grid to plate capacitance, making it unnecessary to neutralize RF amplifiers except at very high frequencieshigh frequencies B.Makes the plate current substantially independent of B.Makes the plate current substantially independent of plate voltage, permitting much higher values of plate voltage, permitting much higher values of amplificationamplification C.Both A & B C.Both A & B D.None of the above D.None of the above

6A1316A131AAWhat is the primary purpose of the suppressor grid of a pentode?What is the primary purpose of the suppressor grid of a pentode? A.Is highly negative with respect to the plate and returns secondary emission to the plate, increasing the A.Is highly negative with respect to the plate and returns secondary emission to the plate, increasing the permissible gain and the tube efficiencypermissible gain and the tube efficiency B.Reduces interelectrode capacitance between control grid and plate making plate efficiency about 10% B.Reduces interelectrode capacitance between control grid and plate making plate efficiency about 10% greater than a triodegreater than a triode C.Both A & B C.Both A & B D.Neither of the above D.Neither of the above

6A1326A132AAThoriated tungsten is usually used to make:Thoriated tungsten is usually used to make: A.Filaments A.Filaments B.Heaters B.Heaters C.Cathodes C.Cathodes D.None of the above D.None of the above

6A1336A133

CCIn what types of circuits do beam power vacuum tubes find application?In what types of circuits do beam power vacuum tubes find application? A.As audio amplifier in the output and power stages of circuits having low to moderately high output A.As audio amplifier in the output and power stages of circuits having low to moderately high output ratingsratings B.As an RF power amplifier B.As an RF power amplifier C.Both A & B C.Both A & B D.None of the above D.None of the above

6A1346A134BBWhen free electrons in a conductor acquire sufficient energy to leave the conductor and pass into the When free electrons in a conductor acquire sufficient energy to leave the conductor and pass into the surrounding space, it is expressed as:surrounding space, it is expressed as: A.Secondary emission A.Secondary emission B.Electron emission B.Electron emission C.Primary electron release C.Primary electron release D.None of the above D.None of the above

6A1356A135BBThe emission of electrons from a material due to the impact of high-velocity electrons on its surface is:The emission of electrons from a material due to the impact of high-velocity electrons on its surface is: A.Primary electron emission A.Primary electron emission B.Secondary emission B.Secondary emission C.Mimetic emission C.Mimetic emission D.None of the above D.None of the above

6A1366A136AACharacteristics of a vacuum tube operating as a class A amplifier:Characteristics of a vacuum tube operating as a class A amplifier: A.Low plate circuit efficiency, about 25%; practically no grid driving power; plate current flowing for A.Low plate circuit efficiency, about 25%; practically no grid driving power; plate current flowing for 360 degrees of each cycle; practically no distortion of the output waveshape360 degrees of each cycle; practically no distortion of the output waveshape B.Plate circuit efficiency, about 50-60%; plate current flows slightly more than 180 degrees of each B.Plate circuit efficiency, about 50-60%; plate current flows slightly more than 180 degrees of each cycle, medium power outputcycle, medium power output C.High efficiency, up to 80%; plate current drawn in bursts; great distortion of output waveshape C.High efficiency, up to 80%; plate current drawn in bursts; great distortion of output waveshape D.None of the above D.None of the above

6A1376A137BBCharacteristics of a vacuum tube operating as a class B amplifier:Characteristics of a vacuum tube operating as a class B amplifier: A.Low plate circuit efficiency, about 25%; practically no grid driving power; plate current flowing for A.Low plate circuit efficiency, about 25%; practically no grid driving power; plate current flowing for 360 degrees of each cycle; practically no distortion of the output waveshape360 degrees of each cycle; practically no distortion of the output waveshape B.Plate circuit efficiency, about 50-60%; plate current flows slightly more than 180 degrees of each B.Plate circuit efficiency, about 50-60%; plate current flows slightly more than 180 degrees of each cycle, medium power outputcycle, medium power output C.High efficiency, up to 80%; plate current drawn in bursts; great distortion of output waveshape C.High efficiency, up to 80%; plate current drawn in bursts; great distortion of output waveshape D.None of the above D.None of the above

6A1386A138DDFactors which determine bios voltage of a vacuum tube:Factors which determine bios voltage of a vacuum tube: A.Class of operation, plate supply voltage, permissible distortion A.Class of operation, plate supply voltage, permissible distortion B.Grid signal magnitude, permissible plate dissipation, desired amplification factor B.Grid signal magnitude, permissible plate dissipation, desired amplification factor C.The no-signal plate current desired, the desirability of drawing grid current C.The no-signal plate current desired, the desirability of drawing grid current D.All of the above D.All of the above

6A1396A139AAIn the usual Class A amplifier:In the usual Class A amplifier: A.There is no grid current A.There is no grid current B.Plate current flows slightly more than 180 degrees of each cycle B.Plate current flows slightly more than 180 degrees of each cycle C.Biased to twice C.Biased to twice D.None of the above D.None of the above

6A1406A140AAThe DC bias in a Class A amplifier:The DC bias in a Class A amplifier: A.Usually is negative as measured at the grid with respect to cathode A.Usually is negative as measured at the grid with respect to cathode B.Usually is positive as measured at the grid with respect to cathode B.Usually is positive as measured at the grid with respect to cathode C.Cannot be determined C.Cannot be determined D.None of the above D.None of the above

6A1416A141CCWhat is the effect of incorrect grid bias in a Class A amplifier?What is the effect of incorrect grid bias in a Class A amplifier? A.Distortion of the output waveshape A.Distortion of the output waveshape B.Possible excessive plate dissipation if the bias is too low B.Possible excessive plate dissipation if the bias is too low C.Both A & B C.Both A & B D.None of the above D.None of the above

6A1426A142AAThe approximate efficiency of a Class A vacuum tube amplifier:The approximate efficiency of a Class A vacuum tube amplifier: A.20%-30% A.20%-30% B.60% B.60% C.85% C.85% D.100% D.100%

6A1436A143BBThe approximate efficiency of a Class B vacuum tube amplifier:The approximate efficiency of a Class B vacuum tube amplifier: A.20%-30% A.20%-30% B.60% B.60%

C.85% C.85% D.100% D.100%

6A1446A144CCThe approximate efficiency of a Class C vacuum tube amplifier:The approximate efficiency of a Class C vacuum tube amplifier: A.20%-30% A.20%-30% B.60% B.60% C.85% C.85% D.100% D.100%

6A1456A145BBA charge due to the accumulation of negative electrons because the plate potential cannot attract all of theA charge due to the accumulation of negative electrons because the plate potential cannot attract all of the electrons leaving the emitter:electrons leaving the emitter: A.Getter A.Getter B.Space charge B.Space charge C.Plate saturation C.Plate saturation D.None of the above D.None of the above

6A1466A146BBA material flashed by the application of heat after the tube is evacuated that absorbs any gases remaining A material flashed by the application of heat after the tube is evacuated that absorbs any gases remaining inside the tube:inside the tube: A.Space charge A.Space charge B.Getter B.Getter C.Collector C.Collector D.Emitter D.Emitter6A1476A147BBWhat types of vacuum tube filaments are reactivated:What types of vacuum tube filaments are reactivated: A.Barium berylliate A.Barium berylliate B.Thoriated tungsten B.Thoriated tungsten C.Nickel C.Nickel D.Thorium oxide D.Thorium oxide

6A1486A148AAA tungsten filament is operated at ____ temperature than a thoriated tungsten filament:A tungsten filament is operated at ____ temperature than a thoriated tungsten filament: A.A higher A.A higher B.A lower B.A lower C.The same C.The same D.Unknown D.Unknown

6A1496A149AAThe presence of gas within a tube is indicated:The presence of gas within a tube is indicated: A.By a blue glow A.By a blue glow B.By a red glow B.By a red glow C.By a yellow glow C.By a yellow glow

D.None of the above D.None of the above

6A1506A150CCThe cathode of an indirectly heated type of vacuum tube should be maintained at nearly the same The cathode of an indirectly heated type of vacuum tube should be maintained at nearly the same potential as the heater circuit:potential as the heater circuit: A.To reduce hum pickup into the cathode A.To reduce hum pickup into the cathode B.To prevent breakdown of the insulation between the heater and cathode B.To prevent breakdown of the insulation between the heater and cathode C.A & B C.A & B D.None of the above D.None of the above

6A1516A151DDTransmitting tube filaments should be maintained at recommended voltages:Transmitting tube filaments should be maintained at recommended voltages: A.To realize the greatest life-expectancy A.To realize the greatest life-expectancy B.If the filament voltage is too low, the emission will be reduced and operation of the circuit may be B.If the filament voltage is too low, the emission will be reduced and operation of the circuit may be adversely affectedadversely affected C.If the voltage is too high, the filament may burn out C.If the voltage is too high, the filament may burn out D.All of the above D.All of the above

6A1526A152AAUse of an AC filament supply is desirable:Use of an AC filament supply is desirable: A.Mostly for practical reasons. It is easily obtainable A.Mostly for practical reasons. It is easily obtainable B.Hum may be introduced into the amplifier B.Hum may be introduced into the amplifier C.A & B C.A & B D.None of the above D.None of the above6A1536A153AAIf a DC filament supply is used, it is advisable to periodically reverse the polarity of the filament If a DC filament supply is used, it is advisable to periodically reverse the polarity of the filament potential:potential: A.To lengthen the life of the filament A.To lengthen the life of the filament B.To lengthen the life of the power source B.To lengthen the life of the power source C.Both A & B C.Both A & B D.None of the above D.None of the above

6A1546A154DDBias voltage on the grid of an AF amplifier tube:Bias voltage on the grid of an AF amplifier tube: A.Determines the operating conditions of the tube A.Determines the operating conditions of the tube B.The correct value is essential for undistorted Class A output B.The correct value is essential for undistorted Class A output C.In power amplifiers the plate current must be limited to safe value not to exceed the rated plate C.In power amplifiers the plate current must be limited to safe value not to exceed the rated plate dissipation of the tubedissipation of the tube D.All of the above D.All of the above

6A1556A155CCThe screen grid in a vacuum tube:The screen grid in a vacuum tube: A.Makes it unnecessary to neutralize RF amplifiers except at very high frequencies, A.Makes it unnecessary to neutralize RF amplifiers except at very high frequencies, B.Makes it possible to obtain much higher values of amplification than with triodes B.Makes it possible to obtain much higher values of amplification than with triodes

C.A & B C.A & B D.None of the above D.None of the above

6A1566A156DDThe suppressor grid in a multielement vacuum tube:The suppressor grid in a multielement vacuum tube: A.Is highly negative with respect to the plate A.Is highly negative with respect to the plate B.Returns secondary electrons to the plate B.Returns secondary electrons to the plate C.Increases the permissible gain and the efficiency of the tube C.Increases the permissible gain and the efficiency of the tube D.All of the above D.All of the above

6A1576A157DDThe gain of a triode audio amplifier is a function of:The gain of a triode audio amplifier is a function of: A.Tube transconduction A.Tube transconduction B.Plate load impedance B.Plate load impedance C.Transformer step-up (if used) C.Transformer step-up (if used) D.All of the above D.All of the above

6A1586A158CC"Load" on a vacuum tube commonly refers to:"Load" on a vacuum tube commonly refers to: A.The impedance through which plate current flows to produce a useful output A.The impedance through which plate current flows to produce a useful output B.Increases as the load impedance approaches the internal plate impedance in value B.Increases as the load impedance approaches the internal plate impedance in value C.A & B C.A & B D.None of the above D.None of the above

6A1596A159AAA case in which the grid is held at an excessively negative value for a period of time thereby cutting off A case in which the grid is held at an excessively negative value for a period of time thereby cutting off plate current:plate current: A.Blocked grid A.Blocked grid B.Blocked plate B.Blocked plate C.Motorboating C.Motorboating D.Tuned grid D.Tuned grid

6A1606A160AAThe maximum power that can be safely and continuously dissipated in heat on the plate:The maximum power that can be safely and continuously dissipated in heat on the plate: A.Maximum plate dissipation A.Maximum plate dissipation B.Maximum power dissipation B.Maximum power dissipation C.Continuous plate dissipation C.Continuous plate dissipation D.Plate heat dissipation D.Plate heat dissipation

6A1616A161AAOccurs when plate current equals electron emission for any given filament or cathode temperature:Occurs when plate current equals electron emission for any given filament or cathode temperature: A.Plate saturation A.Plate saturation B.Electron saturation B.Electron saturation C.Filament saturation C.Filament saturation

D.None of the above D.None of the above

6A1626A162BBThe most desirable factor in the choice of a vacuum tube for a voltage amplifier:The most desirable factor in the choice of a vacuum tube for a voltage amplifier: A.A low value of transconductance A.A low value of transconductance B.A high value of transconductance B.A high value of transconductance C.High output tube capacitance C.High output tube capacitance D.None of the above D.None of the above

6A1636A163AALack of requirement for neutralizing, except at ultra high frequencies, is an advantage of a tetrode over Lack of requirement for neutralizing, except at ultra high frequencies, is an advantage of a tetrode over ____:____: A.A Triode A.A Triode B.A Pentode B.A Pentode C.A & B C.A & B D.None of the above D.None of the above

6A1646A164CCCharacteristics of a vacuum tube operating as a Class C amplifier:Characteristics of a vacuum tube operating as a Class C amplifier: A.Low plate circuit efficiency, about 25%; practically no grid driving power; plate current flowing for A.Low plate circuit efficiency, about 25%; practically no grid driving power; plate current flowing for 360 degrees of each cycle; practically no distortion of the output waveshape360 degrees of each cycle; practically no distortion of the output waveshape B.Plate circuit efficiency, about 50-60%; plate current flows slightly more than 180 degrees of each B.Plate circuit efficiency, about 50-60%; plate current flows slightly more than 180 degrees of each cycle; medium power outputcycle; medium power outputC.High plate circuit efficiency, up to 80%; plate current drawn in bursts; great distortion of output C.High plate circuit efficiency, up to 80%; plate current drawn in bursts; great distortion of output waveshapewaveshape D.None of the above D.None of the above

6A1656A165CCPlate current flows for less than 180 degrees (about 120 degrees when the grid bias is about twice cutoff Plate current flows for less than 180 degrees (about 120 degrees when the grid bias is about twice cutoff value) in what class amplifier?value) in what class amplifier? A.A A.A B.B B.B C.C C.C D.AB D.AB

6A1666A166AATubes operated as Class C amplifiers are not suited for audio-frequency amplifiers:Tubes operated as Class C amplifiers are not suited for audio-frequency amplifiers: A.Because of excessive distortion A.Because of excessive distortion

B.Because of current requirement B.Because of current requirement C.Because of reduced life expectancy of the filament C.Because of reduced life expectancy of the filament D.None of the above D.None of the above

6A1676A167DDLow plate current may be caused by:Low plate current may be caused by: A.Low filament emission and voltage A.Low filament emission and voltage B.Excessive bias value, shorted screen by-pass capacitor B.Excessive bias value, shorted screen by-pass capacitor C.Open grid circuit, low screen grid supply voltage C.Open grid circuit, low screen grid supply voltage D.All of the above D.All of the above

6A1686A168AAA tuned circuit made up of inductance and capacitance is:A tuned circuit made up of inductance and capacitance is: A.An oscillator A.An oscillator B.A neutralizer B.A neutralizer C.Voltage divider C.Voltage divider D.None of the above D.None of the above

6A1696A169BBSome radio-frequency amplifiers must be neutralized:Some radio-frequency amplifiers must be neutralized: A.To maintain linear operation A.To maintain linear operation B.To prevent sustained oscillations from occurring in the amplifier B.To prevent sustained oscillations from occurring in the amplifier C.Sustain feedback C.Sustain feedback D.None of the above D.None of the above

6A1706A170DDCavity resonators are:Cavity resonators are: A.A form of resonant tank circuit A.A form of resonant tank circuit B.Consist of a hollow metal cylinder bead on all sides B.Consist of a hollow metal cylinder bead on all sides C.Have a very high Q and selectivity C.Have a very high Q and selectivity D.All of the above D.All of the above

6A1716A171DDThe diode detector:The diode detector: A.Is square law on weak signals A.Is square law on weak signals B.Is practically linear on strong signals B.Is practically linear on strong signals C.Is square law on strong signals C.Is square law on strong signals D.A & B D.A & B

6A1726A172

DDThe functioning of a grid-leak detector:The functioning of a grid-leak detector: A.Depends on the ability of the grid leak and capacitor to follow the average grid current variations A.Depends on the ability of the grid leak and capacitor to follow the average grid current variations which are directly proportioned to the modulation envelopewhich are directly proportioned to the modulation envelope B.Depends on second harmonic distortion B.Depends on second harmonic distortion C.Very sensitive to weak signals C.Very sensitive to weak signals D.A & C D.A & C

6A1736A173DDCharacteristic of a square law type of vacuum tube detector:Characteristic of a square law type of vacuum tube detector: A.High sensitivity is provided due to the audio output signal amplitude being proportioned to the square A.High sensitivity is provided due to the audio output signal amplitude being proportioned to the square of the radio frequency voltageof the radio frequency voltage B.High percentage of second harmonic distortion B.High percentage of second harmonic distortion C.Works on weak signals only C.Works on weak signals only D.All of the above D.All of the above

6A1746A174AAA diode detector ordinarily produces ____ overall distortion of the audio output wave than does a triode A diode detector ordinarily produces ____ overall distortion of the audio output wave than does a triode detector:detector: A.Lower A.Lower B.Higher B.Higher C.Practically the same C.Practically the same D.Either A or B D.Either A or B

6A1756A175DDOperating conditions for determining that a tube is being used as a power detector:Operating conditions for determining that a tube is being used as a power detector: A.Bias at about cutoff A.Bias at about cutoff B.High input grid resistance B.High input grid resistance C.Plate circuit rectification C.Plate circuit rectification D.All of the above D.All of the above

6A1766A176AAWhy is a center top usually provided for vacuum tube plate and grid return circuits when and AC Why is a center top usually provided for vacuum tube plate and grid return circuits when and AC filament supply is used?filament supply is used? A.To prevent hum voltage from modulating the normal signals A.To prevent hum voltage from modulating the normal signals B.To allow more filament current B.To allow more filament current C.A & B C.A & B D.None of the above D.None of the above

6A1776A177DDHow would you determine the cathode-bias resistance necessary to provide correct grid bias for an How would you determine the cathode-bias resistance necessary to provide correct grid bias for an amplifier?amplifier? A.Bias equals the IR drop across the cathode A.Bias equals the IR drop across the cathode B.Bias is found by dividing the desired DC bias voltage by the total no-signal cathode current B.Bias is found by dividing the desired DC bias voltage by the total no-signal cathode current C.For a tetrode or pentode, the screen current must be added to the plate current C.For a tetrode or pentode, the screen current must be added to the plate current D.All of the above D.All of the above

6A1786A178AAGiven the following vacuum tube constants: Gp = 1000 V, Ip = 150 mA, Ig = 10 mA, Grid leaks = 5000Given the following vacuum tube constants: Gp = 1000 V, Ip = 150 mA, Ig = 10 mA, Grid leaks = 5000 ohms. What would be the grid bias voltage?ohms. What would be the grid bias voltage? A.50 V A.50 V B.100 V B.100 V C.25 V C.25 V D.None of the above D.None of the above

6A1796A179CCWhat currents will be indicated by a milliammeter connected between the center top of the filament What currents will be indicated by a milliammeter connected between the center top of the filament transformer of a tetrode and negative high voltage?transformer of a tetrode and negative high voltage? A.Plate current A.Plate current B.Screen grid current B.Screen grid current C.Combined plate and screen grid currents C.Combined plate and screen grid currents D.None of the above D.None of the above

6A1806A180AAA dynatron oscillator is a ____ which depends upon the negative resistance characteristic of a tetrode A dynatron oscillator is a ____ which depends upon the negative resistance characteristic of a tetrode tube for its operation:tube for its operation: A.Tuned circuit operation A.Tuned circuit operation B.Diode detector B.Diode detector C.Magnetron oscillator C.Magnetron oscillator D.Meystron oscillator D.Meystron oscillator

6A1816A181DDMaterials which can be used as crystal detectors:Materials which can be used as crystal detectors: A.Silicon, galena A.Silicon, galena B.Carborundum, iron pyrites B.Carborundum, iron pyrites C.Silicon, iron pyrites C.Silicon, iron pyrites D.All of the above D.All of the above

6A1826A182

CCA power detector may be operated:A power detector may be operated: A.As a square law detector A.As a square law detector B.As a linear detector B.As a linear detector C.As either a square law detector or a linear detector C.As either a square law detector or a linear detector D.None of the above D.None of the above

6A1836A183AAUsed to multiply the fundamental frequency by two:Used to multiply the fundamental frequency by two: A.Frequency doubler A.Frequency doubler B.Harmonic generator with a suitable resonant circuit B.Harmonic generator with a suitable resonant circuit C.A & B C.A & B D.None of the above D.None of the above

6A1846A184DDWhen used as an RF amplifier, a pentode vacuum tube:When used as an RF amplifier, a pentode vacuum tube: A.Usually does not require neutralization A.Usually does not require neutralization B.Usually requires neutralization B.Usually requires neutralization C.May require neutralization at ultra-high frequencies C.May require neutralization at ultra-high frequencies D.A & C D.A & C

6A1856A185CCA quartz crystal in a radio transmitter:A quartz crystal in a radio transmitter: A.Is used to provide a high degree of master-oscillator frequency stability A.Is used to provide a high degree of master-oscillator frequency stability B.May be the sole tuned circuit in the oscillator B.May be the sole tuned circuit in the oscillator C.A & B C.A & B D.None of the above D.None of the above

6A1866A186DDAdvantage of crystal control over tuned circuit oscillators:Advantage of crystal control over tuned circuit oscillators: A.Very high Q A.Very high Q B.Compact size B.Compact size C.Excellent frequency stability C.Excellent frequency stability D.All of the above D.All of the above

6A1876A187BBIf the crystal will undergo very small changes in its operating frequency with relatively large temperature If the crystal will undergo very small changes in its operating frequency with relatively large temperature variations:variations: A.A high-temperature coefficient crystal A.A high-temperature coefficient crystal B.A low-temperature coefficient crystal B.A low-temperature coefficient crystal C.A constant-temperature coefficient crystal C.A constant-temperature coefficient crystal D.None of the above D.None of the above

6A1886A188AA

A separate source of power is sometimes desirable for crystal-oscillator units in a transmitter:A separate source of power is sometimes desirable for crystal-oscillator units in a transmitter: A.To prevent dynamic instability of the crystal oscillator A.To prevent dynamic instability of the crystal oscillator B.To prevent thermocoupling of the crystal oscillator B.To prevent thermocoupling of the crystal oscillator C.To prevent overtuning of the crystal oscillator C.To prevent overtuning of the crystal oscillator D.To cause dynamic instability of the crystal oscillator D.To cause dynamic instability of the crystal oscillator

6A1896A189DD"The temperature coefficient of an x-cut crystal is negative":"The temperature coefficient of an x-cut crystal is negative": A.The operating frequency of the crystal will decrease as the temperature decreases A.The operating frequency of the crystal will decrease as the temperature decreases B.The operating frequency of the crystal will decrease as the temperature increases B.The operating frequency of the crystal will decrease as the temperature increases C.The operating frequency of the crystal will increase as the temperature decreases C.The operating frequency of the crystal will increase as the temperature decreases D.B & C D.B & C

6A1906A190CCIf you apply DC voltage to the opposite plane surfaces of a quartz crystal:If you apply DC voltage to the opposite plane surfaces of a quartz crystal: A.The crystal plate will always undergo a physical distortion A.The crystal plate will always undergo a physical distortion B.The crystal might crack under the strain of displacement caused by too much voltage B.The crystal might crack under the strain of displacement caused by too much voltage C.A & B C.A & B D.None of the above D.None of the above

6A1916A191DD"The temperature coefficient of a y-cut crystal is positive" means:"The temperature coefficient of a y-cut crystal is positive" means: A.The operating frequency of the crystal will decrease as the temperature decreases A.The operating frequency of the crystal will decrease as the temperature decreases B.The operating frequency of the crystal will increase as the temperature increases B.The operating frequency of the crystal will increase as the temperature increases C.The operating frequency of the crystal will decrease as the temperature increases C.The operating frequency of the crystal will decrease as the temperature increases D.A & B D.A & B

6A1926A192BBTwo dissimilar metals joined together and producing a current between them when the junction is heated Two dissimilar metals joined together and producing a current between them when the junction is heated is:is: A.A point contact type transistor A.A point contact type transistor B.A thermocouple B.A thermocouple C.A junction contact type transistor C.A junction contact type transistor D.A solenoid D.A solenoid

6A1936A193DDWaveguides:Waveguides: A.A type of transmission line A.A type of transmission line B.Hollow rectangular or circular pipe B.Hollow rectangular or circular pipe C.Fine application as transmission lines C.Fine application as transmission lines D.All of the above D.All of the above

6A1946A194DDTransistors may be compared to a conventional triode vacuum tube functionally:Transistors may be compared to a conventional triode vacuum tube functionally:

A.Emitter corresponds to the cathode A.Emitter corresponds to the cathode B.Collector corresponds to the plate B.Collector corresponds to the plate C.Base corresponds to the grid C.Base corresponds to the grid D.All of the above D.All of the above

6A1956A195CCTypes of transistors:Types of transistors: A.Point-contact A.Point-contact B.Junction B.Junction C.Both A & B C.Both A & B D.NPP D.NPP

6A1966A196DDWhen using and storing crystal microphones:When using and storing crystal microphones: A.They should be protected from shock and vibration A.They should be protected from shock and vibration B.They should be protected from humidity B.They should be protected from humidity C.They should be protected from high temperatures C.They should be protected from high temperatures D.All of the above D.All of the above

6A1976A197AAWhat effect does a change in the dielectric constant of a capacitor dielectric material have upon the What effect does a change in the dielectric constant of a capacitor dielectric material have upon the capacitance of a capacitor:capacitance of a capacitor: A.Capacity varies directly with the dielectric constant A.Capacity varies directly with the dielectric constant B.Capacity may fluctuate wildly B.Capacity may fluctuate wildly C.There is no effect upon the capacitance C.There is no effect upon the capacitance D.None of the above D.None of the above

6A1986A198AAIncreasing the number of plates of a capacitor:Increasing the number of plates of a capacitor: A.Will increase the capacitance A.Will increase the capacitance B.Will decrease the capacitance B.Will decrease the capacitance C.Will have no effect on the capacitance C.Will have no effect on the capacitance D.Will make the capacitance fluctuate D.Will make the capacitance fluctuate

6A1996A199AAIf the dielectric constants of a capacitor dielectric material between the capacitor plates were changed If the dielectric constants of a capacitor dielectric material between the capacitor plates were changed from 1 to 1:from 1 to 1: A.The capacitance would be twice its original value A.The capacitance would be twice its original value B.The capacitance would be half its original value B.The capacitance would be half its original value C.The capacitance would decay rapidly C.The capacitance would decay rapidly D.None of the above D.None of the above

6A2006A200DD

Contacts which slide together on opening and closing:Contacts which slide together on opening and closing: A.Are butt joined A.Are butt joined B.Are known as self-wiping B.Are known as self-wiping C.Keep the contacts clean by their action C.Keep the contacts clean by their action D.B & C D.B & C

6A2016A201DDPermanent magnets used in head telephones:Permanent magnets used in head telephones: A.Place the diaphragms under tension so that the sensitivity of the telephones will be increased A.Place the diaphragms under tension so that the sensitivity of the telephones will be increased B.Improve the frequency response B.Improve the frequency response C.Prevents production of second harmonics in the telephones C.Prevents production of second harmonics in the telephones D.All of the above D.All of the above

6A2026A202AAEmergency repairs to an inductance coil having burned or charred insulation:Emergency repairs to an inductance coil having burned or charred insulation: A.Are generally impractical, short of rewinding the coil with good wire A.Are generally impractical, short of rewinding the coil with good wire B.Are always practical if repaired by coating the bad turns with insulating varnish B.Are always practical if repaired by coating the bad turns with insulating varnish C.A & B C.A & B D.None of the above D.None of the above

6A2036A203DDIndications of a defective vacuum tube in a transmitter:Indications of a defective vacuum tube in a transmitter: A.Gas blow within the tube, excessive plate color due to overheating A.Gas blow within the tube, excessive plate color due to overheating B.No light from the filament, insufficient plate current, reduced output B.No light from the filament, insufficient plate current, reduced output C.Excessive plate current, possible internal arcing, fluctuating plate or grid current C.Excessive plate current, possible internal arcing, fluctuating plate or grid current D.All of the above D.All of the above

6A2046A204CCThe breakdown voltage rating of a capacitor are determined by:The breakdown voltage rating of a capacitor are determined by: A.The type of dielectric material used A.The type of dielectric material used B.The thickness of the dielectric material B.The thickness of the dielectric material C.A & B C.A & B D.None of the above D.None of the above

6A2056A205DDCrystal surfaces should be free of dirt of grease to operate properly:Crystal surfaces should be free of dirt of grease to operate properly: A.Do not touch the faces of the crystal with the fingers A.Do not touch the faces of the crystal with the fingers B.Clean the faces with soap and water B.Clean the faces with soap and water C.Clean the faces with carbon tetrachloride C.Clean the faces with carbon tetrachloride

D.All of the above D.All of the above

6A2066A206DDA purplish glow from within a tube indicates:A purplish glow from within a tube indicates: A.A soft tube A.A soft tube B.A hard tube B.A hard tube C.Air or undesired gases within the tube C.Air or undesired gases within the tube D.A & C D.A & C

6A2076A207AAGiven a solenoid with a resistance of 5 ohms and 0.34 through the winding when 1108 at 60 Hz is Given a solenoid with a resistance of 5 ohms and 0.34 through the winding when 1108 at 60 Hz is applied. What is the impedance?applied. What is the impedance? A.367 ohms A.367 ohms B.350 ohms B.350 ohms C.360 ohms C.360 ohms D.None of the above D.None of the above

6A2086A208DDUse of a low pass filter network:Use of a low pass filter network: A.Ripple filter in power supplies, harmonic suppression filters in antenna systems A.Ripple filter in power supplies, harmonic suppression filters in antenna systems B.Line noise filters, tone control systems B.Line noise filters, tone control systems C.Crossover networks, output filters of detector circuits C.Crossover networks, output filters of detector circuits D.All of the above D.All of the above

6A2096A209BBA special type of power supply filter choke whose inductance is inversely proportioned to values of DC A special type of power supply filter choke whose inductance is inversely proportioned to values of DC within specified limits is:within specified limits is: A.Smoothing choke A.Smoothing choke B.Swinging choke B.Swinging choke C.Radio frequency choke C.Radio frequency choke D.Audio frequency choke D.Audio frequency choke

6A2106A210AAThe best suited material for use as an antenna strain insulator exposed to the elements:The best suited material for use as an antenna strain insulator exposed to the elements: A.Glazed porcelain A.Glazed porcelain B.Glass B.Glass C.Graphite composite C.Graphite composite D.Rubber D.Rubber

6A2116A211DDMaterials frequently used for relay contacts:Materials frequently used for relay contacts: A.Tungsten A.Tungsten B.Silver B.Silver C.Gold C.Gold

D.All of the above D.All of the above

6A2126A212DDWhy is rosin used as a soldering flux?Why is rosin used as a soldering flux? A.It is noncorrosive A.It is noncorrosive B.It allows a perfect soldering bond to be made B.It allows a perfect soldering bond to be made C.It possesses good insulation qualities C.It possesses good insulation qualities D.All of the above D.All of the above

6A2136A213AAWhat substance is the most widely used in crystal oscillators?What substance is the most widely used in crystal oscillators? A.Quartz A.Quartz B.Galena B.Galena C.Silicon C.Silicon D.Tourmaline D.Tourmaline

6A2146A214BBWhy is an oscillator crystal operated at a constant temperature?Why is an oscillator crystal operated at a constant temperature? A.Just because, stupid! A.Just because, stupid! B.To maintain a constant frequency output from the oscillator B.To maintain a constant frequency output from the oscillator C.Constant temperature allows easier frequency change C.Constant temperature allows easier frequency change D.None of the above D.None of the above

6A2156A215DDThe advantage of a single-button carbon microphone:The advantage of a single-button carbon microphone: A.High output voltage A.High output voltage B.Sensitivity B.Sensitivity C.Low cost C.Low cost D.All of the above D.All of the above

6A2166A216DDA carbon microphone should not be:A carbon microphone should not be: A.Jarred while in operation A.Jarred while in operation B.Tapped while in operation B.Tapped while in operation C.Subjected to violent sound intensities C.Subjected to violent sound intensities D.All of the above D.All of the above

6A2176A217AAIn connecting head telephones directly in the plate circuit of a vacuum tube one should observe the In connecting head telephones directly in the plate circuit of a vacuum tube one should observe the proper polarity:proper polarity: A.To maintain maximum sensitivity in the headphones A.To maintain maximum sensitivity in the headphones B.So its current flows opposed to the field strength of the permanent magnet B.So its current flows opposed to the field strength of the permanent magnet C.A & B C.A & B D.None of the above D.None of the above

6A2186A218AAWhat should the plate current do in the operation of a Class B audio amplifier?What should the plate current do in the operation of a Class B audio amplifier? A.Fluctuate A.Fluctuate B.Remain Steady B.Remain Steady C.Increase C.Increase D.None of the above D.None of the above

6A2196A219AAWhat turns ratio does a transformer need to match a source impedance of 500 ohms to a load of 10 ohms?What turns ratio does a transformer need to match a source impedance of 500 ohms to a load of 10 ohms? A.7.1 to 1 A.7.1 to 1 B.7 to 1 B.7 to 1 C.14 to 1 C.14 to 1 D.None of the above D.None of the above

6A2206A220CCWhat microphones have a high impedance output?What microphones have a high impedance output? A.Crystal A.Crystal B.Dynamic B.Dynamic C.Any C.Any D.None of the above D.None of the above

6A2216A221CCHow may low impedance (75 ohm) head telephones be connected to the output of a vacuum tube?How may low impedance (75 ohm) head telephones be connected to the output of a vacuum tube? A.By using an impedance matching transformer in the output stage A.By using an impedance matching transformer in the output stage B.Connect them as a cathode bias resistor in the output stage B.Connect them as a cathode bias resistor in the output stage C.Either A or B C.Either A or B D.None of the above D.None of the above

6A2226A222CCWhy do headphones usually have high-impedance windings?Why do headphones usually have high-impedance windings? A.They can usually be operated without an impedance matching transformer A.They can usually be operated without an impedance matching transformer B.They represent a closer match to the plate load impedance for the tube delivering necessary driving B.They represent a closer match to the plate load impedance for the tube delivering necessary driving power than low impedance planespower than low impedance planes C.A & B C.A & B D.None of the above D.None of the above

6A2236A223DDA "choke" coil:A "choke" coil: A.Offers a relatively high impedance to AC currents A.Offers a relatively high impedance to AC currents B.Has a high "Q" (low RF losses) B.Has a high "Q" (low RF losses) C.Offers a low resistance to DC currents C.Offers a low resistance to DC currents D.All of the above D.All of the above

6A2246A224DDWhy is correct grid bias necessary for audio frequency amplifier?Why is correct grid bias necessary for audio frequency amplifier? A.To minimize distortion A.To minimize distortion B.To set the operating conditions for determining the class of amplifications B.To set the operating conditions for determining the class of amplifications C.So as not to exceed the rated plate dissipation of the tube C.So as not to exceed the rated plate dissipation of the tube D.All of the above D.All of the above

6A2256A225AAWhen a tube is used as a Class B amplifier what portion of the excitation voltage cycle does plate current When a tube is used as a Class B amplifier what portion of the excitation voltage cycle does plate current flow?flow? A.Slightly more than 180 degrees A.Slightly more than 180 degrees B.Slightly less than 180 degrees B.Slightly less than 180 degrees C.360 degrees C.360 degrees D.None of the above D.None of the above

6A2266A226AAA properly operated Class A audio amplifier:A properly operated Class A audio amplifier: A.Produces no serious modification of the input waveform A.Produces no serious modification of the input waveform B.Serious distortion is present B.Serious distortion is present C.A & B C.A & B D.All of the above D.All of the above

6A2276A227DDWhat is the main advantage obtained by using two triodes in push-pull in a Class a audio frequency What is the main advantage obtained by using two triodes in push-pull in a Class a audio frequency amplifier?amplifier? A.Increased power output A.Increased power output B.Cancellation of even harmonic distortion in the output B.Cancellation of even harmonic distortion in the output C.Elimination of DC saturation, elimination of cathode by-pass capacitor C.Elimination of DC saturation, elimination of cathode by-pass capacitor D.All of the above D.All of the above

6A2286A228AAWhat is the maximum permissible RMS value of audio voltage which can be applied to the grid of a What is the maximum permissible RMS value of audio voltage which can be applied to the grid of a Class A audio amplifier which has a grid bias of 10 V?Class A audio amplifier which has a grid bias of 10 V? A.7.07 V A.7.07 V B.8 V B.8 V C.10 V C.10 V D.14.14 V D.14.14 V

6A2296A229DDDistortion in a Class A amplifier can be caused by:Distortion in a Class A amplifier can be caused by: A.Insufficient plate and screen potentials, incorrect grid bias defective rube A.Insufficient plate and screen potentials, incorrect grid bias defective rube B.Leaky or shorted input coupling capacitor B.Leaky or shorted input coupling capacitor

C.Excessive anokutyde if grid signal, incorrect value of load impedance C.Excessive anokutyde if grid signal, incorrect value of load impedance D.All of the above D.All of the above

6A2306A230DDVacuum tubes operating as Class A amplifiers may be used as:Vacuum tubes operating as Class A amplifiers may be used as: A.Audio power amplifiers, audio voltage amplifiers, microphones amplifiers, line amplifiers A.Audio power amplifiers, audio voltage amplifiers, microphones amplifiers, line amplifiers B.Oscilloscope amplifiers, modulators B.Oscilloscope amplifiers, modulators C.Phonograph amplifiers C.Phonograph amplifiers D.All of the above D.All of the above

A6231A6231AAWhy is a push-pull audio frequency amplifier preferable to a single-tube stage?Why is a push-pull audio frequency amplifier preferable to a single-tube stage? A.When compared with a single-tube stage, power output is doubled A.When compared with a single-tube stage, power output is doubled B.When compared with a single-tube stage, power output is the same B.When compared with a single-tube stage, power output is the same C.When compared with a single-tube stage, power output is cut in half C.When compared with a single-tube stage, power output is cut in half D.None of the above D.None of the above

6A2326A232AAWhat is the DC plate voltage of a resistance-coupled amplifier state with a plate-supply voltage of 260 V,What is the DC plate voltage of a resistance-coupled amplifier state with a plate-supply voltage of 260 V, a plate current of 1 mA, and a plate load resistance of 100,000 ohms?a plate current of 1 mA, and a plate load resistance of 100,000 ohms? A.160 V A.160 V B.100 V B.100 V C.200 V C.200 V D.60 V D.60 V

6A2336A233AAWhy is it necessary to use two tubes in a Class B audio amplifier?Why is it necessary to use two tubes in a Class B audio amplifier? A.To prevent the excessive distortion which would result from the use of only one tube in Class B A.To prevent the excessive distortion which would result from the use of only one tube in Class B B.To eliminate hum B.To eliminate hum C.A & B C.A & B D.None of the above D.None of the above

6A2346A234DDIf the coupling capacitor leaked in a resistance-coupled audio frequency amplifier:If the coupling capacitor leaked in a resistance-coupled audio frequency amplifier: A.Excessive plate current would result A.Excessive plate current would result B.A large value of grid current would result B.A large value of grid current would result C.There would be extreme distortion, and very low gain C.There would be extreme distortion, and very low gain D.All of the above D.All of the above

6A2356A235CC

A vacuum tube operated Class C audio amplifier is not feasible, either in single or push-pull:A vacuum tube operated Class C audio amplifier is not feasible, either in single or push-pull: A.Since the plate current only flows 120 degrees, even in push-pull, only 2/3 of the cycle is reproduced A.Since the plate current only flows 120 degrees, even in push-pull, only 2/3 of the cycle is reproduced and the resultant distortion would be unacceptable for audioand the resultant distortion would be unacceptable for audio B.Tank circuits, which replace the missing portions of the cycle, can't be used in an audio amplifier B.Tank circuits, which replace the missing portions of the cycle, can't be used in an audio amplifier because they only operate on one frequencybecause they only operate on one frequency C.A & B C.A & B D.None of the above D.None of the above

6A2366A236CCEven harmonics may be reduced in the output of an audio frequency amplifier:Even harmonics may be reduced in the output of an audio frequency amplifier: A.By operating the state push-pull A.By operating the state push-pull B.In a single tube amplifier, by operating the stage only on the linear part of the tube's characteristic B.In a single tube amplifier, by operating the stage only on the linear part of the tube's characteristic curvecurve C.A & B C.A & B D.None of the above D.None of the above

6A2376A237AAThe main advantage of a tuned audio frequency amplifier in a receiver used for the reception of CW:The main advantage of a tuned audio frequency amplifier in a receiver used for the reception of CW: A.A reduction in interference from unwanted signals A.A reduction in interference from unwanted signals B.The desired audio beat frequency is attenuates B.The desired audio beat frequency is attenuates C.A & B C.A & B D.None of the above D.None of the above

6A2386A238AADecoupling networks in the plate circuit of a multistage audio amplifier:Decoupling networks in the plate circuit of a multistage audio amplifier: A.Prevents oscillations from occurring in the amplifier A.Prevents oscillations from occurring in the amplifier B.Result in oscillations in the amplifier B.Result in oscillations in the amplifier C.Allow variable oscillations in the amplifier C.Allow variable oscillations in the amplifier D.None of the above D.None of the above

6A2396A239AAAn audio-transformer is seldom used as the output device in the plate circuit of a tetrode audio-amplifier An audio-transformer is seldom used as the output device in the plate circuit of a tetrode audio-amplifier stage:stage: A.Because an ordinary transformer cannot supply enough impedance to the plate circuit A.Because an ordinary transformer cannot supply enough impedance to the plate circuit B.Because an ordinary transformer supplies too much impedance to the plate circuit B.Because an ordinary transformer supplies too much impedance to the plate circuit C.Because an ordinary transformer would be too costly C.Because an ordinary transformer would be too costly D.None of the above D.None of the above

6A2406A240BB

The chief advantage of Class A audio operation is compared to the other classes of audio-frequency The chief advantage of Class A audio operation is compared to the other classes of audio-frequency amplifiers:amplifiers: A.Hum currents are in phase A.Hum currents are in phase B.Low distortion of the output signal B.Low distortion of the output signal C.Tendency for regeneration is increased C.Tendency for regeneration is increased D.Elimination of cathode bypass capacitors D.Elimination of cathode bypass capacitors

6A2416A241DDWhich is not the principle advantage of transformer coupling compared to resistance coupling in audio-Which is not the principle advantage of transformer coupling compared to resistance coupling in audio-frequency amplifiers? A.Greater gain per stagefrequency amplifiers? A.Greater gain per stage B.Can provide necessary impedance matching B.Can provide necessary impedance matching C.A & B C.A & B D.A transformer is expensive, heavy, and bulky D.A transformer is expensive, heavy, and bulky

6A2426A242DDEfficiency of a power transformer is determined by:Efficiency of a power transformer is determined by: A.Eddy current losses A.Eddy current losses B.Hysteresis losses B.Hysteresis losses C.Copper losses C.Copper losses D.All of the above D.All of the above

6A2436A243DDThe ratios of primary and secondary currents in a power transformer:The ratios of primary and secondary currents in a power transformer: A.Are approximately in inverse ratio to the turns ratio A.Are approximately in inverse ratio to the turns ratio B.Is to some extent affected by the diameter of the primary and secondary wire B.Is to some extent affected by the diameter of the primary and secondary wire C.The current ratio is in inverse proportion to the voltage ratio C.The current ratio is in inverse proportion to the voltage ratio D.All of the above D.All of the above

6A2446A244AAA transformer has a primary voltage of 100, primary turns = 200, and secondary turns = 40. What is the A transformer has a primary voltage of 100, primary turns = 200, and secondary turns = 40. What is the secondary voltage?secondary voltage? A.20 V A.20 V B.240 V B.240 V C.140 V C.140 V D.340 V D.340 V

6A2456A245BBWhat factors determine the no-load voltage ratio of a power transformer?What factors determine the no-load voltage ratio of a power transformer?

A.Power ratio A.Power ratio B.Turns ratio B.Turns ratio C.Voltage ratio C.Voltage ratio D.Power factor D.Power factor

6A2466A246AAThe turns ratio of a transformer varies:The turns ratio of a transformer varies: A.As the square root of the impedance ratio A.As the square root of the impedance ratio B.As the square of the impedance ratio B.As the square of the impedance ratio C.As one-half the impedance ratio C.As one-half the impedance ratio D.As twice the impedance ratio D.As twice the impedance ratio

6A2476A247DDPrimary cells:Primary cells: A.Can be recharged A.Can be recharged B.Cannot be recharged B.Cannot be recharged C.An attempt to recharge it would not restore the eroded electrode C.An attempt to recharge it would not restore the eroded electrode D.B & D D.B & D

6A2486A248DDSecondary cells:Secondary cells: A.Can be recharged A.Can be recharged B.Cannot be recharged B.Cannot be recharged C.The products of the chemical change are not soluble in the electrolyte C.The products of the chemical change are not soluble in the electrolyte D.A & C D.A & C

6A2496A249BBThe formation of hydrogen gas around the positive electrode of a primary cell is:The formation of hydrogen gas around the positive electrode of a primary cell is: A.Depolarization A.Depolarization B.Polarization B.Polarization C.Manganese dioxide C.Manganese dioxide D.None of the above D.None of the above

6A2506A250DDA dry cell may be tested:A dry cell may be tested: A.Must be tested under normal load condition A.Must be tested under normal load condition B.May be tested under no load condition B.May be tested under no load condition C.May be taken by any conventional voltmeter C.May be taken by any conventional voltmeter D.A & C D.A & C

6A2516A251DDIn the usual type dry cell:In the usual type dry cell: A.The negative electrode is made of zinc A.The negative electrode is made of zinc B.The positive electrode is made of carbon B.The positive electrode is made of carbon

C.The negative electrode is made of zinc C.The negative electrode is made of zinc D.A & B D.A & B

6A2526A252DD"A", "B", and "C" batteries are alike, but specifically constructed for a particular function. Explain:"A", "B", and "C" batteries are alike, but specifically constructed for a particular function. Explain: A."B" battery is for plate and screen power A."B" battery is for plate and screen power B."C" battery for grid bias voltage B."C" battery for grid bias voltage C."A" battery for filament power C."A" battery for filament power D.All of the above D.All of the above

6A2536A253DDThe condition of a dry "B" battery may be determined:The condition of a dry "B" battery may be determined: A.By measuring the voltage under normal load A.By measuring the voltage under normal load B.By measuring the voltage under no load B.By measuring the voltage under no load C.A loss of 20 % of the voltage under normal load indicates that the battery should be replaced C.A loss of 20 % of the voltage under normal load indicates that the battery should be replaced D.A & C D.A & C

6A2546A254AASpare "B" batteries should be stored:Spare "B" batteries should be stored: A.In a dry place A.In a dry place B.In a hot place B.In a hot place C.Anywhere C.Anywhere D.A & C D.A & C

6A2556A255AAA means of comparing the weight of a volume of liquid with the same volume of distilled water:A means of comparing the weight of a volume of liquid with the same volume of distilled water: A.Specific gravity A.Specific gravity B.Specific mass B.Specific mass C.Specific volume C.Specific volume D.None of the above D.None of the above

6A2566A256DDEdison type batteries:Edison type batteries: A.Have plates up nickel A.Have plates up nickel B.Have plates of iron B.Have plates of iron C.Have plates of compounds of nickel and iron C.Have plates of compounds of nickel and iron D.All of the above D.All of the above

6A2576A257DDThe electrolyte of a lead-acid storage cell:The electrolyte of a lead-acid storage cell: A.Concentrated sulfuric acid A.Concentrated sulfuric acid B.Dilute sulfuric acid B.Dilute sulfuric acid C.Has a specific gravity about 1.3 fully charged C.Has a specific gravity about 1.3 fully charged

D.B & C D.B & C

6A2586A258AAThe negative plate of a lead-acid storage cell:The negative plate of a lead-acid storage cell: A.Is composed of pure spongy lead A.Is composed of pure spongy lead B.Is composed of lead peroxide B.Is composed of lead peroxide C.Is composed of a compound of pure spongy lead and lead peroxide C.Is composed of a compound of pure spongy lead and lead peroxide D.None of the above D.None of the above

6A2596A259BBThe positive plate of a lead-acid storage cell:The positive plate of a lead-acid storage cell: A.Is composed of pure spongy lead A.Is composed of pure spongy lead B.Is composed of lead peroxide B.Is composed of lead peroxide C.Is composed of a compound of pure spongy lead and lead peroxide C.Is composed of a compound of pure spongy lead and lead peroxide D.None of the above D.None of the above

6A2606A260DDThe chemical composition of the electrolyte in an Edison-type storage cell:The chemical composition of the electrolyte in an Edison-type storage cell: A.Is contained in a nickel-plated sheet steel tank A.Is contained in a nickel-plated sheet steel tank B.Has a specific gravity of about 1.200 B.Has a specific gravity of about 1.200 C.Is a 21% solution of potassium and lithium hydroxides in distilled water C.Is a 21% solution of potassium and lithium hydroxides in distilled water D.All of the above D.All of the above

6A2616A261AAThe negative plate of an Edison-type storage cell is:The negative plate of an Edison-type storage cell is: A.Finely powdered pure iron A.Finely powdered pure iron B.Green oxide of nickel B.Green oxide of nickel C.Potassium oxide C.Potassium oxide D.None of the above D.None of the above

6A2626A262BBThe positive plate of an Edison-type storage cell is:The positive plate of an Edison-type storage cell is: A.Finely powdered pure iron A.Finely powdered pure iron B.Green oxide of nickel B.Green oxide of nickel C.Lithium oxide C.Lithium oxide D.None of the above D.None of the above

6A2636A263AAThe average fully-charged voltage of an Edison storage cell is:The average fully-charged voltage of an Edison storage cell is: A.1.2 V A.1.2 V B.1.5 V B.1.5 V C.2 V C.2 V D.1 V D.1 V

6A2646A264DDDecrease in capacity of an Edison-type storage cell can be caused by:Decrease in capacity of an Edison-type storage cell can be caused by: A.Frequent overheating, and operating conditions over 115 degrees fahrenheit A.Frequent overheating, and operating conditions over 115 degrees fahrenheit B.Charging at less than the normal rate B.Charging at less than the normal rate C.Adding impure water to the electrolyte, or a weak or aged electrolyte C.Adding impure water to the electrolyte, or a weak or aged electrolyte D.All of the above D.All of the above

6A2656A265CCThe average fully charged voltage of a lead-acid cell is:The average fully charged voltage of a lead-acid cell is: A.1.0 V A.1.0 V B.1.56 V B.1.56 V C.2.06 V C.2.06 V D.2.5 V D.2.5 V

6A266 6A266AATo increase the power output of a storage cell:To increase the power output of a storage cell: A.Low internal resistance is desirable A.Low internal resistance is desirable B.High internal resistance is desirable B.High internal resistance is desirable C.Low terminal voltage under load is desirable C.Low terminal voltage under load is desirable D.None of the above D.None of the above

6A267 6A267CCThe condition of charge of an Edison cell can be determined:The condition of charge of an Edison cell can be determined: A.By reading the terminal voltage under load A.By reading the terminal voltage under load B.By checking the voltage against a standard discharge curve B.By checking the voltage against a standard discharge curve C.Both A & B C.Both A & B D.Checking the specific gravity D.Checking the specific gravity

6A268 6A268CCThe charge of a lead-acid storage cell:The charge of a lead-acid storage cell: A.May be determined by hydrometer readings A.May be determined by hydrometer readings B.By measuring voltage under a heavy load B.By measuring voltage under a heavy load C.A or B C.A or B D.None of the above D.None of the above

6A269 6A269DDSulfation:Sulfation: A.Reduces terminal voltage A.Reduces terminal voltage

B.Increases internal resistance B.Increases internal resistance C.Reduces power output C.Reduces power output D.All of the above D.All of the above

6A270 6A270DDIf the polarity is reversed when charging a storage cell:If the polarity is reversed when charging a storage cell: A.No damage in a lead-acid cell unless excessive A.No damage in a lead-acid cell unless excessive B.Damage in an Edison-cell B.Damage in an Edison-cell C.No damage in an Edison-cell if temperatures below 115 degrees Fahrenheit C.No damage in an Edison-cell if temperatures below 115 degrees Fahrenheit D.A & C D.A & C

6A271 6A271AAYou may measure the voltage of a battery under heavy load:You may measure the voltage of a battery under heavy load: A.To determine its condition of charge A.To determine its condition of charge B.To determine its polarity B.To determine its polarity C.To determine its age C.To determine its age D.None of the above D.None of the above

6A272 6A272AAIf the voltage of some cells in a battery are found to be reversed, what is indicated?If the voltage of some cells in a battery are found to be reversed, what is indicated? A.Polarity was reversed while charging A.Polarity was reversed while charging B.Polarity was doubled while charging B.Polarity was doubled while charging C.Polarity has no influence of charging C.Polarity has no influence of charging D.Polarity was correct while charging D.Polarity was correct while charging

6A273 6A273DDDistilled water should be added to a lead-acid storage cell:Distilled water should be added to a lead-acid storage cell: A.To keep the electrolyte 1/4 inch above the to of the plates A.To keep the electrolyte 1/4 inch above the to of the plates B.To keep the useful plate area sufficient to maintain the full capacity of the cell B.To keep the useful plate area sufficient to maintain the full capacity of the cell C.None of the above C.None of the above D.A & B D.A & B

6A274 6A274DDLocal action in a lead-acid storage cell:Local action in a lead-acid storage cell: A.Causes a slow discharge in the cell A.Causes a slow discharge in the cell B.Forms a very hard sulfate on the plates B.Forms a very hard sulfate on the plates C.May be reduced by trickle charging when the battery is not in actual use C.May be reduced by trickle charging when the battery is not in actual use D.All of the above D.All of the above

6A275 6A275DDTo maintain a group of storage cells in good operating condition:To maintain a group of storage cells in good operating condition: A.Observe correct charge and discharge rates A.Observe correct charge and discharge rates B.Overcharge about once a month to remove sulfation B.Overcharge about once a month to remove sulfation C.Keep all terminal corrections clean and tight C.Keep all terminal corrections clean and tight D.All of the above D.All of the above 6A276 6A276DDWhat may cause the plates of a lead-acid call to buckle?What may cause the plates of a lead-acid call to buckle? A.Excessive sulfation A.Excessive sulfation B.Overheating B.Overheating C.Overdischarging of the battery C.Overdischarging of the battery D.All of the above D.All of the above

6A277 6A277DDWhat may cause sulfation of a lead-acid cell?What may cause sulfation of a lead-acid cell? A.It is a normal process A.It is a normal process B.Overdischarging B.Overdischarging C.Local action with improper charging C.Local action with improper charging D.All of the above D.All of the above

6A278 6A278DDWhat may be used to neutralize an acid electrolyte?What may be used to neutralize an acid electrolyte? A.Ammonium hydroxide A.Ammonium hydroxide B.Baking soda B.Baking soda C.Washing soda C.Washing soda D.All of the above D.All of the above

6A279 6A279AATo prevent corrosion of battery terminals:To prevent corrosion of battery terminals: A.Occasionally clean and coat them with Vaseline or other suitable lubricants A.Occasionally clean and coat them with Vaseline or other suitable lubricants B.Use only brass terminals B.Use only brass terminals C.Use only stainless steel terminals C.Use only stainless steel terminals D.Keep battery on trickles charge D.Keep battery on trickles charge

6A280 6A280DDWhy should there be ventilation to the room housing a large group of storage cells?Why should there be ventilation to the room housing a large group of storage cells? A.To prevent gas accumulation A.To prevent gas accumulation B.To prevent overheating B.To prevent overheating C.To prevent the terminals from shorting C.To prevent the terminals from shorting D.A & B D.A & B

6A281 6A281

DDRadio equipment on which electrolyte may be used:Radio equipment on which electrolyte may be used: A.Electrolyte capacitor A.Electrolyte capacitor B.Electrolyte rectifier B.Electrolyte rectifier C.Electrolyte detector C.Electrolyte detector D.All of the above D.All of the above 6A2826A282CCWhat is the effect of low temperature on the operation of a lead-acid storage battery?What is the effect of low temperature on the operation of a lead-acid storage battery? A.Electrolyte may freeze and split the battery if sg too low A.Electrolyte may freeze and split the battery if sg too low B.The capacity is decreased B.The capacity is decreased C.A & B C.A & B D.None of the above D.None of the above

6A283 6A283AAWhat form of energy is stored in a lead-acid storage battery?What form of energy is stored in a lead-acid storage battery? A.Chemical A.Chemical B.Mechanical B.Mechanical C.Heat C.Heat D.Light D.Light

6A284 6A284CCHow may polarity of a storage battery be determined?How may polarity of a storage battery be determined? A.Voltmeter A.Voltmeter B.Salt water method B.Salt water method C.A & B C.A & B D.None of the above D.None of the above

6A285 6A285AAA battery with a terminal voltage of 12.5 V is to be trickle-charged at a 0.5 A rate. What resistance A battery with a terminal voltage of 12.5 V is to be trickle-charged at a 0.5 A rate. What resistance should be connected in series with the battery to charge from a 110 V line?should be connected in series with the battery to charge from a 110 V line? A.195 ohms A.195 ohms B.300 ohms B.300 ohms C.95 ohms C.95 ohms D.None of the above D.None of the above

6A286 6A286AAA discharged storage battery of 3 cells has an open circuit voltage of 1.8 V per cell and an internal A discharged storage battery of 3 cells has an open circuit voltage of 1.8 V per cell and an internal resistance of 0.1 ohm per cell. What voltage is needed to give an initial charging rate of 10 A?resistance of 0.1 ohm per cell. What voltage is needed to give an initial charging rate of 10 A? A.8.4 V A.8.4 V B.10 V B.10 V C.15 V C.15 V D.12.5 V D.12.5 V

6A2876A287CCWhat capacity in amperes of storage battery is required to operate a 50 W emergency transmitter for 6 What capacity in amperes of storage battery is required to operate a 50 W emergency transmitter for 6 hr.? Assume a continuous transmitter load of 70% of the key-locked demand of 40 A, and an emergency hr.? Assume a continuous transmitter load of 70% of the key-locked demand of 40 A, and an emergency light load of 1.5 A.light load of 1.5 A. A.A battery rated greater than 177 amperhours A.A battery rated greater than 177 amperhours B.A battery rated at least 177 amperhours B.A battery rated at least 177 amperhours C.A & B C.A & B D.None of the above D.None of the above

6A288 6A288AAIf a receiver storage A battery could not be kept charged, and maintain the required watch period, what If a receiver storage A battery could not be kept charged, and maintain the required watch period, what should you do?should you do? A.Increase the charging rate A.Increase the charging rate B.Get a new battery B.Get a new battery C.Discontinue the required watch period C.Discontinue the required watch period D.B & C D.B & C

6A289 6A289DDAbnormally low input power terminal voltage of a lifeboat radiotelegraph transmitter while in operation Abnormally low input power terminal voltage of a lifeboat radiotelegraph transmitter while in operation could be caused by:could be caused by: A.Reversed polarity A.Reversed polarity B.Excessive overload B.Excessive overload C.A partially discharged battery C.A partially discharged battery D.B & C D.B & C

6A290 6A290AAIf a battery has 12.4 V on open circuit and 12.2 V when its charging circuit is closed:If a battery has 12.4 V on open circuit and 12.2 V when its charging circuit is closed: A.Could have polarity reversed A.Could have polarity reversed B.Could be overloaded B.Could be overloaded C.A & B C.A & B D.None of the above D.None of the above

6A291 6A291DDThe tops of lead-acid batteries should be kept dry:The tops of lead-acid batteries should be kept dry: A.To prevent slow discharge of the battery A.To prevent slow discharge of the battery

B.To prevent terminal overload B.To prevent terminal overload C.To reduce the formation of terminal corrosion C.To reduce the formation of terminal corrosion D.A & C D.A & C

6A292 6A292CCWhen lead-acid cells are subject to low temperatures they should:When lead-acid cells are subject to low temperatures they should: A.To prevent freezing A.To prevent freezing B.To provide the maximum capacity B.To provide the maximum capacity C.A & B C.A & B D.None of the above D.None of the above

6A293 6A293AAIf an electrolyte in a lead-acid storage cell becomes low due to evaporation:If an electrolyte in a lead-acid storage cell becomes low due to evaporation: A.The level should be brought to about 1/4 inch above the tops of the plates with pure water A.The level should be brought to about 1/4 inch above the tops of the plates with pure water B.The level should be brought to about 1/4 inch above the tops of the plates with tap water B.The level should be brought to about 1/4 inch above the tops of the plates with tap water C.The level should be brought to about 1/4 inch above the tops of the plates with salt water C.The level should be brought to about 1/4 inch above the tops of the plates with salt water D.None of the above D.None of the above

6A294 6A294CCAn Edison storage battery should not be charged at less than the manufacturer's specified rate:An Edison storage battery should not be charged at less than the manufacturer's specified rate: A.In order that the capacity of the battery shall be maximum after charge A.In order that the capacity of the battery shall be maximum after charge B.The chemical reactions of the Edison-type cell B.The chemical reactions of the Edison-type cell C.A & B C.A & B D.None of the above D.None of the above

6A295 6A295DDYour emergency battery has a specific gravity reading of 1.120. What should be done?Your emergency battery has a specific gravity reading of 1.120. What should be done? A.Place the battery on charge at once A.Place the battery on charge at once B.Bring the electrolyte level to about 1/4 inch above the top of the plates B.Bring the electrolyte level to about 1/4 inch above the top of the plates C.The battery will be fully charged when the specific gravity reads 1.280 to 1.300 C.The battery will be fully charged when the specific gravity reads 1.280 to 1.300 D.All of the above D.All of the above

6A296 6A296AAWhat care should be taken with selecting water to add to a storage cell?What care should be taken with selecting water to add to a storage cell? A.It should be chemically pure or distilled A.It should be chemically pure or distilled B.It should be only sea water B.It should be only sea water C.Tap water is as good as any C.Tap water is as good as any D.None of the above D.None of the above

6A297 6A297DDIf the circuit breakers refuse to stay closed when you place the emergency batteries on charge, what is theIf the circuit breakers refuse to stay closed when you place the emergency batteries on charge, what is the trouble?trouble? A.Internally shorted cells A.Internally shorted cells B.Reversed charging polarity B.Reversed charging polarity C.Grounded circuit connections C.Grounded circuit connections D.Any of the above D.Any of the above

6A298 6A298CCHeat developed within a storage cell under charge or discharge conditions is caused by:Heat developed within a storage cell under charge or discharge conditions is caused by: A.I2R losses A.I2R losses B.Energy transfer due to chemical reactions B.Energy transfer due to chemical reactions C.A & B C.A & B D.None of the above D.None of the above

6A299 6A299AAHow would you connect a group of similar cells in a storage battery to obtain the maximum zero How would you connect a group of similar cells in a storage battery to obtain the maximum zero resistance current?resistance current? A.In parallel A.In parallel B.In series B.In series C.In series/parallel C.In series/parallel D.None of the above D.None of the above

6A300 6A300BBHow would you connect a group of similar cells in a storage battery to obtain the maximum no-bond How would you connect a group of similar cells in a storage battery to obtain the maximum no-bond output voltage?output voltage? A.In parallel A.In parallel B.In series B.In series C.In series/parallel C.In series/parallel D.None of the above D.None of the above

6A301 6A301AAWhat current will flow in a 6 V storage battery with an internal resistance of 0.01 ohms, when a 3 W, 6 VWhat current will flow in a 6 V storage battery with an internal resistance of 0.01 ohms, when a 3 W, 6 V lamp is connected?lamp is connected? A.0.4995 A A.0.4995 A B.0.4885 A B.0.4885 A C.0.5566 A C.0.5566 A D.0.5795 A D.0.5795 A

6A302 6A302CCThe charging rate of a storage cell charged from a fixed voltage source decreases as the charging The charging rate of a storage cell charged from a fixed voltage source decreases as the charging progresses opposition to the charging voltage?progresses opposition to the charging voltage? A.Because as cell voltages increase, offering more opposition to the charging voltage A.Because as cell voltages increase, offering more opposition to the charging voltage B.When the effective charging potential is reduced, the charging current is decreased B.When the effective charging potential is reduced, the charging current is decreased C.Both A & B C.Both A & B D.None of the above D.None of the above

6A303 6A303CCThe principal function of the filter in a power supply:The principal function of the filter in a power supply: A.To remove the variations in amplitude of the rectifier output A.To remove the variations in amplitude of the rectifier output B.To provide a relatively unvarying DC voltage for use in the various circuits B.To provide a relatively unvarying DC voltage for use in the various circuits C.Either A or B C.Either A or B D.None of the above D.None of the above

6A304 6A304CCAdvantages of capacitor input and choke-input filters when used with rectifiers:Advantages of capacitor input and choke-input filters when used with rectifiers: A.Capacitor-input filter provides higher output voltage under reasonably light load conditions A.Capacitor-input filter provides higher output voltage under reasonably light load conditions B.Choke-input filter offers better voltage regulations B.Choke-input filter offers better voltage regulations C.A & B C.A & B D.None of the above D.None of the above

6A305 6A305AAA high-resistance fixed resistor is shunted across each unit of a high voltage series capacitor bank in the A high-resistance fixed resistor is shunted across each unit of a high voltage series capacitor bank in the power-supply filter circuit to:power-supply filter circuit to: A.Insure that the correct voltage appears across each unit A.Insure that the correct voltage appears across each unit B.Discharge the capacitors B.Discharge the capacitors C.Does not insure the correct voltage across each unit C.Does not insure the correct voltage across each unit D.None of the above D.None of the above

6A306 6A306AAPart of the secondary winding of a transmitters power transformer is accidentally shorted. What should Part of the secondary winding of a transmitters power transformer is accidentally shorted. What should be the immediate effect?be the immediate effect? A.The current would rise to an excessive value and trip the circuit breaker A.The current would rise to an excessive value and trip the circuit breaker B.The short would burn the transformer B.The short would burn the transformer C.The current in the secondary winding would decrease C.The current in the secondary winding would decrease D.None of the above D.None of the above

6A307 6A307

CCBleeder resistors are used in power supplies:Bleeder resistors are used in power supplies: A.To improve the output voltage regulation A.To improve the output voltage regulation B.They also discharge the filter capacitor when the power is turned off B.They also discharge the filter capacitor when the power is turned off C.Either A or B C.Either A or B D.None of the above D.None of the above

6A308 6A308BBThe ratio of the frequencies of the output and input circuits of a single-phase full-wave rectifier:The ratio of the frequencies of the output and input circuits of a single-phase full-wave rectifier: A.1 to 1 A.1 to 1 B.2 to 1 B.2 to 1 C.1 to 2 C.1 to 2 D.None of the above D.None of the above

6A309 6A309AAA capacitor is sometimes placed in series with the primary of a power transformer:A capacitor is sometimes placed in series with the primary of a power transformer: A.To improve the power factor A.To improve the power factor B.To improve output voltage regulation B.To improve output voltage regulation C.To rectify the primary windings C.To rectify the primary windings D.None of the above D.None of the above

6A310 6A310AAWhat is the maximum allowable secondary voltage of a transformer used as a center-tapped full-wave What is the maximum allowable secondary voltage of a transformer used as a center-tapped full-wave rectifier with tubes having a peak inverse voltage rating of 10,000 V?rectifier with tubes having a peak inverse voltage rating of 10,000 V? A.7070 V A.7070 V B.14140 V B.14140 V C.10000 V C.10000 V D.5000 V D.5000 V

6A311 6A311DDIf a 60 Hz transformer is connected to a 120 Hz source of the same voltage:If a 60 Hz transformer is connected to a 120 Hz source of the same voltage: A.The impedance of the transformers would be greater A.The impedance of the transformers would be greater B.The current would be reduced B.The current would be reduced C.There would be a decrease in power delivered to the load C.There would be a decrease in power delivered to the load D.All the above D.All the above

6A312 6A312DDIf a 500 Hz transformer is connected to a 60 Hz source of the same voltage:If a 500 Hz transformer is connected to a 60 Hz source of the same voltage: A.The primary would draw excessive current A.The primary would draw excessive current

B.The transformer would overheat B.The transformer would overheat C.The primary might burn out C.The primary might burn out D.All of the above D.All of the above

6A313 6A313DDA 500 Hz AC plate supply, rectified by a full-wave, unfiltered rectifier circuit. What would the emission A 500 Hz AC plate supply, rectified by a full-wave, unfiltered rectifier circuit. What would the emission be?be? A.A modulated continuous wave of 500 Hz A.A modulated continuous wave of 500 Hz B.A modulated continuous wave of 1000 Hz B.A modulated continuous wave of 1000 Hz C.A-2 C.A-2 D.All of the above D.All of the above

6A314 6A314AAThe purpose of an air gap in a filter choke coil core. Which is the incorrect answer?The purpose of an air gap in a filter choke coil core. Which is the incorrect answer? A.To decrease the effective inductance for the AC component of current by increasing the DC saturation A.To decrease the effective inductance for the AC component of current by increasing the DC saturation B.To increase the effective inductance for the AC component of current by decreasing the DC saturation B.To increase the effective inductance for the AC component of current by decreasing the DC saturation C.The inductance of the coil in general's decreased C.The inductance of the coil in general's decreased D.All of the above D.All of the above

6A315 6A315CCLoose laminations in a filter choke:Loose laminations in a filter choke: A.Make it impossible to firmly connect the choke in a circuit A.Make it impossible to firmly connect the choke in a circuit B.A & C B.A & C C.Cause a buzzing or chattering sound C.Cause a buzzing or chattering sound D.None of the above D.None of the above

6A316 6A316DDPoor regulation in a power supply may be caused by:Poor regulation in a power supply may be caused by: A.No bleeder resistance A.No bleeder resistance B.High resistance filter chokes B.High resistance filter chokes C.Insufficient filter capacity C.Insufficient filter capacity D.All of the above D.All of the above

6A3176A317CCWhy should the case of a high-voltage transformer be grounded?Why should the case of a high-voltage transformer be grounded? A.To protect personnel handling the equipment from shock A.To protect personnel handling the equipment from shock B.To prevent high static voltages building up between the case and grounds B.To prevent high static voltages building up between the case and grounds

C.A & B C.A & B D.None of the above D.None of the above

6A318 6A318AAWhen connecting electrolytic capacitors in series:When connecting electrolytic capacitors in series: A.Observe the polarity marked on the component A.Observe the polarity marked on the component B.There is no polarity to observe B.There is no polarity to observe C.Connect anode to anode C.Connect anode to anode D.Connect cathode to cathode D.Connect cathode to cathode

6A319 6A319CCFull wave rectification has ____ than half-wave:Full wave rectification has ____ than half-wave: A.Better output voltage regulation A.Better output voltage regulation B.Smaller filter components for a given ripple percentage B.Smaller filter components for a given ripple percentage C.A and B C.A and B D.None of the above D.None of the above

6A320 6A320AAVoltage regulation is ____ with a high resistance choke:Voltage regulation is ____ with a high resistance choke: A.Made worse A.Made worse B.Made better B.Made better C.The same C.The same D.None of the above D.None of the above

6A321 6A321DDElectrolyte capacitors are desirable over other types because:Electrolyte capacitors are desirable over other types because: A.A large capacitance may be obtained with small physical dimensions A.A large capacitance may be obtained with small physical dimensions B.They have a cathode B.They have a cathode C.The wet-type electrolytic capacitor is "self-healing" C.The wet-type electrolytic capacitor is "self-healing" D.A & C D.A & C

6A322 6A322AAThe most common values of chokes range from:The most common values of chokes range from: A.5 H to 30 H A.5 H to 30 H B.30 H-100 H B.30 H-100 H C.1 H to 100 H C.1 H to 100 H

D.100 H to 1000 H D.100 H to 1000 H

6A323 6A323DDThe power transformer and rectifier of a radio receiver are designed to supply a plate voltage of 250 V The power transformer and rectifier of a radio receiver are designed to supply a plate voltage of 250 V when operating from a 110 V 60 Hz supply, if the transformer is connected to 110 VDC what will when operating from a 110 V 60 Hz supply, if the transformer is connected to 110 VDC what will happen?happen? A.The secondary would burn out A.The secondary would burn out B.The primary would overheat and burn out B.The primary would overheat and burn out C.The circuit breaker would open to protect the circuit C.The circuit breaker would open to protect the circuit D.Either A or B D.Either A or B

6A324 6A324AAA shunt-wound DC motor:A shunt-wound DC motor: A.Has a practically constant speed under widely varying load conditions A.Has a practically constant speed under widely varying load conditions B.Has poor speed regulation under varying load conditions B.Has poor speed regulation under varying load conditions C.High starting torque C.High starting torque D.None of the above D.None of the above

6A325 6A325DDA series DC motor has:A series DC motor has: A.Maximum torque at low speed A.Maximum torque at low speed B.Quick starting B.Quick starting C.Poor speed regulation under varying loads C.Poor speed regulation under varying loads D.All of the above D.All of the above

6A326 6A326BBThis partially counteracts the line voltage and so limits the armature current in a DC motor:This partially counteracts the line voltage and so limits the armature current in a DC motor: A.EMF A.EMF B.Counter EMF B.Counter EMF C.Opposition EMF C.Opposition EMF D.None of the above D.None of the above

6A327 6A327DDA compound-wound DC motor:A compound-wound DC motor: A.Has constant speed under changing load conditions A.Has constant speed under changing load conditions B.Low starting torque B.Low starting torque C.High starting torque C.High starting torque D.A & B D.A & B

6A328 6A328CCLaminated iron is used in armature and field construction to:Laminated iron is used in armature and field construction to: A.Reduce eddy current losses A.Reduce eddy current losses B.Offer a number of high-resistance paths to Eddy currents B.Offer a number of high-resistance paths to Eddy currents C.A or B C.A or B D.None of the above D.None of the above

6A329 6A329BBThe ____ of a DC motor periodically change the armature coils to maintain one direction of rotation:The ____ of a DC motor periodically change the armature coils to maintain one direction of rotation: A.Field coils A.Field coils B.Connector B.Connector C.Brushes C.Brushes D.Auxiliary speed control D.Auxiliary speed control

6A330 6A330AAThe speed of a series DC motor may increase and destroy the motor by centrifugal action:The speed of a series DC motor may increase and destroy the motor by centrifugal action: A.When operated without a load A.When operated without a load B.When operated on AC B.When operated on AC C.When operated under varying load C.When operated under varying load D.None of the above D.None of the above

6A331 6A331AAWhen the field of a shunt-wound DC motor opens while the machine is operating under no load:When the field of a shunt-wound DC motor opens while the machine is operating under no load: A.The motor would race, and if unchoked, might destroy itself A.The motor would race, and if unchoked, might destroy itself B.The motor would quit running without damage B.The motor would quit running without damage C.The motor would burn out the field coils C.The motor would burn out the field coils D.None of the above D.None of the above

6A332 6A332CC____ are used in a DC motor to reduce brush sparking without moving the brushes:____ are used in a DC motor to reduce brush sparking without moving the brushes: A.Interpoles A.Interpoles B.Commutating poles B.Commutating poles C.Either A or B C.Either A or B D.None of the above D.None of the above

6A333 6A333

CCA short in the armature coils of a DC motor causes:A short in the armature coils of a DC motor causes: A.No excessive sparking at the commutator brushes A.No excessive sparking at the commutator brushes B.No overheating of the motor B.No overheating of the motor C.Reduction of speed under load, and excessive armature current C.Reduction of speed under load, and excessive armature current D.All of the above D.All of the above

6A334 6A334BBThe motor-field rheostat should be ____ when starting a DC motor generator set:The motor-field rheostat should be ____ when starting a DC motor generator set: A.Minimum resistance in the armature circuit A.Minimum resistance in the armature circuit B.Minimum resistance in the field circuit B.Minimum resistance in the field circuit C.Maximum resistance in the field circuit C.Maximum resistance in the field circuit D.None of the above D.None of the above

6A335 6A335DDIf a motor generator fails to start when the start button is depressed, the trouble may be:If a motor generator fails to start when the start button is depressed, the trouble may be: A.Blown fuse or tripped circuit breaker A.Blown fuse or tripped circuit breaker B.Open armature or motor-field rheostat B.Open armature or motor-field rheostat C.Broken connections, defective brushes C.Broken connections, defective brushes D.All of the above D.All of the above

6A336 6A336AAWhen increased output is desired from a motor-generator, what is the usual procedure?When increased output is desired from a motor-generator, what is the usual procedure? A.Decrease the resistance after rheostat in series with the generator field A.Decrease the resistance after rheostat in series with the generator field B.Increase the resistance of the rheostat in series with the generator field B.Increase the resistance of the rheostat in series with the generator field C.Output cannot be easily increased C.Output cannot be easily increased D.Shut down the motor-generator and restart under full load D.Shut down the motor-generator and restart under full load

6A337 6A337DDA dynamotor is:A dynamotor is: A.A combination motor-generator which utilizes a common field winding A.A combination motor-generator which utilizes a common field winding B.Usually run by battery power B.Usually run by battery power C.A higher efficiency than a motor-generator C.A higher efficiency than a motor-generator D.All of the above D.All of the above

6A338 6A338CCOutput voltage of a dynamotor may be regulated:Output voltage of a dynamotor may be regulated:

A.Only by changing the speed of the motor A.Only by changing the speed of the motor B.A series resistance in the output line could be used to reduce the available output voltage B.A series resistance in the output line could be used to reduce the available output voltage C.Either A or B C.Either A or B D.None of the above D.None of the above

6A339 6A339DDWhat disadvantage is there to a dynamotor?What disadvantage is there to a dynamotor? A.Compactness A.Compactness B.Operating efficiency B.Operating efficiency C.It can be operated from batteries C.It can be operated from batteries D.Its output voltage is dependent on the source voltage stability D.Its output voltage is dependent on the source voltage stability

6A340 6A340DDCauses of excessive sparking at the brushes of a DC motor or generator include:Causes of excessive sparking at the brushes of a DC motor or generator include: A.Brushes not properly set at neutral point, dirt on commutator, motor overloaded A.Brushes not properly set at neutral point, dirt on commutator, motor overloaded B.Weak spring tension on brushes, brushes worn, commutator worn eccentric B.Weak spring tension on brushes, brushes worn, commutator worn eccentric C.High mica-insulation between bars, commutator bars of uneven height C.High mica-insulation between bars, commutator bars of uneven height D.All of the above D.All of the above

6A341 6A341DDBy-pass capacitors are often connected across the brushes of a high-voltage DC generator:By-pass capacitors are often connected across the brushes of a high-voltage DC generator: A.To regulate the voltage A.To regulate the voltage B.To protect the generator winding from high voltage surges B.To protect the generator winding from high voltage surges C.To reduce RF interference C.To reduce RF interference D.B & C D.B & C

6A3426A342DDCauses of motor-generator bearing overheating include:Causes of motor-generator bearing overheating include: A.Incorrect kind of lubrication, lack of ventilation A.Incorrect kind of lubrication, lack of ventilation B.Constant overload, dirt in bearings B.Constant overload, dirt in bearings C.Misalignment C.Misalignment D.All of the above D.All of the above

6A343 6A343DDRF interference may be minimized:RF interference may be minimized: A.By the use of brush by-pass capacitors A.By the use of brush by-pass capacitors B.Low frequency filters B.Low frequency filters

C.Shielding of long connecting leads C.Shielding of long connecting leads D.All of the above D.All of the above

6A344 6A344AAEmery cloth should never be used to clean the commutator of a motor or generator:Emery cloth should never be used to clean the commutator of a motor or generator: A.Because it contains particles which may lodge between commutator segments and cause short circuits A.Because it contains particles which may lodge between commutator segments and cause short circuits B.Because it may polish the commutator too smooth for good brush contact B.Because it may polish the commutator too smooth for good brush contact C.Because it may decrease the insulating quality of its mica between the interpoles C.Because it may decrease the insulating quality of its mica between the interpoles D.None of the above D.None of the above

6A345 6A345AAA 3 HP 100 V DC motor is 85% efficient when developing its rated output. What is the current?A 3 HP 100 V DC motor is 85% efficient when developing its rated output. What is the current? A.23.93 A A.23.93 A B.25 A B.25 A C.20 A C.20 A D.8.5 A D.8.5 A

6A346 6A346DDThe speed of a synchronous motor is determined:The speed of a synchronous motor is determined: A.By the number of pairs of poles A.By the number of pairs of poles B.By the line frequency B.By the line frequency C.By the load C.By the load D.A & B D.A & B

6A3476A347DDThe speed of an induction motor is determined:The speed of an induction motor is determined: A.By the number of pairs of poles A.By the number of pairs of poles B.By the line frequency B.By the line frequency C.By the load C.By the load D.All of the above D.All of the above

6A348 6A348AAThe speed of a DC series motor is determined:The speed of a DC series motor is determined: A.By the load A.By the load B.By the number of pairs of poles B.By the number of pairs of poles C.By the commutator C.By the commutator

D.None of the above D.None of the above

6A349 6A349BBWhat is the line current of a 7 HP motor operating on 120 V at full load, a power factor of 0.8, and 95% What is the line current of a 7 HP motor operating on 120 V at full load, a power factor of 0.8, and 95% efficiency?efficiency? A.56 A A.56 A B.57.2 A B.57.2 A C.58 A C.58 A D.None of the above D.None of the above

6A350 6A350AAAlternators are usually rated in:Alternators are usually rated in: A.Volt-amperes output A.Volt-amperes output B.Watts B.Watts C.Amperes C.Amperes D.***<This answer left blank by the FCC> D.***<This answer left blank by the FCC>

6A351 6A351CCWhat conditions must be met before two AC generators can be operated in parallel?What conditions must be met before two AC generators can be operated in parallel? A.Output voltages must be equal, frequencies must match A.Output voltages must be equal, frequencies must match B.Phase rotation, and relative phase positions must match B.Phase rotation, and relative phase positions must match C.A & B C.A & B D.None of the above D.None of the above

6A3526A352AAThe voltage of an alternator will:The voltage of an alternator will: A.Decrease under load A.Decrease under load B.Increase under load B.Increase under load C.Load has no effect on voltage C.Load has no effect on voltage D.None of the above D.None of the above

6A353 6A353CCWhat effect will high coupling between the plate and grid circuits of a quartz-crystal oscillator have?What effect will high coupling between the plate and grid circuits of a quartz-crystal oscillator have? A.The grid to plate capacitance will be destroyed A.The grid to plate capacitance will be destroyed B.The oscillation will be higher because of higher Q B.The oscillation will be higher because of higher Q C.Overheating of the crystal and possible breakage C.Overheating of the crystal and possible breakage D.Overmodulation D.Overmodulation

6A354 6A354BBThe operation of a dynatron oscillator depends on what?The operation of a dynatron oscillator depends on what? A.The positive emission from the anode A.The positive emission from the anode B.The secondary emission from the anode B.The secondary emission from the anode C.Cathode being in saturation C.Cathode being in saturation D.Positive resistance characteristic of the tetrode tube D.Positive resistance characteristic of the tetrode tube

6A355 6A355AATo provide additional feedback voltage in a crystal oscillator what is sometimes needed?To provide additional feedback voltage in a crystal oscillator what is sometimes needed? A.An additional plate grid feedback capacitor A.An additional plate grid feedback capacitor B.Adding a coupling circuit in series with the plate resistors B.Adding a coupling circuit in series with the plate resistors C.An astable multivibrator C.An astable multivibrator D.A monostable multivibrator D.A monostable multivibrator

6A356 6A356CCWhat is the primary reason for the use of a crystal controlled oscillator for use as a transmitter?What is the primary reason for the use of a crystal controlled oscillator for use as a transmitter? A.No cross-modulation A.No cross-modulation B.Increase in gain B.Increase in gain C.Frequency stability C.Frequency stability D.Impedance gain and wider bandpass D.Impedance gain and wider bandpass

6A357 6A357BBWhat is are the advantages of self excited oscillator and master-oscillator power-amplifier transmitters?What is are the advantages of self excited oscillator and master-oscillator power-amplifier transmitters? A.The master-oscillator has fewer parts than the self-excited and is simpler to construct A.The master-oscillator has fewer parts than the self-excited and is simpler to construct B.The self-excited oscillator transmitter is simpler to construct and has fewer parts than the master- B.The self-excited oscillator transmitter is simpler to construct and has fewer parts than the master-oscillatoroscillator C.Either A or B C.Either A or B D.Neither D.Neither

6A358 6A358DDThe primary function of the power-amplifier stage of a marine radiotelegraph transmitter is:The primary function of the power-amplifier stage of a marine radiotelegraph transmitter is: A.To transmit messages concerning the safety and health of the ship personnel A.To transmit messages concerning the safety and health of the ship personnel B.To transmit messages concerning the weather and safety of upcoming storms B.To transmit messages concerning the weather and safety of upcoming storms C.Both A and B C.Both A and B D.To improve the frequency stability of the oscillator D.To improve the frequency stability of the oscillator

6A359 6A359CCThe buffer amplifier stage of a transmitter:The buffer amplifier stage of a transmitter: A.To hold any discriminator signals until verified by the varactor diode circuits A.To hold any discriminator signals until verified by the varactor diode circuits B.Buffers any signals that may have been imposed upon the carrier signal B.Buffers any signals that may have been imposed upon the carrier signal C.To improve the frequency stability of the oscillator C.To improve the frequency stability of the oscillator D.Both A and C D.Both A and C

6A360 6A360CCWhich class of amplifier is used in the final amplifier stage for maximum plate efficiency?Which class of amplifier is used in the final amplifier stage for maximum plate efficiency? A.Class A A.Class A B.Class B B.Class B C.Class C C.Class C D.Filtered Class D D.Filtered Class D

6A361 6A361BBWhat class of amplifier is used as linear in order not to distort the modulation components?What class of amplifier is used as linear in order not to distort the modulation components? A.Class A A.Class A B.Class B B.Class B C.Class C C.Class C D.None of the above D.None of the above

6A362 6A362CCIf a class B linear final R-F amplifier were in saturation and no modulation what would happen when If a class B linear final R-F amplifier were in saturation and no modulation what would happen when modulated?modulated? A.The carrier frequency would override the grid-plate current and the result would be positive shift A.The carrier frequency would override the grid-plate current and the result would be positive shift resulting in amplificationresulting in amplification B.The Class B linear amplifier only modulates below cut-off B.The Class B linear amplifier only modulates below cut-off C.A condition of negative carrier shift would be the result C.A condition of negative carrier shift would be the result D.Both A and B D.Both A and B

6A363 6A363DDA class C amplifier:A class C amplifier: A.Has an output for the entire input signal cycle A.Has an output for the entire input signal cycle B.Output is present for less than 180 degrees of the input cycle B.Output is present for less than 180 degrees of the input cycle C.Bias is set well beyond cutoff C.Bias is set well beyond cutoff D.Both B and C D.Both B and C

6A364 6A364AAWhat effect would insufficient radio-frequency excitation have on Class C modulated amplifier output?What effect would insufficient radio-frequency excitation have on Class C modulated amplifier output? A.A negative carrier shift A.A negative carrier shift B.A positive carrier shift B.A positive carrier shift C.Both A and B C.Both A and B D.None of the above D.None of the above

6A365 6A365BBThe second harmonic of a 380 kHz frequency is:The second harmonic of a 380 kHz frequency is: A.1520 kHz A.1520 kHz B.760 kHz B.760 kHz C.190 kHz C.190 kHz D.2 D.2

6A366 6A366DDTwo effects of over-excitation of a Class B amplifier grid circuit are:Two effects of over-excitation of a Class B amplifier grid circuit are: A.Increased plate efficiency, decreased power output A.Increased plate efficiency, decreased power output B.Decreased plate efficiency, excessive grid current B.Decreased plate efficiency, excessive grid current C.Excessive plate current, excessive distortion C.Excessive plate current, excessive distortion D.Both B and C D.Both B and C

6A3676A367DDThree main factors to consider about grid-leak in a vacuum tube transmitter:Three main factors to consider about grid-leak in a vacuum tube transmitter: A.The value of grid leak current and grid leak anode to grid A.The value of grid leak current and grid leak anode to grid B.The value of grid leak resistance and duration of time the grid current is flowing B.The value of grid leak resistance and duration of time the grid current is flowing C.Internal resistance of the tube between the grid and cathode C.Internal resistance of the tube between the grid and cathode D.Both B and C D.Both B and C

6A368 6A368AAHow can an R-F amplifier stage be neutralized?How can an R-F amplifier stage be neutralized? A.Vary the tuning of the plate tank circuit while observing the amp. meter A.Vary the tuning of the plate tank circuit while observing the amp. meter B.Vary the tuning of the plate tank circuit while observing the SWR meter B.Vary the tuning of the plate tank circuit while observing the SWR meter C.Neutralization is done by circuit design either by increasing the input impedance or lowering the C.Neutralization is done by circuit design either by increasing the input impedance or lowering the inductance valueinductance value D.Both A and C are correct D.Both A and C are correct

6A369 6A369BBWhat is the purpose of a speech amplifier in connection with the modulator of a transmitter?What is the purpose of a speech amplifier in connection with the modulator of a transmitter? A.Used to raise the gain of signal after filtering A.Used to raise the gain of signal after filtering B.To raise the signal-to-noise ratio and the output voltage of microphones B.To raise the signal-to-noise ratio and the output voltage of microphones C.To feed the mixer where signal-to-noise ratio is raised C.To feed the mixer where signal-to-noise ratio is raised D.To pre-amp the weaker of the two signals received D.To pre-amp the weaker of the two signals received

6A370 6A370CCWhen the first speech-amplifier of a transmitter were overexcited, but the modulation capabilities were When the first speech-amplifier of a transmitter were overexcited, but the modulation capabilities were not exceeded what would be the effect on the output?not exceeded what would be the effect on the output? A.The waveform would be sawtooth causing undermodulation A.The waveform would be sawtooth causing undermodulation B.The waveform would be square wave creating cross-modulation B.The waveform would be square wave creating cross-modulation C.The output would be distorted C.The output would be distorted D.Both A and C D.Both A and C

6A371 6A371DDThe bias of a grid-modulated R-F stage is adjusted:The bias of a grid-modulated R-F stage is adjusted: A.Below cut-off frequency A.Below cut-off frequency B.At grid saturation B.At grid saturation C.At bias C.At bias D.1 and half to 3 times plate current cutoff value D.1 and half to 3 times plate current cutoff value

6A3726A372BBGiven the following: (1) audio power for 100% modulation equals 50% of DC input power to RF Given the following: (1) audio power for 100% modulation equals 50% of DC input power to RF modulated amplifier, (2) load presented to the modulated tube consists of the DC plate impedance of the modulated amplifier, (2) load presented to the modulated tube consists of the DC plate impedance of the modulated amplifier, (3) constant grid excitation voltage, very lot distortion, what type of modulation?modulated amplifier, (3) constant grid excitation voltage, very lot distortion, what type of modulation? A.Grid A.Grid B.Plate B.Plate C.Cathode C.Cathode D.Anode D.Anode

6A373 6A373BBModulation occurring in an RF stage other than the final power amplifier:Modulation occurring in an RF stage other than the final power amplifier: A.High level A.High level B.Low level B.Low level C.Pre-emphasis C.Pre-emphasis D.Plate D.Plate

6A374 6A374CCThe efficiency of a grid-bias modulated stage should be:The efficiency of a grid-bias modulated stage should be: A.Maximum at complete modulation A.Maximum at complete modulation B.Minimum at zero modulation B.Minimum at zero modulation C.Either A or B C.Either A or B D.None of the above D.None of the above

6A375 6A375CCDoes grid current flow in a grid-bias modulated stage under modulated conditions?Does grid current flow in a grid-bias modulated stage under modulated conditions? A.Grid current may exist during the positive porions of the AF cycle A.Grid current may exist during the positive porions of the AF cycle B.Grid current may cause distortion B.Grid current may cause distortion C.A and B C.A and B D.None of the above D.None of the above

6A376 6A376DDWhat might be the cause of a positive shift in carrier amplitude during modulation?What might be the cause of a positive shift in carrier amplitude during modulation? A.Parasitic oscillations, excessive audio drive A.Parasitic oscillations, excessive audio drive B.Incorrect tuning of final amplifier B.Incorrect tuning of final amplifier C.Insufficient RF excitation, incorrect neutralization C.Insufficient RF excitation, incorrect neutralization D.All of the above D.All of the above

6A3776A377BBFor 100% modulation, DC power input to the modulated RF amplifier should:For 100% modulation, DC power input to the modulated RF amplifier should: A.Be the same as the AC power from the modulation A.Be the same as the AC power from the modulation B.Be 1/2 the AC power from the modulation B.Be 1/2 the AC power from the modulation C.Be 1/4 the AC power from the modulation C.Be 1/4 the AC power from the modulation D.None of the above D.None of the above

6A378 6A378AAWhen a radiotelephone transmitter is 100% modulated by sinusoidal waveform , how much antenna When a radiotelephone transmitter is 100% modulated by sinusoidal waveform , how much antenna current will be observed?current will be observed? A.22.5 % increase A.22.5 % increase B.22.5 % decrease B.22.5 % decrease C.12.25% increase C.12.25% increase D.No change in antenna current D.No change in antenna current

6A379 6A379AA

What can be done in a Heising modulation system to obtain 100% modulation?What can be done in a Heising modulation system to obtain 100% modulation? A.Use a series resistor between the amplifier and modulator in the DC plate supply A.Use a series resistor between the amplifier and modulator in the DC plate supply B.Nothing needs to be done B.Nothing needs to be done C.Use a series capacitor between amplifier and modulator in the DC grid supply C.Use a series capacitor between amplifier and modulator in the DC grid supply D.Both A and C D.Both A and C

6A380 6A380CCA plate choke in a Heising modulator:A plate choke in a Heising modulator: A.Builds up audio modulating voltages A.Builds up audio modulating voltages B.Feeds audio modulating voltages to the plate of the RF modulated amplifier to produce plate B.Feeds audio modulating voltages to the plate of the RF modulated amplifier to produce plate modulationmodulation C.A and B C.A and B D.None of the above D.None of the above

6A381 6A381AAWhat value of sinusoidal audio power is required to insure 100% modulation when the DC plate input to What value of sinusoidal audio power is required to insure 100% modulation when the DC plate input to a modulated Class C amplifier has an efficiency of 60 % , and is 200 W?a modulated Class C amplifier has an efficiency of 60 % , and is 200 W? A.100 W A.100 W B.50 W B.50 W C.25 W C.25 W D.12 W D.12 W

6A3826A382CCWhat would be the antenna current when a transmitter has an antenna current of 8 amp, under A -1, even What would be the antenna current when a transmitter has an antenna current of 8 amp, under A -1, even if it is 100% modulated by sinusoidal modulation?if it is 100% modulated by sinusoidal modulation? A.9.8 amp A.9.8 amp B.The antenna current will increase by 22.5% B.The antenna current will increase by 22.5% C.Either A or B C.Either A or B D.None of the above D.None of the above

6A383 6A383DDIf a transmitter is adjusted for maximum power for telegraph, what must be done to be amplitude If a transmitter is adjusted for maximum power for telegraph, what must be done to be amplitude modulated?modulated? A.The plate voltage must be reduced A.The plate voltage must be reduced B.The plate voltage must be increased B.The plate voltage must be increased C.Tubes would have to dissipate 1.5 times as much power if the plate voltage were not reduced C.Tubes would have to dissipate 1.5 times as much power if the plate voltage were not reduced D.Both A and C D.Both A and C

6A384 6A384

DDA series-fed plate circuit of a vacuum tube amplifier has a short circuit of the plate bypass capacitor. A series-fed plate circuit of a vacuum tube amplifier has a short circuit of the plate bypass capacitor. What happened?What happened? A.It would short out the power supply A.It would short out the power supply B.It would remove the plate voltage B.It would remove the plate voltage C.It would possibly damage the power supply C.It would possibly damage the power supply D.All of the above D.All of the above

6A385 6A385DDA shunt-fed plate circuit of a vacuum tube amplifier has a short circuit of the plate RF choke. What A shunt-fed plate circuit of a vacuum tube amplifier has a short circuit of the plate RF choke. What happens?happens? A.The plate tank circuit would be effectively shorted A.The plate tank circuit would be effectively shorted B.The DC plate current would increase, possibly to excess B.The DC plate current would increase, possibly to excess C.No RF output could be expected C.No RF output could be expected D.All of the above D.All of the above

6A386 6A386AAThe total bandwidth of a transmitter using A-2 emission with a modulating frequency of 800 Hz and a The total bandwidth of a transmitter using A-2 emission with a modulating frequency of 800 Hz and a carrier frequency of 500 kHz is:carrier frequency of 500 kHz is: A.1600 Hz A.1600 Hz B.1.6 kHz B.1.6 kHz C.800 kHz C.800 kHz D.1000 kHz D.1000 kHz

6A387 6A387AAGiven a vacuum tube of the following characteristics: plate voltage 1000 V, plate current 127 ma, Given a vacuum tube of the following characteristics: plate voltage 1000 V, plate current 127 ma, filament current 5.4 amp, mutual conductance 8000 microvolts, and amplification factor of 25. What is filament current 5.4 amp, mutual conductance 8000 microvolts, and amplification factor of 25. What is the correct volume of negative grid bias for Class B amplifier?the correct volume of negative grid bias for Class B amplifier? A.40 V A.40 V B.50 V B.50 V C.30 V C.30 V D.60 V D.60 V

6A388 6A388AAWhen the relative amplitudes of the positive and negative modulation peaks are unsymmetrical:When the relative amplitudes of the positive and negative modulation peaks are unsymmetrical: A.Carrier shift A.Carrier shift B.Frequency shift B.Frequency shift C.Amplifier shift C.Amplifier shift D.None of the above D.None of the above

6A389 6A389

DDWhat may be used as indicating devices in neutralizing an RF amplifier stage?What may be used as indicating devices in neutralizing an RF amplifier stage? A.Neon bulb, sensitive wavemeter A.Neon bulb, sensitive wavemeter B.A flashlight bulb connected to a small loop of wire, a sensitive thermocoupler either attached to a B.A flashlight bulb connected to a small loop of wire, a sensitive thermocoupler either attached to a small loop of wiresmall loop of wire C.Amplifier grid current meter, a thermocouple meter connected in series with the plate tank C.Amplifier grid current meter, a thermocouple meter connected in series with the plate tank D.All of the above D.All of the above

6A390 6A390DDImportant factors in the operation of the vacuum tube as a frequency doubler are:Important factors in the operation of the vacuum tube as a frequency doubler are: A.Plate tank should be tuned to twice the grid circuit frequency A.Plate tank should be tuned to twice the grid circuit frequency B.The grid bias should be very large, the grid driving voltage must be very large, the plate voltage B.The grid bias should be very large, the grid driving voltage must be very large, the plate voltage should be comparatively highshould be comparatively high C.The plate tank circuit should have a low C to L ratio C.The plate tank circuit should have a low C to L ratio D.All of the above D.All of the above

6A391 6A391AAIf a 1500 kHz radio wave is modulated by a 2000 Hz sine wave tone, what frequencies does the If a 1500 kHz radio wave is modulated by a 2000 Hz sine wave tone, what frequencies does the modulated wave contain?modulated wave contain? A.1500 kHz , 1502 kHz , 1498 kHz A.1500 kHz , 1502 kHz , 1498 kHz B.1500 MHz , 1502 MHz , 1498 MHz B.1500 MHz , 1502 MHz , 1498 MHz C.1500 Hz , 1502 Hz , 1498 Hz C.1500 Hz , 1502 Hz , 1498 Hz D.None of the above D.None of the above 6A392 6A392AATo avoid damage to components what precautions should be observed in tuning a transmitter?To avoid damage to components what precautions should be observed in tuning a transmitter? A.It should be adjusted at reduced power A.It should be adjusted at reduced power B.It should be adjusted under normal power B.It should be adjusted under normal power C.Plate tank circuits are tuned for maximum DC current C.Plate tank circuits are tuned for maximum DC current D.None of the above D.None of the above

6A393 6A393AAA transmitter has a master-oscillator, intermediate amplifier, and final amplifier. In what order should A transmitter has a master-oscillator, intermediate amplifier, and final amplifier. In what order should the circuit be adjusted in putting the transmitter in operation?the circuit be adjusted in putting the transmitter in operation? A.Master-oscillator, intermediate amplifier, final amplifier, antenna circuit A.Master-oscillator, intermediate amplifier, final amplifier, antenna circuit B.Antenna circuit, master-oscillator, intermediate amplifier, final amplifier B.Antenna circuit, master-oscillator, intermediate amplifier, final amplifier C.Final amplifier, antenna circuit, master-oscillator, intermediate amplifier C.Final amplifier, antenna circuit, master-oscillator, intermediate amplifier D.Master-oscillator, intermediate amplifier, antenna circuit, final amplifier D.Master-oscillator, intermediate amplifier, antenna circuit, final amplifier

6A394 6A394DDExcessive plate current of an RF amplifier may be caused by:Excessive plate current of an RF amplifier may be caused by: A.Plate-tank circuit off resonance, defective tube A.Plate-tank circuit off resonance, defective tube B.Excessive loading of plate tank, insufficient bias, parasitic oscillations B.Excessive loading of plate tank, insufficient bias, parasitic oscillations

C.Excessive plate and screen voltage, excessive excitation voltage, improper neutralization C.Excessive plate and screen voltage, excessive excitation voltage, improper neutralization D.All of the above D.All of the above

6A395 6A395AAThe disadvantage of using a self-excited oscillator type of transmitter for shipboard service:The disadvantage of using a self-excited oscillator type of transmitter for shipboard service: A.Frequency instability A.Frequency instability B.Parasitic oscillations B.Parasitic oscillations C.Violent sound intensities C.Violent sound intensities D.Large capacity D.Large capacity

6A396 6A396AAThe degree of coupling is varied in a pi-network used to transfer energy from a vacuum tube plate circuit The degree of coupling is varied in a pi-network used to transfer energy from a vacuum tube plate circuit to an antenna:to an antenna: A.By adjusting the series capacitors A.By adjusting the series capacitors B.By adjusting the tank capacitors B.By adjusting the tank capacitors C.By changing the plate voltage C.By changing the plate voltage D.None of the above D.None of the above

6A397 6A397AAIn order of selectivity, the best receivers are:In order of selectivity, the best receivers are: A.Superheterodyne, tuned radio frequency, superregenerative A.Superheterodyne, tuned radio frequency, superregenerative B.Tuned radio-frequency, superheterodyne, superregenerative B.Tuned radio-frequency, superheterodyne, superregenerative C.Superregenerative, tuned radio-frequency, superheterodyne C.Superregenerative, tuned radio-frequency, superheterodyne D.Tuned radio frequency, superregenerative, superheterodyne D.Tuned radio frequency, superregenerative, superheterodyne

6A398 6A398AAAn RF filter in the plate circuit of a tube detector is sometimes necessary to:An RF filter in the plate circuit of a tube detector is sometimes necessary to: A.Prevent RF variations from affecting the following audio stages A.Prevent RF variations from affecting the following audio stages B.Alter the impedance of the detector load circuit B.Alter the impedance of the detector load circuit C.Insert RF variations from affecting the audio stages C.Insert RF variations from affecting the audio stages D.To prevent RF variations from affecting the following RF stages D.To prevent RF variations from affecting the following RF stages

6A399 6A399AAIn an RF amplifier with fixed bias, as the plate circuit is varied from below resonance to above In an RF amplifier with fixed bias, as the plate circuit is varied from below resonance to above resonance, what will the grid current do?resonance, what will the grid current do? A.The grid current will rise slightly at resonance A.The grid current will rise slightly at resonance B.The grid current will dip slightly at resonance B.The grid current will dip slightly at resonance C.The grid current will not vary C.The grid current will not vary

D.None of the above D.None of the above

6A400 6A400AAIn a self-biased RF amplifier stage: plate voltage is 1250 V, plate current 150 ma, grid current 15 ma, In a self-biased RF amplifier stage: plate voltage is 1250 V, plate current 150 ma, grid current 15 ma, grid-leak resistance of 4000 ohms, what is the operating grid bias?grid-leak resistance of 4000 ohms, what is the operating grid bias? A.60 V A.60 V B.30 V B.30 V C.90 V C.90 V D.50 V D.50 V

6A401 6A401AAHow would you determine the cathode bias resistance necessary to provide correct grid bias for an How would you determine the cathode bias resistance necessary to provide correct grid bias for an amplifier?amplifier? A.Bias is equal to IR drop across the cathode resistance A.Bias is equal to IR drop across the cathode resistance B.Measure with a regular multimeter B.Measure with a regular multimeter C.Both A & B C.Both A & B D.None of the above D.None of the above

6A402 6A402AAWhat is a method of link coupling between two R-F amplifier stages?What is a method of link coupling between two R-F amplifier stages? A.The coupling together of two circuits which may be separated by a relatively large distance with low- A.The coupling together of two circuits which may be separated by a relatively large distance with low-impedanceimpedance B.The coupling together of two circuits which may be separated by a relatively short distance B.The coupling together of two circuits which may be separated by a relatively short distance C.Isolating one R-F amplifier stage by using a closed loop coupler C.Isolating one R-F amplifier stage by using a closed loop coupler D.Either B or C D.Either B or C

6A403 6A403BBWhich type of amplifier circuit is used in a link coupling R-F?Which type of amplifier circuit is used in a link coupling R-F? A.Push-push A.Push-push B.Push-pull B.Push-pull C.Phase splitter C.Phase splitter D.FM discriminator D.FM discriminator

6A404 6A404CCAn advantage of link coupling between RF amplifier stages is:An advantage of link coupling between RF amplifier stages is: A.The flexibility of mechanical construction possible A.The flexibility of mechanical construction possible B.Reduction of tube capacitance effects on the L/C ratio of the tank circuits B.Reduction of tube capacitance effects on the L/C ratio of the tank circuits C.Both A and B C.Both A and B D.Neither A or B D.Neither A or B

6A405 6A405CCWhat effect does excessive coupling between the output circuit of an oscillator and an antenna have?What effect does excessive coupling between the output circuit of an oscillator and an antenna have? A.The effect of cross-modulation of nearby frequencies A.The effect of cross-modulation of nearby frequencies B.Instability of the oscillator and feedback op-amp B.Instability of the oscillator and feedback op-amp C.The oscillator will be very unstable C.The oscillator will be very unstable D.Frequency discrimination will be unstable D.Frequency discrimination will be unstable

6A406 6A406CCHow is power output of a transmitter adjusted?How is power output of a transmitter adjusted? A.It should radiate the minimum power necessary to insure reliable communications A.It should radiate the minimum power necessary to insure reliable communications B.It may be controlled by varying the plate supply B.It may be controlled by varying the plate supply C.Both A and B C.Both A and B D.None of the above D.None of the above

6A407 6A407AAWhen is a transmitter tuned to reduced power?When is a transmitter tuned to reduced power? A.The receiver is initially reduced because the receiver is very sensitive A.The receiver is initially reduced because the receiver is very sensitive B.The receiver is non adjustable in almost all applications B.The receiver is non adjustable in almost all applications C.The receiver has a pre-stage amplifier that self-adjusts C.The receiver has a pre-stage amplifier that self-adjusts D.In the doubler stages D.In the doubler stages

6A408 6A408DDWhat is meant by split tuning?What is meant by split tuning? A.An effect resulting from excessive coupling between two tuned circuits which are at the same A.An effect resulting from excessive coupling between two tuned circuits which are at the same frequencyfrequency B.Also known as double hump B.Also known as double hump C.Also known as critical coupling C.Also known as critical coupling D.Both A and B D.Both A and B

6A409 6A409CCWhat is a self rectified circuit?What is a self rectified circuit? A.Provides a tone frequency for F3F emissions A.Provides a tone frequency for F3F emissions B.An op-amp circuit that provides a feed-back to the input B.An op-amp circuit that provides a feed-back to the input C.Provides a tone frequency for A-2 emissions C.Provides a tone frequency for A-2 emissions D.A self oscillating frequency discriminator circuit D.A self oscillating frequency discriminator circuit

6A410 6A410AA

What would be the dB change in field intensity at a given distance if the power is doubled?What would be the dB change in field intensity at a given distance if the power is doubled? A.3 dB A.3 dB B.6 dB B.6 dB C.2 dB C.2 dB D.10 dB D.10 dB

6A411 6A411CCKeying can be accomplished at various points in a radiotelegraph transmitter. Some are:Keying can be accomplished at various points in a radiotelegraph transmitter. Some are: A.At the primary of power transformer, at filament centertap, at screen grid circuit A.At the primary of power transformer, at filament centertap, at screen grid circuit B.At the control grid circuit, at the DC supply B.At the control grid circuit, at the DC supply C.A or B C.A or B D.None of the above D.None of the above

6A412 6A412CCWhat is the term used when the receiving operator may interrupt the transmitting operator at any point What is the term used when the receiving operator may interrupt the transmitting operator at any point during transmission?during transmission? A.Modulation compandering A.Modulation compandering B.Interruption shift keying B.Interruption shift keying C.Break-in operation C.Break-in operation D.Transmission shift keying D.Transmission shift keying

6A413 6A413CCWhich of the following best explains frequency-shift keying?Which of the following best explains frequency-shift keying? A.The shifting of frequencies by modulating the carrier antenna A.The shifting of frequencies by modulating the carrier antenna B.Changing the frequency of the input when the key is depressed B.Changing the frequency of the input when the key is depressed C.Changing the frequency of the output when the key is depressed C.Changing the frequency of the output when the key is depressed D.None of the above D.None of the above

6A414 6A414CCWhat is one of the advantages frequency-shift keying has over "on-off" keying?What is one of the advantages frequency-shift keying has over "on-off" keying? A.Increase of transmitter bandwidth A.Increase of transmitter bandwidth B.Decrease of signal-to-noise ratio B.Decrease of signal-to-noise ratio C.Increase of signal-to-noise ratio C.Increase of signal-to-noise ratio D.Both A and C D.Both A and C

6A415 6A415AA

Code speed or number of words per minute transmitted have what effect if any on the bandwidth of Code speed or number of words per minute transmitted have what effect if any on the bandwidth of emission of a radiotelegraph transmitter?emission of a radiotelegraph transmitter? A.It does have an effect. Bandwidth increases as the code speed is increased A.It does have an effect. Bandwidth increases as the code speed is increased B.No effect. Bandwidth decreases as the code speed is increased B.No effect. Bandwidth decreases as the code speed is increased C.Signal strength increases as the speed increases C.Signal strength increases as the speed increases D.Both A & C D.Both A & C

6A416 6A416AAKeying a simple-oscillator type of emergency transmitter may be accomplished by:Keying a simple-oscillator type of emergency transmitter may be accomplished by: A.Inserting the key in series with the primary of the high voltage plate transformer A.Inserting the key in series with the primary of the high voltage plate transformer B.Inserting the key in parallel with the primary of the high voltage plate transformer B.Inserting the key in parallel with the primary of the high voltage plate transformer C.Inserting the key in series with the final output to the antenna C.Inserting the key in series with the final output to the antenna D.None of the above D.None of the above

6A417 6A417DDThe plate current of the final RF amplifier in a transmitter increases and radiation decreases, if the The plate current of the final RF amplifier in a transmitter increases and radiation decreases, if the antenna circuit is in good order, what could be the cause?antenna circuit is in good order, what could be the cause? A.Neutralization may have been upset A.Neutralization may have been upset B.The plate circuit may have been detuned, bias may have been lost B.The plate circuit may have been detuned, bias may have been lost C.Grid excitation may have decreased, there may be a faulty tube, or there may be parasitic oscillations C.Grid excitation may have decreased, there may be a faulty tube, or there may be parasitic oscillations D.All of the above D.All of the above

6A418 6A418CCWhen hoisting a shipboard antenna, to avoid damage to the wire and insulators:When hoisting a shipboard antenna, to avoid damage to the wire and insulators: A.Avoid bending the wire A.Avoid bending the wire B.Avoid smashing the insulators against metal objects B.Avoid smashing the insulators against metal objects C.A and B C.A and B D.None of the above D.None of the above

6A419 6A419AAIf a field strength is 100 microvolts per meter at 100 miles, what is the field strength at 200 miles?If a field strength is 100 microvolts per meter at 100 miles, what is the field strength at 200 miles? A.50 microvolts A.50 microvolts B.10 microvolts B.10 microvolts C.200 microvolts C.200 microvolts D.150 microvolts D.150 microvolts

6A420 6A420AAField intensity is:Field intensity is:

A.Directly proportional to the antenna current A.Directly proportional to the antenna current B.Inversely proportional to the antenna current B.Inversely proportional to the antenna current C.Directly proportional to the square of the antenna current C.Directly proportional to the square of the antenna current D.Directly proportional to the square root of the antenna current D.Directly proportional to the square root of the antenna current

6A421 6A421AAWhat point on a shipboard antenna system displays the maximum potential?What point on a shipboard antenna system displays the maximum potential? A.The end of the antenna furthest from the transmission line connections A.The end of the antenna furthest from the transmission line connections B.The end of the antenna closest to the transmission line connections B.The end of the antenna closest to the transmission line connections C.Near the center of the antenna C.Near the center of the antenna D.None of the above D.None of the above

6A4226A422DDA defective vacuum tube in a transmitter may be indicated by:A defective vacuum tube in a transmitter may be indicated by: A.Gas glow within the tube A.Gas glow within the tube B.No light from the filament B.No light from the filament C.Reduced output C.Reduced output D.All of the above D.All of the above

6A423 6A423CCA master-oscillator power-amplifier transmitter has been operating normally. The antenna ammeter A master-oscillator power-amplifier transmitter has been operating normally. The antenna ammeter suddenly reads zero. All filaments are burning and plate and grid meters read normal currents and suddenly reads zero. All filaments are burning and plate and grid meters read normal currents and voltages. What happened?voltages. What happened? A.A shorted antenna ammeter A.A shorted antenna ammeter B.An open connection in the remote reading meter B.An open connection in the remote reading meter C.Both a and b C.Both a and b D.None of the above D.None of the above

6A424 6A424DDEffects of dirty or salt-encrusted insulation are:Effects of dirty or salt-encrusted insulation are: A.Erratic readings of antenna current A.Erratic readings of antenna current B.Increased corona discharge B.Increased corona discharge C.Decreased radiation power C.Decreased radiation power D.All of the above D.All of the above

6A425 6A425AATo reduce the sparking at the contacts of a key used in a radiotelegraph transmitter:To reduce the sparking at the contacts of a key used in a radiotelegraph transmitter: A.Connect a suitable key-click filter across the key A.Connect a suitable key-click filter across the key

B.Connect a suitable key-click filter in series with the key B.Connect a suitable key-click filter in series with the key C.Connect a suitable high-pass filter across the key C.Connect a suitable high-pass filter across the key D.Increase the contact space of the key D.Increase the contact space of the key

6A426 6A426AAIn a self excited oscillator, a swinging antenna:In a self excited oscillator, a swinging antenna: A.Will cause serious frequency instability A.Will cause serious frequency instability B.Will cause no noticeable frequency instability B.Will cause no noticeable frequency instability C.May cause minor frequency instability C.May cause minor frequency instability D.None of the above D.None of the above

6A4276A427AAWhat may be observed as the antenna circuit is brought into resonance about the plate current of the final What may be observed as the antenna circuit is brought into resonance about the plate current of the final amplifier?amplifier? A.It will increase A.It will increase B.It will decrease B.It will decrease C.It will remain constant C.It will remain constant D.None of the above D.None of the above

6A428 6A428DDInstruments used to indicate various DC currents and voltages in a transmitter may be protected against Instruments used to indicate various DC currents and voltages in a transmitter may be protected against damage to stray RF by:damage to stray RF by: A.Insufficient grid blocking bias is applied to the grid when the key is open A.Insufficient grid blocking bias is applied to the grid when the key is open B.Shorted bias resistor B.Shorted bias resistor C.Shorted key-click filter C.Shorted key-click filter D.All of the above D.All of the above

6A429 6A429DDIn a radiotelegraph transmitter with a DC generator plate voltage source, an AC generator filament In a radiotelegraph transmitter with a DC generator plate voltage source, an AC generator filament supply, and grid-bias keying, what could be wrong when the emission continues with the key contacts supply, and grid-bias keying, what could be wrong when the emission continues with the key contacts open?open? A.Insufficient grid blocking bias is applied to the grid when the key is open A.Insufficient grid blocking bias is applied to the grid when the key is open B.Shorted bias resistor B.Shorted bias resistor C.Shorted key-click filter C.Shorted key-click filter D.All of the above D.All of the above

6A430 6A430AA

A station has an assigned frequency of 8000 kHz and a frequency tolerance of plus or minus 0.04%. The A station has an assigned frequency of 8000 kHz and a frequency tolerance of plus or minus 0.04%. The oscillator operates at 1/8th of the input. What is the maximum permitted deviation of the oscillation oscillator operates at 1/8th of the input. What is the maximum permitted deviation of the oscillation frequency in Hz, which will not exceed the tolerance?frequency in Hz, which will not exceed the tolerance? A.Plus or minus 400 Hz A.Plus or minus 400 Hz B.Plus or minus 320 Hz B.Plus or minus 320 Hz C.Plus or minus 800 Hz C.Plus or minus 800 Hz D.Plus or minus 640 Hz D.Plus or minus 640 Hz

6A431 6A431AAA transmitter operating on 5000 kHz uses a 1000 kHz crystal with a tempered coefficient of - 4 A transmitter operating on 5000 kHz uses a 1000 kHz crystal with a tempered coefficient of - 4 Hz/MHz/0 degrees centigrade. What is the change in the output frequency of the transmitter if the Hz/MHz/0 degrees centigrade. What is the change in the output frequency of the transmitter if the temperature increases 6 degrees centigrade?temperature increases 6 degrees centigrade? A.499.88 kHz A.499.88 kHz B.5000.12 kHz B.5000.12 kHz C.4120.0 kHz C.4120.0 kHz D.5120.0 kHz D.5120.0 kHz

6A432 6A432CCThe correct formula for determining the surge impedance of a quarter wavelength matching line is:The correct formula for determining the surge impedance of a quarter wavelength matching line is: A.Impedance total equal 0.25 over 1 squared A.Impedance total equal 0.25 over 1 squared B.Impedance total equal impedance of the antenna times impedance of the line squared over 1 times B.Impedance total equal impedance of the antenna times impedance of the line squared over 1 times C.14C.14 C.Impedance zero equal impedance of antenna times impedance of the line squared C.Impedance zero equal impedance of antenna times impedance of the line squared D.None of the above D.None of the above

6A433 6A433AAWhat are the three factors to consider when figuring the surge impedance of a non-resonant transmission What are the three factors to consider when figuring the surge impedance of a non-resonant transmission line?line? A.Diameter of the conductor, space between conductors, dielectric constant of insulating material A.Diameter of the conductor, space between conductors, dielectric constant of insulating material B.Voltage on RF line, diameter of conductors, space between dielectric B.Voltage on RF line, diameter of conductors, space between dielectric C.Diameter of shielding, space between dielectric constant, insulating shield around the conductor C.Diameter of shielding, space between dielectric constant, insulating shield around the conductor D.None of the above D.None of the above

6A434 6A434CCIf the output frequency after passing through three doubler stages is 16,800 kHz, give the crystal If the output frequency after passing through three doubler stages is 16,800 kHz, give the crystal frequency of a transmitter:frequency of a transmitter: A.2160 kHz A.2160 kHz B.2 GHz B.2 GHz C.2110 kHz C.2110 kHz D.2 kHz D.2 kHz

6A435 6A435

AAAdding an inductor in series with an antenna will have what effect on the resonant frequency?Adding an inductor in series with an antenna will have what effect on the resonant frequency? A.Decrease A.Decrease B.Increase B.Increase C.Neutralization C.Neutralization D.Equalization D.Equalization

6A436 6A436BBAdding a capacitor in series with an antenna will have what effect on resonant frequency?Adding a capacitor in series with an antenna will have what effect on resonant frequency? A.Decrease A.Decrease B.Increase B.Increase C.Neutralization C.Neutralization D.Equalization D.Equalization

6A437 6A437DDThe radiated wavelength of a Hertzian antenna is:The radiated wavelength of a Hertzian antenna is: A.1/2 the physical length of the modulated coaxial A.1/2 the physical length of the modulated coaxial B.1/4 the physical length of the modulated RF line B.1/4 the physical length of the modulated RF line C.1/2 the physical length of the antenna C.1/2 the physical length of the antenna D.Approximately twice the physical length of the antenna D.Approximately twice the physical length of the antenna

6A438 6A438BBTo operate on a lower resonant frequency on an available Marconi antenna which would be the correct To operate on a lower resonant frequency on an available Marconi antenna which would be the correct procedure?procedure? A.Add a capacitor in series with the antenna A.Add a capacitor in series with the antenna B.Add an inductor in series with the antenna B.Add an inductor in series with the antenna C.Add a screen grid bypass capacitor parallel to the antenna trap C.Add a screen grid bypass capacitor parallel to the antenna trap D.Add an RF choke across the feed line to ground D.Add an RF choke across the feed line to ground

6A439 6A439DDBy reducing the physical length of a Hertzian antenna what are the results?By reducing the physical length of a Hertzian antenna what are the results? A.The resonant frequency will be reduced A.The resonant frequency will be reduced B.The signal on a nearby frequency will be saturated upon modulation B.The signal on a nearby frequency will be saturated upon modulation C.The antenna trap is reduced causing cross modulation C.The antenna trap is reduced causing cross modulation D.The resonant frequency will increase D.The resonant frequency will increase

6A440 6A440DDWhich antenna system has the ability to discriminate between various directions of receiving or Which antenna system has the ability to discriminate between various directions of receiving or transmitting?transmitting? A.1/4 stub bi-directional A.1/4 stub bi-directional

B.Multi-band Marconi 1/2 wave B.Multi-band Marconi 1/2 wave C.1/2 wavelength Yagi perpendicular polarized antenna C.1/2 wavelength Yagi perpendicular polarized antenna D.Single element vertical antenna D.Single element vertical antenna

6A441 6A441BBGiven the current and resistance of the base of a Marconi antenna, what would be the formula for Given the current and resistance of the base of a Marconi antenna, what would be the formula for determining the power?determining the power? A.P = watts x amps A.P = watts x amps B.P = amps. squared x resistance B.P = amps. squared x resistance C.P = current x resistance C.P = current x resistance D.None of the above D.None of the above

6A442 6A442DDA vertical loop antenna has a:A vertical loop antenna has a: A.Omni-directional pattern which is maximum in the directions of the plane of the loop, and minimum A.Omni-directional pattern which is maximum in the directions of the plane of the loop, and minimum in the directions broadside to the loopin the directions broadside to the loop B.Non-directional with regard to compass points B.Non-directional with regard to compass points C.Has minimum radiation or reception in the direction of the ends of the antenna C.Has minimum radiation or reception in the direction of the ends of the antenna D.Has a bi-directional pattern which is maximum in the direction of the plane of the loop, and minimum D.Has a bi-directional pattern which is maximum in the direction of the plane of the loop, and minimum in the directions broadside to the loopin the directions broadside to the loop

6A443 6A443CCWhat modulation is contained in static and lightning radio waves?What modulation is contained in static and lightning radio waves? A.All odd harmonic frequencies A.All odd harmonic frequencies B.All even harmonic frequencies B.All even harmonic frequencies C.Amplitude modulation C.Amplitude modulation D.Frequency modulation D.Frequency modulation

6A444 6A444AAThe difference between a Hertz and Marconi antenna is:The difference between a Hertz and Marconi antenna is: A.The physical length A.The physical length B.The positioning of the capacitor feed traps B.The positioning of the capacitor feed traps C.The grounding of RF shielding C.The grounding of RF shielding D.None of the above D.None of the above

6A445 6A445CCWhat is meant by the term polarization of a radio wave?What is meant by the term polarization of a radio wave? A.Electromagnetic waves penetrate conductors because of eddy currents A.Electromagnetic waves penetrate conductors because of eddy currents B.Electromagnetically charged waves cross the zero axis in perpendicular patterns causing polarization B.Electromagnetically charged waves cross the zero axis in perpendicular patterns causing polarization to appearto appear

C.The polarization of a radio wave is determined by the direction of the electromagnetic wave plane C.The polarization of a radio wave is determined by the direction of the electromagnetic wave plane D.The polarization of a radio wave is determined by the direction of the magnetic wave plane D.The polarization of a radio wave is determined by the direction of the magnetic wave plane

6A446 6A446CCWhat are the lowest frequencies used in radio communication today?What are the lowest frequencies used in radio communication today? A.SSB voice A.SSB voice B.Double-sideband FM voice B.Double-sideband FM voice C.15 kHz C.15 kHz D.1 kHz to 5 kHz D.1 kHz to 5 kHz

6A447 6A447AARadio frequencies that are useful for long distance communications requiring continuous operation:Radio frequencies that are useful for long distance communications requiring continuous operation: A.Low frequency A.Low frequency B.High frequency B.High frequency C.Very high frequency C.Very high frequency D.Ultra high frequency D.Ultra high frequency

6A448 6A448CCCommunication at frequencies in the order of 15 kHz are usually accomplished by ground waves, and Communication at frequencies in the order of 15 kHz are usually accomplished by ground waves, and require generation of ____ power outputs for reliable and continuous operation:require generation of ____ power outputs for reliable and continuous operation: A.High power A.High power B.Low power B.Low power C.Extremely high power C.Extremely high power D.Extremely low power D.Extremely low power

6A449 6A449CCFrequencies with substantially line propagations:Frequencies with substantially line propagations: A.VHF, UHF, microwave A.VHF, UHF, microwave B.About 50-30,000 MHz B.About 50-30,000 MHz C.A & B C.A & B D.None of the above D.None of the above

6A450 6A450AAOn an average yearly basis the received Trans-Atlantic signals increased in strength in proportion to the On an average yearly basis the received Trans-Atlantic signals increased in strength in proportion to the degree of ____. Made on the basis of the 11 year cycle:degree of ____. Made on the basis of the 11 year cycle: A.Sun spot activity A.Sun spot activity B.Aurora borealis B.Aurora borealis C.Extratropical Advection C.Extratropical Advection D.Perigean tide D.Perigean tide

6A451 6A451DDHarmonic radiation is:Harmonic radiation is: A.Radiation occurring on frequencies that are whole multiples of the original frequency A.Radiation occurring on frequencies that are whole multiples of the original frequency B.Is always higher than the fundamental frequency B.Is always higher than the fundamental frequency C.Reduced by proper tuning of the transmitter C.Reduced by proper tuning of the transmitter D.All of the above D.All of the above

6A452 6A452CCHarmonic radiation from a transmitter may cause interference:Harmonic radiation from a transmitter may cause interference: A.Where the fundamental signal cannot be heard because of "skip" A.Where the fundamental signal cannot be heard because of "skip" B.In other shipboard equipment B.In other shipboard equipment C.A & B C.A & B D.None of the above D.None of the above

6A453 6A453CCWhy suppress RF harmonics in the output of a transmitter?Why suppress RF harmonics in the output of a transmitter? A.To prevent interference from occurring with other radio services A.To prevent interference from occurring with other radio services B.To restrict the bandwidth of the particular station to the legal limits B.To restrict the bandwidth of the particular station to the legal limits C.Both A & B C.Both A & B D.None of the above D.None of the above

6A454 6A454AAA wavetrap in a receiver:A wavetrap in a receiver: A.Prevents the effects of any undesired output of the receiver A.Prevents the effects of any undesired output of the receiver B.Generates desired frequencies in the output of the receiver B.Generates desired frequencies in the output of the receiver C.A & B C.A & B D.None of the above D.None of the above

6A455 6A455DDThe follow devices that could be used to indicate oscillation in a crystal oscillator are:The follow devices that could be used to indicate oscillation in a crystal oscillator are: A.Plate DC milliammeter, grid DC ammeter, neon bulb A.Plate DC milliammeter, grid DC ammeter, neon bulb B.Thermogalvanometer, wavemeter B.Thermogalvanometer, wavemeter C.Flashlight bulb on a loop of wire, heterodyne type frequency meter C.Flashlight bulb on a loop of wire, heterodyne type frequency meter D.All of the above D.All of the above

6A456 6A456DDAn artificial antenna sometimes used in testing a transmitter:An artificial antenna sometimes used in testing a transmitter: A.Dummy antenna A.Dummy antenna

B.Dummy load B.Dummy load C.Prevents undesired radiation C.Prevents undesired radiation D.All of the above D.All of the above

6A457 6A457DDThe system producing A-2 emission by a "chopper" may be thought of:The system producing A-2 emission by a "chopper" may be thought of: A.As a double-keying system A.As a double-keying system B.The automatic "chopper" turns the transmitter on and off at a rapid rate B.The automatic "chopper" turns the transmitter on and off at a rapid rate C.The other key is a normal hand operated key C.The other key is a normal hand operated key D.All of the above D.All of the above

6A458 6A458AAAdvantages of high-frequency radio communication:Advantages of high-frequency radio communication: A.The upper frequencies are substantially free of atmospheric interference, small antennas permit A.The upper frequencies are substantially free of atmospheric interference, small antennas permit efficient mobile operationefficient mobile operation B.Man-made noises are no problem, reflections may easily occur from buildings and other objects B.Man-made noises are no problem, reflections may easily occur from buildings and other objects C.A & B C.A & B D.None of the above D.None of the above

6A459 6A459DDTransmitters that employ variometers rather than variable capacitors as tuning elements do so because of:Transmitters that employ variometers rather than variable capacitors as tuning elements do so because of: A.The size of required variable capacitors in the medium frequency band A.The size of required variable capacitors in the medium frequency band B.There is no such thing as a variometer! B.There is no such thing as a variometer! C.Variometers can be relatively compact C.Variometers can be relatively compact D.A & C D.A & C

6A460 6A460BBThe relationship between the antenna current and radiated power of an antenna:The relationship between the antenna current and radiated power of an antenna: A.P=I2 X R A.P=I2 X R B.P=I2 X radiated resistance B.P=I2 X radiated resistance C.No relationship exists C.No relationship exists D.P=E x I D.P=E x I

6A461 6A461DDIron compound cylinders found in inductances:Iron compound cylinders found in inductances: A.Increase Q A.Increase Q B.Increase selectivity B.Increase selectivity C.Increase gain C.Increase gain

D.All of the above D.All of the above

6A462 6A462AAModulation of an RF carrier produces in the plate circuit of the last radio stage of the system:Modulation of an RF carrier produces in the plate circuit of the last radio stage of the system: A.High-level modulation A.High-level modulation B.Low-level modulation B.Low-level modulation C.Medium-level modulation C.Medium-level modulation D.None of the above D.None of the above

6A463 6A463DDBasically, am FM receiver is a conventional superheterodyne but differs in:Basically, am FM receiver is a conventional superheterodyne but differs in: A.The method of detection A.The method of detection B.The reduction of sensitivity to amplitude modulation B.The reduction of sensitivity to amplitude modulation C.De-emphasis C.De-emphasis D.All of the above D.All of the above

6A464 6A464AAA form of regenerative receiver in which the detector breaks into and out of oscillation at a rate above A form of regenerative receiver in which the detector breaks into and out of oscillation at a rate above audibility:audibility: A.Superregenerative receiver A.Superregenerative receiver B.Superheterodyne receiver B.Superheterodyne receiver C.Discriminator receiver C.Discriminator receiver D.Detuned radio frequency receiver D.Detuned radio frequency receiver

6A465 6A465DDA tuned RF amplifier stage ahead of the mixer stage in a superheterodyne receiver:A tuned RF amplifier stage ahead of the mixer stage in a superheterodyne receiver: A.Improves receiver sensitivity, improves image rejection A.Improves receiver sensitivity, improves image rejection B.Improves selectivity, improves stability B.Improves selectivity, improves stability C.Improves signal-to-noise ratio, reduced interference C.Improves signal-to-noise ratio, reduced interference D.All of the above D.All of the above

6A466 6A466AAWhat is the "mixer" tube in the superheterodyne receiver?What is the "mixer" tube in the superheterodyne receiver? A.The first detector A.The first detector B.The second detector B.The second detector C.The beat frequency oscillator C.The beat frequency oscillator D.None of the above D.None of the above

6A467 6A467AAAn incoming signal causing image interference is ____ the IF above or below the frequency to which the An incoming signal causing image interference is ____ the IF above or below the frequency to which the receiver is tuned:receiver is tuned: A.Twice A.Twice B.Three times B.Three times C.Half of C.Half of D.Three quarters of D.Three quarters of

6A468 6A468AAA superheterodyne receiver is adjusted to 2738 kHz. The IF is 475 kHz. What is the grid circuit of the A superheterodyne receiver is adjusted to 2738 kHz. The IF is 475 kHz. What is the grid circuit of the second detector tuned to?second detector tuned to? A.475 kHz A.475 kHz B.950 kHz B.950 kHz C.2263 kHz C.2263 kHz D.3213 kHz D.3213 kHz

6A469 6A469AAA superheterodyne receiver may not successfully be used for reception of frequencies very near the IF A superheterodyne receiver may not successfully be used for reception of frequencies very near the IF frequency:frequency: A.Because those near frequencies would pass directly through the IF amplifier and not be greatly A.Because those near frequencies would pass directly through the IF amplifier and not be greatly affected by the tuning of the RF or oscillator stagesaffected by the tuning of the RF or oscillator stages B.Because those near frequencies would not pass directly through the IF amplifier B.Because those near frequencies would not pass directly through the IF amplifier C.Because those near frequencies would be greatly affected by the tuning of the RF or oscillator stages C.Because those near frequencies would be greatly affected by the tuning of the RF or oscillator stages D.None of the above D.None of the above

6A470 6A470AASome superheterodyne receives employ a crystal-controlled oscillator:Some superheterodyne receives employ a crystal-controlled oscillator: A.To insure maximum stability of operation A.To insure maximum stability of operation B.To reduce noise generated by a conventional oscillator B.To reduce noise generated by a conventional oscillator C.Because it require no shielding C.Because it require no shielding D.To control feedback D.To control feedback

6A471 6A471DDTo obtain maximum response to weak CW signals with a superheterodyne receiver:To obtain maximum response to weak CW signals with a superheterodyne receiver: A.RF gain control should be fully advanced A.RF gain control should be fully advanced B.BFO control varied to obtain the clearest tone B.BFO control varied to obtain the clearest tone C.AVC advanced to the best volume C.AVC advanced to the best volume D.All of the above D.All of the above

6A472 6A472AAMost receiver hiss is due to:Most receiver hiss is due to: A.Noise generated in the first detector A.Noise generated in the first detector B.Noise generated in the first AF amplifier B.Noise generated in the first AF amplifier C.Faulty regeneration control C.Faulty regeneration control D.None of the above D.None of the above

6A473 6A473AAHigh IF frequencies in a superheterodyne receiver:High IF frequencies in a superheterodyne receiver: A.Reduce image frequency response A.Reduce image frequency response B.Increases image frequency response B.Increases image frequency response C.Places the image frequency as close as possible to the normal received frequency C.Places the image frequency as close as possible to the normal received frequency D.None of the above D.None of the above

6A474 6A474AAWhat is the IF of a superheterodyne receiver receiving on 1000 kHz and the mixing oscillator is tuned to What is the IF of a superheterodyne receiver receiving on 1000 kHz and the mixing oscillator is tuned to 1500 kHz?1500 kHz? A.500 kHz A.500 kHz B.2500 kHz B.2500 kHz C.2000 kHz C.2000 kHz D.None of the above D.None of the above

6A475 6A475DDImage response may be minimized in a superheterodyne receiver:Image response may be minimized in a superheterodyne receiver: A.By using one or more tuned RF stages ahead of the mixer A.By using one or more tuned RF stages ahead of the mixer B.By choosing a suitable IF (such that the image frequency will fall within the receiver's operating B.By choosing a suitable IF (such that the image frequency will fall within the receiver's operating range)range) C.By choosing a suitable IF (such that the image frequency will fall outside of the receiver's operating C.By choosing a suitable IF (such that the image frequency will fall outside of the receiver's operating range)range) D.A & C D.A & C

6A476 6A476DDIn a tuned RF receiver the heterodyne method, over the autodyne reception, has:In a tuned RF receiver the heterodyne method, over the autodyne reception, has: A.Great sensitivity A.Great sensitivity B.More stable operation of the circuit B.More stable operation of the circuit C.Wider control of the beat-frequency C.Wider control of the beat-frequency D.All of the above D.All of the above

6A477 6A477

DDA regenerative receiver's operation is:A regenerative receiver's operation is: A.An incoming RF carrier is coupled into the tuned-grid circuit and applied to the grid A.An incoming RF carrier is coupled into the tuned-grid circuit and applied to the grid B.It is then amplified in the usual manner. A controllable portion of the plate signal is coupled back into B.It is then amplified in the usual manner. A controllable portion of the plate signal is coupled back into the grid circuitthe grid circuit C.The coupled back signal is in phase with the original signal thus amplifying it and providing a greater C.The coupled back signal is in phase with the original signal thus amplifying it and providing a greater output signal in the plate circuitoutput signal in the plate circuit D.All of the above D.All of the above

6A478 6A478DDAdvantages of a stage of RF amplification are:Advantages of a stage of RF amplification are: A.Improved sensitivity, improved signal-to-noise ratio A.Improved sensitivity, improved signal-to-noise ratio B.Improved selectivity, improved signal-to-noise ratio B.Improved selectivity, improved signal-to-noise ratio C.Improved signal-to-noise ratio, more efficient and more stable operation of the detector C.Improved signal-to-noise ratio, more efficient and more stable operation of the detector D.All of the above D.All of the above

6A479 6A479DDDisadvantages of a stage of RF amplification are:Disadvantages of a stage of RF amplification are: A.A power audio amplifier would be needed to operate a loudspeaker A.A power audio amplifier would be needed to operate a loudspeaker B.An RF amplifier requires additional tuned circuits and tuning elements B.An RF amplifier requires additional tuned circuits and tuning elements C.Shielding will probably be necessary C.Shielding will probably be necessary D.All of the above D.All of the above

6A480 6A480AAThe sensitivity of a 3 circuit receiver is controlled by:The sensitivity of a 3 circuit receiver is controlled by: A.The setting of the regeneration control A.The setting of the regeneration control B.The setting of the audio frequency control B.The setting of the audio frequency control C.The setting of the radio frequency control C.The setting of the radio frequency control D.The setting of the beat frequency oscillator D.The setting of the beat frequency oscillator

6A481 6A481AAA regenerative, oscillating-detector receives directly coupled to an antenna:A regenerative, oscillating-detector receives directly coupled to an antenna: A.May radiate energy that can beat with other carrier frequencies and cause heterodyning interference in A.May radiate energy that can beat with other carrier frequencies and cause heterodyning interference in a number of receiversa number of receivers B.Cannot radiate energy B.Cannot radiate energy C.Radiates extremely high energy C.Radiates extremely high energy D.None of the above D.None of the above

6A482 6A482DDLow sensitivity of a 3 circuit regenerative receiver might be caused by:Low sensitivity of a 3 circuit regenerative receiver might be caused by:

A.Faulty tube A.Faulty tube B.Out of phase feedback B.Out of phase feedback C.Insufficient feedback C.Insufficient feedback D.All of the above D.All of the above

6A483 6A483DDSome components of a three-circuit regenerative circuit tested in troubleshooting:Some components of a three-circuit regenerative circuit tested in troubleshooting: A.All tubes, power supply voltage, continuity of coils A.All tubes, power supply voltage, continuity of coils B.Proper contacting of each position of tapped switches, pigtail connections, shorted variable capacitor B.Proper contacting of each position of tapped switches, pigtail connections, shorted variable capacitor C.Grid leak for open circuit, grid capacitor for short, audio transformer for continuity, jacks & cords, C.Grid leak for open circuit, grid capacitor for short, audio transformer for continuity, jacks & cords, antenna and ground connectionsantenna and ground connections D.All of the above D.All of the above

6A484 6A484DDNoisy operation of a regenerative, 3-circuit receiver with two stages of AF amplification may be caused Noisy operation of a regenerative, 3-circuit receiver with two stages of AF amplification may be caused by:by: A.Defective tubes, poor connections A.Defective tubes, poor connections B.Defective audio transformers B.Defective audio transformers C.Defective grid resistance of grid-capacitor, or defective elements in the power supply C.Defective grid resistance of grid-capacitor, or defective elements in the power supply D.All of the above D.All of the above

6A485 6A485CCHow could you test a regenerative receiver to determine if the detector is oscillating?How could you test a regenerative receiver to determine if the detector is oscillating? A.Touch a finger on grounded wire to the grid circuit. You will hear a "plop" if the circuit was A.Touch a finger on grounded wire to the grid circuit. You will hear a "plop" if the circuit was oscillatingoscillating B.Vary the regeneration control to its maximum limits. You will hear a "plop" as the circuit goes in and B.Vary the regeneration control to its maximum limits. You will hear a "plop" as the circuit goes in and out of oscillationout of oscillation C.Either A or B C.Either A or B D.None of the above D.None of the above

6A486 6A486AAHow would you adjust a regenerative receiver without RF amplifier stages to receive radiotelegraph How would you adjust a regenerative receiver without RF amplifier stages to receive radiotelegraph signals through interference?signals through interference? A.Provide the maximum selectivity and gain at the incoming signal frequency A.Provide the maximum selectivity and gain at the incoming signal frequency B.Increase the degree of coupling between the antenna and grid coils B.Increase the degree of coupling between the antenna and grid coils C.Provide the minimum possible regeneration C.Provide the minimum possible regeneration D.None of the above D.None of the above

6A487 6A487BBHow would you reduce or eliminate broadcast signal interference of reception on 500 kHz?How would you reduce or eliminate broadcast signal interference of reception on 500 kHz?

A.Use a regenerative receiver without RF amplifier stages A.Use a regenerative receiver without RF amplifier stages B.Use a suitable wavetrap resonated to reject the undesired signals B.Use a suitable wavetrap resonated to reject the undesired signals C.Use a crystal detector receiver tuned to the exact frequency C.Use a crystal detector receiver tuned to the exact frequency D.None of the above D.None of the above

6A488 6A488CCTo adjust a regenerative receiver for maximum sensitivity:To adjust a regenerative receiver for maximum sensitivity: A.The station is tuned in with the receiver in the oscillating condition A.The station is tuned in with the receiver in the oscillating condition B.Slowly back the regeneration control off until the receiver just breaks out of oscillation and is also B.Slowly back the regeneration control off until the receiver just breaks out of oscillation and is also below the fringe howl pointbelow the fringe howl point C.First A then B C.First A then B D.First B then A D.First B then A

6A489 6A489DDWhat type of radio receiver do not respond to static interference?What type of radio receiver do not respond to static interference? A.AM receivers are less responsive A.AM receivers are less responsive B.FM receivers have better sensitivity to such interference B.FM receivers have better sensitivity to such interference C.Both AM & FM C.Both AM & FM D.B & C D.B & C

6A490 6A490DDAudio howl may be caused by:Audio howl may be caused by: A.A "fringe" setting of the regeneration control A.A "fringe" setting of the regeneration control B.A defective tube B.A defective tube C.An open grid resistor C.An open grid resistor D.All of the above D.All of the above

6A491 6A491DDIf signals are heard with headphones in the detector plate circuit of a receiver, but none are heard with If signals are heard with headphones in the detector plate circuit of a receiver, but none are heard with headphones in the first AF stage plate circuit, what might be the cause?headphones in the first AF stage plate circuit, what might be the cause? A.Open winding of the coupling transformer A.Open winding of the coupling transformer B.Defective coupling capacitor, improper operating potentials B.Defective coupling capacitor, improper operating potentials C.Defective tube C.Defective tube D.All of the above D.All of the above

6A492 6A492CCIn the case of an open secondary winding in a coupling transformer causing no signal in the first AF In the case of an open secondary winding in a coupling transformer causing no signal in the first AF stage, satisfactory repair could be made by:stage, satisfactory repair could be made by: A.Replacing the transformer A.Replacing the transformer

B.Disconnecting the secondary winding and changing the coupling system to impedance coupling with a B.Disconnecting the secondary winding and changing the coupling system to impedance coupling with a grid resistor and coupling capacitorgrid resistor and coupling capacitor C.A & B C.A & B D.None of the above D.None of the above

6A493 6A493AAAn oscillator in a receiver operating on a frequency near the IF of the receiver:An oscillator in a receiver operating on a frequency near the IF of the receiver: A.Beats with the IF in the second detector to produce an audible note A.Beats with the IF in the second detector to produce an audible note B.May cause audio howl in the receiver B.May cause audio howl in the receiver C.Increases sensitivity C.Increases sensitivity D.May cause noisy operation of the receiver D.May cause noisy operation of the receiver

6A494 6A494AAGenerally used to prevent any undesired frequencies from appearing in the output of a receiver:Generally used to prevent any undesired frequencies from appearing in the output of a receiver: A.Wave trap A.Wave trap B.Wave guide B.Wave guide C.Ripple filter C.Ripple filter D.Tarody screen D.Tarody screen

6A495 6A495CCBy-pass capacitors across the cathode-bias resistors of an RF amplifier:By-pass capacitors across the cathode-bias resistors of an RF amplifier: A.Prevent variations of bias during excitation of the amplifier A.Prevent variations of bias during excitation of the amplifier B.Results in better gain of the amplifier stage B.Results in better gain of the amplifier stage C.A & B C.A & B D.None of the above D.None of the above

6A496 6A496DDIn general, shielding between RF amplifier stages:In general, shielding between RF amplifier stages: A.Prevents electromagnetic coupling A.Prevents electromagnetic coupling B.Prevents electrostatic coupling B.Prevents electrostatic coupling C.Improves the overall stability of a receiver C.Improves the overall stability of a receiver D.All of the above D.All of the above

6A497 6A497DDMinimizes transfer of harmonic frequencies between two inductively coupled circuits:Minimizes transfer of harmonic frequencies between two inductively coupled circuits: A.***<This answer left blank by the FCC> A.***<This answer left blank by the FCC> B.Induces magnetic shielding between two coils B.Induces magnetic shielding between two coils C.Transfers energy between two coils C.Transfers energy between two coils D.None of the above D.None of the above

6A498 6A498BBAn auxiliary receiving antenna on a ship with a radio direction finder:An auxiliary receiving antenna on a ship with a radio direction finder: A.Is mainly a spare antenna A.Is mainly a spare antenna B.Enables the radio operator to maintain watch on 500 kHz whether or not the direction finder is in use B.Enables the radio operator to maintain watch on 500 kHz whether or not the direction finder is in use C.Enables the radio operator to use the direction finder whether or not the communications receiver is in C.Enables the radio operator to use the direction finder whether or not the communications receiver is in useuse D.None of the above D.None of the above

6A499 6A499BBFeeding back into the control grids of the IF and RF amplifiers a negative DC bias which is proportioned Feeding back into the control grids of the IF and RF amplifiers a negative DC bias which is proportioned to the average magnitude of the received carrier wave accomplished:to the average magnitude of the received carrier wave accomplished: A.Rhymed effect A.Rhymed effect B.Automatic volume control B.Automatic volume control C.Neutralization C.Neutralization D.Refraction D.Refraction

6A500 6A500CCThe center-tap connection in a filament supply transformer:The center-tap connection in a filament supply transformer: A.Prevents hum voltages from modulating the normal signal A.Prevents hum voltages from modulating the normal signal B.The voltage change on one side of the filament will be effectively cancelled out by an equal and B.The voltage change on one side of the filament will be effectively cancelled out by an equal and opposite voltage change at the other side of the filament, yielding no humopposite voltage change at the other side of the filament, yielding no hum C.A & B C.A & B D.None of the above D.None of the above

6A501 6A501DDA shorted grid capacitor in a three-circuit regenerative receiver would:A shorted grid capacitor in a three-circuit regenerative receiver would: A.Render the receiver mostly or completely inoperative A.Render the receiver mostly or completely inoperative B.Have no noticeable effect B.Have no noticeable effect C.Some forms of plate detection might occur but with considerably reduced sensitivity and volume C.Some forms of plate detection might occur but with considerably reduced sensitivity and volume D.A & C D.A & C

6A502 6A502CCThe first detector in a superheterodyne receiver:The first detector in a superheterodyne receiver: A.Acts as a mixer, providing the action which produces the desired intermediate frequency A.Acts as a mixer, providing the action which produces the desired intermediate frequency B.The first detector must be operated on the non linear portion of its characteristic to provide the proper B.The first detector must be operated on the non linear portion of its characteristic to provide the proper actionaction C.A & B C.A & B D.None of the above D.None of the above

6A503 6A503DDThe advantage of using iron cores of special construction in RF transformers and inductance?The advantage of using iron cores of special construction in RF transformers and inductance? A.Increase of Q and gain of circuits using such cores A.Increase of Q and gain of circuits using such cores B.Increase of selectivity and gain of circuits using such cores B.Increase of selectivity and gain of circuits using such cores C.Increase of Q and selectivity C.Increase of Q and selectivity D.All of the above D.All of the above

6A504 6A504AAThe auto alarm receiver is tuned to ____ but is able to respond to signals from ____ to ____ (+/- 12.5 The auto alarm receiver is tuned to ____ but is able to respond to signals from ____ to ____ (+/- 12.5 kHz)kHz) A.500 kHz, 487.5 kHz, 512.5 kHz A.500 kHz, 487.5 kHz, 512.5 kHz B.500 kHz, 485.0 kHz, 515 kHz B.500 kHz, 485.0 kHz, 515 kHz C.500 kHz, 490.00 kHz, 510 kHz C.500 kHz, 490.00 kHz, 510 kHz D.500 kHz, 470.00 kHz, 530 kHz D.500 kHz, 470.00 kHz, 530 kHz

6A505 6A505AAThe auto-alarm signal is:The auto-alarm signal is: A.Four consecutive dashes from C.5 to D.5 seconds, separated by spaces ranging from 0.1 to 0.5 A.Four consecutive dashes from C.5 to D.5 seconds, separated by spaces ranging from 0.1 to 0.5 seconds. The combination may not exceed 5 secondsseconds. The combination may not exceed 5 seconds B.Three consecutive dashes from D.5 to 5.5 seconds, separated by spaces ranging from 0.5 to A.0 B.Three consecutive dashes from D.5 to 5.5 seconds, separated by spaces ranging from 0.5 to A.0 secondsseconds C.Five consecutive dashes from B.5-3.5 seconds, separated by spaces ranging from 0.01 to 0.25 seconds. C.Five consecutive dashes from B.5-3.5 seconds, separated by spaces ranging from 0.01 to 0.25 seconds. The combination may not exceed 5 secondsThe combination may not exceed 5 seconds D.None of the above D.None of the above

6A506 6A506DDThe determining factor of the setting of the sensitivity control of an auto-alarm receiver:The determining factor of the setting of the sensitivity control of an auto-alarm receiver: A.Prevailing static at a given time A.Prevailing static at a given time B.Radio interference at a given time B.Radio interference at a given time C.Signal strength C.Signal strength D.A & B D.A & B

6A507 6A507DDWith an auto alarm that uses a square-law detector and a mechanical selector what causes the bell to ring?With an auto alarm that uses a square-law detector and a mechanical selector what causes the bell to ring? A.Receipt of the true auto-alarm signal, low battery voltage A.Receipt of the true auto-alarm signal, low battery voltage B.Filament circuit open, the 24 V circuit to receiver open B.Filament circuit open, the 24 V circuit to receiver open C.Battery charger fuse blown, motor stopped or running C.Battery charger fuse blown, motor stopped or running D.All of the above D.All of the above

6A508 6A508

DDIntermittent ringing of the bells of an auto alarm with a linear detector and an electronic selector could beIntermittent ringing of the bells of an auto alarm with a linear detector and an electronic selector could be caused by:caused by: A.An intermittent vacuum tube filament A.An intermittent vacuum tube filament B.Fluctuating line voltage B.Fluctuating line voltage C.Faulty contacts or relay adjustment of warning relay receiver C.Faulty contacts or relay adjustment of warning relay receiver D.All of the above D.All of the above

6A509 6A509DDAn open filament on an auto-alarm with a linear detector and an electronic selector will:An open filament on an auto-alarm with a linear detector and an electronic selector will: A.De-energize the restore relay K-105 A.De-energize the restore relay K-105 B.K105 applies voltage to K-100, time delay relay B.K105 applies voltage to K-100, time delay relay C.K106 causes the bell to ring after about 2 minutes C.K106 causes the bell to ring after about 2 minutes D.All of the above D.All of the above

6A510 6A510CCThe auto-alarm bell rings and the release button stops it:The auto-alarm bell rings and the release button stops it: A.There could be reception of a true alarm signal A.There could be reception of a true alarm signal B.There could be reception of a false alarm signal B.There could be reception of a false alarm signal C.A or B C.A or B D.Neither A or B D.Neither A or B

6A511 6A511DDIf the auto-alarm bell rings and the release button doesn't stop it:If the auto-alarm bell rings and the release button doesn't stop it: A.Bell relay K-107 could be stuck, or there could be an open filament A.Bell relay K-107 could be stuck, or there could be an open filament B.The alarm bell relay circuit ground could be bad B.The alarm bell relay circuit ground could be bad C.There could be failure or low line voltage C.There could be failure or low line voltage D.All of the above D.All of the above

6A512 6A512AAIf the vacuum tube heater in an approved auto-alarm system burns out:If the vacuum tube heater in an approved auto-alarm system burns out: A.A pair of contacts close and energize the bell relay A.A pair of contacts close and energize the bell relay B.A pair on contacts open and energize the ball relay B.A pair on contacts open and energize the ball relay C.A pair of contacts close and de-energize the bell relay C.A pair of contacts close and de-energize the bell relay D.A pair of contacts open and deenergize the bell relay D.A pair of contacts open and deenergize the bell relay

6A513 6A513AAUnused portions of inductances in receivers are ____ to reduce any losses that might occur in these Unused portions of inductances in receivers are ____ to reduce any losses that might occur in these unused windings:unused windings:

A.Shorted A.Shorted B.Removed from the circuit B.Removed from the circuit C.Insulated C.Insulated D.Straightened out D.Straightened out

6A514 6A514DDHarmonic radiation by a transmitter may be prevented:Harmonic radiation by a transmitter may be prevented: A.By using a suitable crystal filter A.By using a suitable crystal filter B.By using a Faraday shield between the final amplifier and antenna circuit B.By using a Faraday shield between the final amplifier and antenna circuit C.By using suitable tuned filters in the transmission line system C.By using suitable tuned filters in the transmission line system D.B & C D.B & C

6A515 6A515AAThe keying circuit of the ships transmitter is disconnected:The keying circuit of the ships transmitter is disconnected: A.When the auto-alarm antenna switch is placed in the auto-alarm operating position A.When the auto-alarm antenna switch is placed in the auto-alarm operating position B.When the auto-alarm antenna switch is placed in the auto-alarm off position B.When the auto-alarm antenna switch is placed in the auto-alarm off position C.Manually as desired C.Manually as desired D.None of the above D.None of the above

6A516 6A516AANormal undistorted modulation is indicated by:Normal undistorted modulation is indicated by: A.An increase in antenna current without carrier shift A.An increase in antenna current without carrier shift B.A decrease in antenna current without carrier shift B.A decrease in antenna current without carrier shift C.An increase in antenna current with carrier shift C.An increase in antenna current with carrier shift D.A decrease in antenna current with carrier shift D.A decrease in antenna current with carrier shift

6A517 6A517CCIf a vacuum tube in the only RF stages of your receiver burned out, make a temporary repair by:If a vacuum tube in the only RF stages of your receiver burned out, make a temporary repair by: A.Remove its tube and connect a small (about 0.001 microfarad) capacitor between the control grid and A.Remove its tube and connect a small (about 0.001 microfarad) capacitor between the control grid and plate connectionsplate connections B.Connect the antenna to the control grid of the stage following the one which was burned out B.Connect the antenna to the control grid of the stage following the one which was burned out C.Either A or B C.Either A or B D.A & B D.A & B

6A518 6A518AAA ____ provides a very high degree of selectivity in a receiver:A ____ provides a very high degree of selectivity in a receiver: A.Crystal filter A.Crystal filter B.Low pass filter B.Low pass filter

C.Bleeder resistor C.Bleeder resistor D.By-pass capacitor D.By-pass capacitor

6A519 6A519CCThe D'Arsonval type meter consists of:The D'Arsonval type meter consists of: A.A permanent magnet, a movable coil with pointer attached rotating in jewel bearing A.A permanent magnet, a movable coil with pointer attached rotating in jewel bearing B.A movable coil with pointer attached rotating in jewel bearings, and two spiral springs (one on each B.A movable coil with pointer attached rotating in jewel bearings, and two spiral springs (one on each side of the removable coil)side of the removable coil) C.A & B C.A & B D.None of the above D.None of the above

6A520 6A520BBWhat is the purpose of multiplier resistance used with a voltmeter?What is the purpose of multiplier resistance used with a voltmeter? A.Multiplier resistance is not used with a voltmeter A.Multiplier resistance is not used with a voltmeter B.To increase the voltage indicating range of the voltmeter B.To increase the voltage indicating range of the voltmeter C.To decrease the voltage indicating range of the voltmeter C.To decrease the voltage indicating range of the voltmeter D.None of the above D.None of the above

6A521 6A521BBWhat is the purpose of a shunt as used with an ammeter?What is the purpose of a shunt as used with an ammeter? A.To permit a decrease in the indicating range of the meter A.To permit a decrease in the indicating range of the meter B.To permit an increase in the indicating range of the meter which is almost inversely proportional to the B.To permit an increase in the indicating range of the meter which is almost inversely proportional to the resistance of the shuntresistance of the shunt C.A shunt should not be used with a ammeter C.A shunt should not be used with a ammeter D.None of the above D.None of the above

6A522 6A522DDWhat is indicated if a voltmeter connected between the negative side of a ship's DC line and ground readsWhat is indicated if a voltmeter connected between the negative side of a ship's DC line and ground reads the full line voltage?the full line voltage? A.It indicates that the voltmeter leads are reversed A.It indicates that the voltmeter leads are reversed B.This indicates that the positive side of the line, rather then the negative side is grounded B.This indicates that the positive side of the line, rather then the negative side is grounded C.The generator terminals should be reversed C.The generator terminals should be reversed D.Both B & C are correct D.Both B & C are correct

6A523 6A523CCWhy are copper oxide rectifiers, associated with DC voltmeters to measure AC, unsuitable for the Why are copper oxide rectifiers, associated with DC voltmeters to measure AC, unsuitable for the measurement of voltages at radio frequencies?measurement of voltages at radio frequencies? A.Because of the relatively low shunt capacitance of the copper oxide rectifier A.Because of the relatively low shunt capacitance of the copper oxide rectifier B.The AC & DC voltages will read low B.The AC & DC voltages will read low C.Because of the relatively large shunt capacitance of the copper oxide rectifier C.Because of the relatively large shunt capacitance of the copper oxide rectifier

D.All of the above D.All of the above

6A524 6A524CCHow may the power in a AC circuit be determined?How may the power in a AC circuit be determined? A.The power in an AC circuit may be determined by a wattmeter A.The power in an AC circuit may be determined by a wattmeter B.By multiplying the product of the circuit voltage and current by the power factor B.By multiplying the product of the circuit voltage and current by the power factor C.Both answers A & B C.Both answers A & B D.None of the above D.None of the above

6A525 6A525BBThe product of the readings of an AC voltmeter and ammeter in an AC circuit is called what?The product of the readings of an AC voltmeter and ammeter in an AC circuit is called what? A.Reverse power A.Reverse power B.Apparent power B.Apparent power C.Current power C.Current power D.None of the above D.None of the above

6A526 6A526BBDoes an AC ammeter indicate peak, average, or effective values of current?Does an AC ammeter indicate peak, average, or effective values of current? A.The conventional AC ammeter is calibrated to indicate effective (TRM) values of current A.The conventional AC ammeter is calibrated to indicate effective (TRM) values of current B.The conventional AC ammeter is calibrated to indicate effective (RMS) values of current B.The conventional AC ammeter is calibrated to indicate effective (RMS) values of current C.An AC ammeter indicates peak values of current C.An AC ammeter indicates peak values of current D.An AC ammeter indicates average values of current D.An AC ammeter indicates average values of current

6A527 6A527CCWhat types of meters may be used to measure RF currents?What types of meters may be used to measure RF currents? A.The hot wire ammeter A.The hot wire ammeter B.The thermocouple ammeter B.The thermocouple ammeter C.Both A & B C.Both A & B D.None of the above D.None of the above

6A528 6A528CCHow may the range of a thermocouple ammeter be increased?How may the range of a thermocouple ammeter be increased? A.By using a current transformer A.By using a current transformer B.By using a capacitor shunt B.By using a capacitor shunt C.Both A & B C.Both A & B D.By using a resistor shunt D.By using a resistor shunt

6A529 6A529AA

By what factor must the voltage of an ac circuit, as indicated on the scale of an AC voltmeter, be By what factor must the voltage of an ac circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the average voltage value?multiplied to obtain the average voltage value? A.By the factor of 0.9 A.By the factor of 0.9 B.By the factor of 9.0 B.By the factor of 9.0 C.By the factor of A.0 C.By the factor of A.0 D.By the factor of B.0 D.By the factor of B.0

6A530 6A530BBBy what factor must the voltage of an AC circuit, as indicated on the scale of an AC voltmeter, be By what factor must the voltage of an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the peak value?multiplied to obtain the peak value? A.The multiplying factor is .414 A.The multiplying factor is .414 B.The multiplying factor is A.414 B.The multiplying factor is A.414 C.The multiplying factor is A.114 C.The multiplying factor is A.114 D.The multiplying factor is A.141 D.The multiplying factor is A.141

6A531 6A531AAWhat is the meaning of "zero beat" as used in connection with frequency measuring equipment?What is the meaning of "zero beat" as used in connection with frequency measuring equipment? A.Zero beat occurs when two frequencies are being mixed together and have no difference frequency A.Zero beat occurs when two frequencies are being mixed together and have no difference frequency between thembetween them B.To achieve this the frequencies must be suppressed B.To achieve this the frequencies must be suppressed C.The transmitter must be nulled C.The transmitter must be nulled D.None of the above D.None of the above

6A532 6A532DDWhat is the directional reception pattern of a loop antenna?What is the directional reception pattern of a loop antenna? A.A vertical loop antenna has a bidirectional pattern which is maximum in the directions in the plane of A.A vertical loop antenna has a bidirectional pattern which is maximum in the directions in the plane of the loop, and minimum in the directions broadside to the loopthe loop, and minimum in the directions broadside to the loop B.A horizontal loop antenna is nondirectional along the plane of the loop. It has minimum radiation or B.A horizontal loop antenna is nondirectional along the plane of the loop. It has minimum radiation or reception verticallyreception vertically C.A horizontal loop antenna is directional along the plane of the loop antenna C.A horizontal loop antenna is directional along the plane of the loop antenna D.Both A & B D.Both A & B

6A533 6A533AAWhat is the reception pattern of a vertical antenna?What is the reception pattern of a vertical antenna? A.It has minimum radiation or reception vertically A.It has minimum radiation or reception vertically B.A vertical Jackson antenna has a pattern which is nondirectional with regard to all compass points B.A vertical Jackson antenna has a pattern which is nondirectional with regard to all compass points C.It has maximum radiation or reception vertically C.It has maximum radiation or reception vertically D.None of the above D.None of the above

6A534 6A534AA

What is the principal function of a vertical sense antenna associated with a unilateral radio direction What is the principal function of a vertical sense antenna associated with a unilateral radio direction finder?finder? A.To determine from which direction the signal is coming A.To determine from which direction the signal is coming B.A vertical sense antenna is not associated with a radio direction finder B.A vertical sense antenna is not associated with a radio direction finder C.Unilateral radio direction finders are associated with loop antennas C.Unilateral radio direction finders are associated with loop antennas D.None of the above D.None of the above

6A535 6A535DDWhat figure represents the reception pattern of a properly adjusted unilateral radio direction finder?What figure represents the reception pattern of a properly adjusted unilateral radio direction finder? A.A cardioid A.A cardioid B.A figure eight B.A figure eight C.A heart shaped figure C.A heart shaped figure D.Both A & C D.Both A & C

6A536 6A536CCFrom how many simultaneous directions is a direction finder capable of receiving signals if adjusted to From how many simultaneous directions is a direction finder capable of receiving signals if adjusted to take unilateral bearings through 360 degrees?take unilateral bearings through 360 degrees? A.From 360 degrees A.From 360 degrees B.From 180 degrees B.From 180 degrees C.From all but one direction C.From all but one direction D.None of the above D.None of the above

6A537 6A537DDHow is the unilateral effect obtained in a direction finder?How is the unilateral effect obtained in a direction finder? A.With a balancing capacitor A.With a balancing capacitor B.With a compensator B.With a compensator C.With insulating material C.With insulating material D.None of the above D.None of the above

6A538 6A538CCWhat is the function of the balancing capacitor in a direction finder?What is the function of the balancing capacitor in a direction finder? A.To maximize "antenna effect" and so obtain a sharper null point indication of direction A.To maximize "antenna effect" and so obtain a sharper null point indication of direction B.To reduce the noise factor in the first IF B.To reduce the noise factor in the first IF C.To minimize "antenna effect" and so obtain a sharper null point indication of direction C.To minimize "antenna effect" and so obtain a sharper null point indication of direction D.None of the above D.None of the above

6A539 6A539BBWhat is indicated by the bearing obtained from the use of a bilateral radio direction finder?What is indicated by the bearing obtained from the use of a bilateral radio direction finder? A.A line of direction which passes through two stations A.A line of direction which passes through two stations B.A line of direction which passes through the originating station B.A line of direction which passes through the originating station

C.A line of direction can read in either direction C.A line of direction can read in either direction D.None of the above D.None of the above

6A540 6A540CCOn shipboard what factors may effect the accuracy of a direction finder after it has been properly On shipboard what factors may effect the accuracy of a direction finder after it has been properly installed, calibrated?installed, calibrated? A.A received wave which has been bent by night effect A.A received wave which has been bent by night effect B.By any changing of the position of nearby metallic objects B.By any changing of the position of nearby metallic objects C.Both A & B C.Both A & B D.None of the above D.None of the above

6A541 6A541BBWhat is indicated by the bearing obtained from the use of a unilateral radio direction finder?What is indicated by the bearing obtained from the use of a unilateral radio direction finder? A.The direction of another station A.The direction of another station B.The sense of direction of the originating station B.The sense of direction of the originating station C.All bearings are from C.All bearings are from D.None of the above D.None of the above

6A542 6A542CCWithin what frequency band limits do all United States marine radio beacon stations operate?Within what frequency band limits do all United States marine radio beacon stations operate? A.From 280 to 385 kHz A.From 280 to 385 kHz B.From 162 to 385 kHz B.From 162 to 385 kHz C.From 285 to 315 kHz C.From 285 to 315 kHz D.From 300 to 465 kHz D.From 300 to 465 kHz

6A543 6A543CCIn what part of the RF spectrum do marine radar systems operate?In what part of the RF spectrum do marine radar systems operate? A.In the order of 10,000 MHz or 3000 MHz A.In the order of 10,000 MHz or 3000 MHz B.Wavelength of 3 cm or 10 cm B.Wavelength of 3 cm or 10 cm C.Both A & B C.Both A & B D.None of the above D.None of the above

6A544 6A544BBApproximately at what speed does the antenna of a navigational radar rotate?Approximately at what speed does the antenna of a navigational radar rotate? A.At speeds ranging from about 6 to 19 RPM A.At speeds ranging from about 6 to 19 RPM B.At speeds ranging from about 6 to 15 RPM B.At speeds ranging from about 6 to 15 RPM C.At speeds ranging from about 15 to 30 RPM C.At speeds ranging from about 15 to 30 RPM D.At speeds ranging from about 20 to 40 RPM D.At speeds ranging from about 20 to 40 RPM

6A545 6A545CCHow should a radar set be adjusted by the operator to reduce "sea return"?How should a radar set be adjusted by the operator to reduce "sea return"? A.Rotate the antenna for a deep null A.Rotate the antenna for a deep null B.Reduce the gain control B.Reduce the gain control C.The operator should manually adjust the "suppressor" control or sensitivity time control, STC C.The operator should manually adjust the "suppressor" control or sensitivity time control, STC D.None of the above D.None of the above

6A546 6A546DDIn determining a "fix" position by a marine LORAN system, what is the minimum number of land In determining a "fix" position by a marine LORAN system, what is the minimum number of land transmitters involved?transmitters involved? A.A master & a slave station A.A master & a slave station B.1 slave station B.1 slave station C.2 slave stations & 1 master station C.2 slave stations & 1 master station D.Four, or two pairs of "master and "slave" stations D.Four, or two pairs of "master and "slave" stations

6A547 6A547AAWhat is the relationship between a master and a slave station in reference to LORAN navigation systems?What is the relationship between a master and a slave station in reference to LORAN navigation systems? A.A master station originates the RF pulse which then travels in all directions and is intercepted by the A.A master station originates the RF pulse which then travels in all directions and is intercepted by the slave stationslave station B.The slave station originates the RF pulse B.The slave station originates the RF pulse C.There must be at least two slave stations C.There must be at least two slave stations D.All of the above D.All of the above

6A548 6A548DDHow can the operator of a LORAN receiver on shipboard identify the transmitting stations that are being How can the operator of a LORAN receiver on shipboard identify the transmitting stations that are being received?received? A.By their pulse recurrence rate A.By their pulse recurrence rate B.By reference to their frequency of transmission B.By reference to their frequency of transmission C.None of the above C.None of the above D.Both A & B D.Both A & B

6A549 6A549AADuring daytime hours, approximately what is the maximum distance in nautical miles from LORAN During daytime hours, approximately what is the maximum distance in nautical miles from LORAN transmitting stations from which LORAN lines of position can be determined?transmitting stations from which LORAN lines of position can be determined? A.About 700 miles A.About 700 miles B.During nighttime hours, the maximum distance is increased to about 1800 miles by the use of sky B.During nighttime hours, the maximum distance is increased to about 1800 miles by the use of sky waveswaves

C.About 1000 miles C.About 1000 miles D.About 1500 miles D.About 1500 miles

6A550 6A550AAWhat is the purpose of blinking in a loran navigational system?What is the purpose of blinking in a loran navigational system? A.To warn the receiving operator that difficulty exists at the transmitting stations? A.To warn the receiving operator that difficulty exists at the transmitting stations? B.To warn the operator that the system is in use B.To warn the operator that the system is in use C.The loran system needs to be aligned C.The loran system needs to be aligned D.None of the above D.None of the above

6A551 6A551DDWhat precautions should an operator or serviceman observe when working with cathode-ray tubes?What precautions should an operator or serviceman observe when working with cathode-ray tubes? A.The tube must not strike against any hard surface A.The tube must not strike against any hard surface B.The tube might implode B.The tube might implode C.Safety goggles and gloves should be worn when handling cathode-ray tubes C.Safety goggles and gloves should be worn when handling cathode-ray tubes D.All of the above D.All of the above

6A552 6A552AAIf the velocity of a radio wave is 186,000 statute miles per second, how many nautical miles does a radar If the velocity of a radio wave is 186,000 statute miles per second, how many nautical miles does a radar pulse travel in one microsecond?pulse travel in one microsecond? A.0.1614 nautical miles A.0.1614 nautical miles B.11614 nautical miles B.11614 nautical miles C.0.2014 nautical miles C.0.2014 nautical miles D.2200 nautical miles D.2200 nautical miles

6A553 6A553CCIn all cases other than those in which the transmitter output must be maintained at a fixed value, what In all cases other than those in which the transmitter output must be maintained at a fixed value, what amount of power should be employed for routine communications?amount of power should be employed for routine communications? A.The maximum amount of power to maintain communications A.The maximum amount of power to maintain communications B.The transmitter must be maintained at a fixed value B.The transmitter must be maintained at a fixed value C.The minimum amount of power necessary to ensure reliable communications C.The minimum amount of power necessary to ensure reliable communications D.None of the above D.None of the above

6A554 6A554DDWhat is the definition of a "station open to public service"?What is the definition of a "station open to public service"? A.A station which handles public correspondence A.A station which handles public correspondence B.Paid or toll messages B.Paid or toll messages C.Radiotelephone facilities for the general public at prescribed rates C.Radiotelephone facilities for the general public at prescribed rates D.All of the above D.All of the above

6A555 6A555CCIn the transmission of the international Morse code, what are the relative time lengths of dashes, dots?In the transmission of the international Morse code, what are the relative time lengths of dashes, dots? A.Dashes are about four times as long as dots A.Dashes are about four times as long as dots B.Dots are about half the length of dashes B.Dots are about half the length of dashes C.Dashes are about three times as long as dots C.Dashes are about three times as long as dots D.None of the above D.None of the above

6A556 6A556CCWhy is the clock on a compulsorily equipped ship radiotelegraph station required to have a sweep secondWhy is the clock on a compulsorily equipped ship radiotelegraph station required to have a sweep second hand?hand? A.To be able to accurately time the spaces and dashes of the auto-alarm system A.To be able to accurately time the spaces and dashes of the auto-alarm system B.To accurately time the silent periods B.To accurately time the silent periods C.Both A & B C.Both A & B D.None of the above D.None of the above

6A557 6A557CCBetween what points on a ship, compulsorily equipped with a radiotelegraph installation, is a reliable Between what points on a ship, compulsorily equipped with a radiotelegraph installation, is a reliable intercommunication system required?intercommunication system required? A.Between the forward bridge and the radio room A.Between the forward bridge and the radio room B.Between the radio room and engineering B.Between the radio room and engineering C.Between the radio room and the navigation bridge C.Between the radio room and the navigation bridge D.None of the above D.None of the above

6A558 6A558BBAre there any age requirements that a person must meet before he can be issued a radiotelegraph operator Are there any age requirements that a person must meet before he can be issued a radiotelegraph operator license?license? A.At least 18 years of age for a second class license A.At least 18 years of age for a second class license B.At least 21 years of age for a first class license B.At least 21 years of age for a first class license C.Persons under 21 now holding a radiotelegraph first class license may renew same without regard to C.Persons under 21 now holding a radiotelegraph first class license may renew same without regard to age requirementage requirement D.All of the above D.All of the above

6A559 6A559DDUpon compulsorily equipped vessels which are required to have an accurate clock in the radio room, howUpon compulsorily equipped vessels which are required to have an accurate clock in the radio room, how frequently must this clock be adjusted and be compared with standard time?frequently must this clock be adjusted and be compared with standard time? A.Every three hours A.Every three hours B.Ever four hours B.Ever four hours C.Every six hours C.Every six hours D.At least once every 24 hours D.At least once every 24 hours

6A560 6A560DDHow frequently must an entry be made in a ship radiotelegraph log while a radio watch is being How frequently must an entry be made in a ship radiotelegraph log while a radio watch is being maintained?maintained? A.At least every 15 minutes A.At least every 15 minutes B.This is in addition to the entries referring to silent periods B.This is in addition to the entries referring to silent periods C.At least every 30 minutes C.At least every 30 minutes D.Both A & B D.Both A & B

6A561 6A561CCAt what time(s) are routine transmissions forbidden in the bands of 480 to 515 kHz?At what time(s) are routine transmissions forbidden in the bands of 480 to 515 kHz? A.Routine transmissions are forbidden in 480 to 515 kHz A.Routine transmissions are forbidden in 480 to 515 kHz B.480 to 515 kHz are out of the marine radio band B.480 to 515 kHz are out of the marine radio band C.Routine transmissions are forbidden during the international silent period C.Routine transmissions are forbidden during the international silent period D.None of the above D.None of the above

6A562 6A562BBWhat time system shell be used in making log entries with respect to the observance of the international What time system shell be used in making log entries with respect to the observance of the international silent period?silent period? A.Zulu time according to the twelve hour system A.Zulu time according to the twelve hour system B.Greenwich Mean Time according to the 24 hour system B.Greenwich Mean Time according to the 24 hour system C.Zulu time according to the 12 hour time C.Zulu time according to the 12 hour time D.None of the above D.None of the above

6A563 6A563CCWhat is the international radiotelegraph distress frequency for stations in the mobile service?What is the international radiotelegraph distress frequency for stations in the mobile service? A.300 kHz A.300 kHz B.400 kHz B.400 kHz C.500 kHz C.500 kHz D.600 kHz D.600 kHz

6A564 6A564CCDescribe how a distress call should be made:Describe how a distress call should be made: A.The distress call should be made three times A.The distress call should be made three times B.SOS should be called twice B.SOS should be called twice C.The distress call shall include the distress signal transmitted three times, the word DE, and the call C.The distress call shall include the distress signal transmitted three times, the word DE, and the call signal of the mobile station in distress transmitted three timessignal of the mobile station in distress transmitted three times D.None of the above D.None of the above

6A565 6A565AA

What transmission should precede the transmission of the distress call?What transmission should precede the transmission of the distress call? A.The distress call, when sent in radiotelegraph on 500 kHz shall as a general rule, be immediately A.The distress call, when sent in radiotelegraph on 500 kHz shall as a general rule, be immediately preceded by the auto-alarm signalpreceded by the auto-alarm signal B.SOS should be sent three times B.SOS should be sent three times C.The words "MAY DAY" should be sent three times C.The words "MAY DAY" should be sent three times D.None of the above D.None of the above

6A566 6A566DDWhat stations shall be in control of distress traffic?What stations shall be in control of distress traffic? A.Control of the distress traffic shall be with the station first hearing the call A.Control of the distress traffic shall be with the station first hearing the call B.The control of the distress traffic rests with the mobile station in distress B.The control of the distress traffic rests with the mobile station in distress C.With the mobile station which sends the distress call in the event that the station in distress is not able C.With the mobile station which sends the distress call in the event that the station in distress is not able to transmit itto transmit it D.Both B & C D.Both B & C

6A567 6A567AADuring what periods must a distress message be repeated following the initial transmission?During what periods must a distress message be repeated following the initial transmission? A.Until an answer is received, especially during the silent periods A.Until an answer is received, especially during the silent periods B.Must repeated every 15 minutes B.Must repeated every 15 minutes C.Must be repeated every 5 minutes C.Must be repeated every 5 minutes D.Must be repeated every 3 minutes D.Must be repeated every 3 minutes

6A568 6A568AAFor how long must mobile stations listen after hearing an urgency signal?For how long must mobile stations listen after hearing an urgency signal? A.For at least 5 minutes A.For at least 5 minutes B.For at least 30 minutes B.For at least 30 minutes C.For at least 3 minutes C.For at least 3 minutes D.None of the above D.None of the above

6A569 6A569CCWhen the auto-alarm bell rings, what should the operator do?When the auto-alarm bell rings, what should the operator do? A.Proceed immediately to the radio room and press the reset button A.Proceed immediately to the radio room and press the reset button B.If the bell stops, the operator should listen for further signals B.If the bell stops, the operator should listen for further signals C.Both A & B C.Both A & B D.None of the above D.None of the above

6A570 6A570AAWhat space of time should elapse between the transmission of the international auto-alarm signal and the What space of time should elapse between the transmission of the international auto-alarm signal and the distress call?distress call? A.2 minutes A.2 minutes

B.4 minutes B.4 minutes C.5 minutes C.5 minutes D.10 minutes D.10 minutes

6A571 6A571CCWhile a vessel is at sea, how frequently must the auto-alarm be tested?While a vessel is at sea, how frequently must the auto-alarm be tested? A.At least once ever 6 hours A.At least once ever 6 hours B.At least once ever 12 hours B.At least once ever 12 hours C.At least once ever 24 hours C.At least once ever 24 hours D.None of the above D.None of the above

6A5726A572BBUpon hearing an SOS, what should an operator do?Upon hearing an SOS, what should an operator do? A.Should repeat the SOS to all traffic A.Should repeat the SOS to all traffic B.Immediately cease all transmissions capable of interfering with the distress traffic B.Immediately cease all transmissions capable of interfering with the distress traffic C.Contact the vessel in distress C.Contact the vessel in distress D.None of the above D.None of the above

6A573 6A573CCWhat is the purpose of an auto-alarm signal keying device on a compulsorily equipped ship?What is the purpose of an auto-alarm signal keying device on a compulsorily equipped ship? A.To automatically produce Morse code A.To automatically produce Morse code B.To automatically send an SOS signal B.To automatically send an SOS signal C.To automatically produce the correct auto-alarm signal C.To automatically produce the correct auto-alarm signal D.None of the above D.None of the above

6A574 6A574CCOn a United States vessel equipped with an approved auto-alarm, where is the control button which On a United States vessel equipped with an approved auto-alarm, where is the control button which silences the warning bells located?silences the warning bells located? A.On the navigation bridge A.On the navigation bridge B.In main engineering control B.In main engineering control C.In the main radiotelegraph operating room C.In the main radiotelegraph operating room D.None of the above D.None of the above

6A575 6A575CCWith what type(s) of emission and upon what frequency should a transmitter be adjusted to transmit a With what type(s) of emission and upon what frequency should a transmitter be adjusted to transmit a distress call?distress call? A.The distress wave of 600 kHz and type C emission A.The distress wave of 600 kHz and type C emission B.The distress wave of 400 kHz and type C emission B.The distress wave of 400 kHz and type C emission C.The international distress wave of 500 kHz / type A-2 OR B emission C.The international distress wave of 500 kHz / type A-2 OR B emission

D.None of the above D.None of the above

6A576 6A576DDIf you receive a distress call signed by a call signal composed of five letters, could you determine the If you receive a distress call signed by a call signal composed of five letters, could you determine the type of craft which transmitted the signal?type of craft which transmitted the signal? A.Five letter call signals are assigned to aircraft stations A.Five letter call signals are assigned to aircraft stations B.Three letter call signals are assigned to land stations B.Three letter call signals are assigned to land stations C.Four letter call signals are assigned to ship stations C.Four letter call signals are assigned to ship stations D.All of the above D.All of the above

6A5776A577BBWhile the vessel is in the open sea, how frequently must the specific gravity of the emergency battery be While the vessel is in the open sea, how frequently must the specific gravity of the emergency battery be taken?taken? A.Every 12 hours A.Every 12 hours B.Once daily B.Once daily C.Every 48 hours C.Every 48 hours D.Once every week D.Once every week

6A578 6A578DDHow frequently must the quantity of fuel in the supply tank for use with an oil or gas driven emergency How frequently must the quantity of fuel in the supply tank for use with an oil or gas driven emergency generator be checked while the vessel is in the open sea?generator be checked while the vessel is in the open sea? A.Once a week A.Once a week B.Every 12 hours B.Every 12 hours C.Every 48 hours C.Every 48 hours D.Once daily D.Once daily

6A579 6A579DDWhile a vessel is in port, how frequently should the emergency equipment be tested?While a vessel is in port, how frequently should the emergency equipment be tested? A.Once a day A.Once a day B.Once a week B.Once a week C.Once a month C.Once a month D.Only when the vessel is ready to leave port D.Only when the vessel is ready to leave port

6A580 6A580DDYou intercept "CQ CQ WSV TFC"; what does this mean?You intercept "CQ CQ WSV TFC"; what does this mean? A.General call to all stations A.General call to all stations B.Call letter of a coastal station B.Call letter of a coastal station C.Traffic C.Traffic D.All of the above D.All of the above

6A581 6A581CCExplain the use and meaning of the following indicator or prefix "RP" on radiotelegrams:Explain the use and meaning of the following indicator or prefix "RP" on radiotelegrams: A.Please reply A.Please reply B.Repeat following parts of message B.Repeat following parts of message C."Reply paid" C."Reply paid" D.None of the above D.None of the above

6A5826A582CCUpon what band, in addition to the 350 to 515 kHz band must a main receiver on a United States ship be Upon what band, in addition to the 350 to 515 kHz band must a main receiver on a United States ship be capable of operation?capable of operation? A.600 TO 700 kHz A.600 TO 700 kHz B.1000 TO 1200 kHz B.1000 TO 1200 kHz C.100 TO 200 kHz C.100 TO 200 kHz D.516 TO 615 kHz D.516 TO 615 kHz

6A583 6A583BBAfter a distress call has been transmitted, every distress-traffic radiotelegram shall contain what symbol After a distress call has been transmitted, every distress-traffic radiotelegram shall contain what symbol in the preamble?in the preamble? A.SOS followed by the call signal A.SOS followed by the call signal B.The distress signal preceding the call and repeated at the beginning of the preamble B.The distress signal preceding the call and repeated at the beginning of the preamble C.All of the above C.All of the above D.None of the above D.None of the above

6A584 6A584AAFor how long a period of continuous operation should the emergency power supply of a compulsorily For how long a period of continuous operation should the emergency power supply of a compulsorily equipped ship station be capable of energizing the emergency radiotelegraph installation?equipped ship station be capable of energizing the emergency radiotelegraph installation? A.At least 6 consecutive hours A.At least 6 consecutive hours B.At least 12 hours B.At least 12 hours C.At least 24 consecutive hours C.At least 24 consecutive hours D.At least 48 consecutive hours D.At least 48 consecutive hours

6A585 6A585BBWhat is the principal port of the United States, on the Pacific coast, at which navigation lines terminate?What is the principal port of the United States, on the Pacific coast, at which navigation lines terminate? A.Los Angeles A.Los Angeles B.San Francisco B.San Francisco C.San Diego C.San Diego D.None of the above D.None of the above

6A586 6A586BBIn what city is the major telecommunication center of the United States located?In what city is the major telecommunication center of the United States located? A.Houston A.Houston B.New York City B.New York City C.Washington C.Washington D.Chicago D.Chicago

6A5876A587CCUnder what condition may an eligible person hold a radiotelegraph operator's license and a Marine Radio Under what condition may an eligible person hold a radiotelegraph operator's license and a Marine Radio Operator permit?Operator permit? A.When the planned telegraphy operation will occur aboard ship in international waters and another A.When the planned telegraphy operation will occur aboard ship in international waters and another vessel is licensed for operation on the inland waterwaysvessel is licensed for operation on the inland waterways B.When the commercial radio operator is legally eligible for both foreign and domestic employment B.When the commercial radio operator is legally eligible for both foreign and domestic employment C.No person may hold any class of radiotelegraph operator's certificate and a Marine Radio Operator C.No person may hold any class of radiotelegraph operator's certificate and a Marine Radio Operator PermitPermit D.Commercial radiotelegraphers are required to also hold a Marine Radio Operator Permit when the D.Commercial radiotelegraphers are required to also hold a Marine Radio Operator Permit when the operation occurs on vessels of less than 1600 gross tonsoperation occurs on vessels of less than 1600 gross tons

6A588 6A588CCHow does a First Class Radiotelegraph Operator renew an unexpired license?How does a First Class Radiotelegraph Operator renew an unexpired license? A.Renewal document indicating license serial number must be forwarded to the FCC during the last 90 A.Renewal document indicating license serial number must be forwarded to the FCC during the last 90 days of the license termdays of the license term B.Application is made to the nearest Commercial Operator Licensing Examination Manager (COLEM) B.Application is made to the nearest Commercial Operator Licensing Examination Manager (COLEM) during the final six months of the license termduring the final six months of the license term C.By submitting Form 756, current license copy, and appropriate fee to the FCC during the last year of C.By submitting Form 756, current license copy, and appropriate fee to the FCC during the last year of the five year license termthe five year license term D.A current Radio telegraphy Proficiency Testimonial (RPT) obtained from the ship's master must be D.A current Radio telegraphy Proficiency Testimonial (RPT) obtained from the ship's master must be attached to the renewal application Form 739attached to the renewal application Form 739

6A589 6A589AAHow does an eligible Second Class Radiotelegraph Operator upgrade his license to First Class?How does an eligible Second Class Radiotelegraph Operator upgrade his license to First Class? A.By submitting the necessary Proof-of-Passing Certificates (PPC) from a COLEM along with the A.By submitting the necessary Proof-of-Passing Certificates (PPC) from a COLEM along with the required fee and Form 756 to the FCCrequired fee and Form 756 to the FCC B.By fulfilling the Six Months Service Endorsement requirement B.By fulfilling the Six Months Service Endorsement requirement C.By presenting a one year radiotelegraph experience certification to a commercial radio operator C.By presenting a one year radiotelegraph experience certification to a commercial radio operator examination managerexamination manager D.By complying with the ITU Provision "D" concerning telegraphy operation in the Maritime Service D.By complying with the ITU Provision "D" concerning telegraphy operation in the Maritime Service

6A590 6A590

DDWhat is the license term of the First Class Radiotelegraph Operator License?What is the license term of the First Class Radiotelegraph Operator License? A.The license is valid for the lifetime of the holder A.The license is valid for the lifetime of the holder B.A license is valid for a period of ten years form the DOI (date of issuance) B.A license is valid for a period of ten years form the DOI (date of issuance) C.The five year term license is renewable by retaking updated exam Elements 1 and 3 during the last 90 C.The five year term license is renewable by retaking updated exam Elements 1 and 3 during the last 90 days before expirationdays before expiration D.The license term is five years and may be renewed indefinitely without retesting D.The license term is five years and may be renewed indefinitely without retesting

6A5916A591BBWhat is a requirement of every commercial operator on duty and in charge of a transmitting system?What is a requirement of every commercial operator on duty and in charge of a transmitting system? A.A copy of the Proof-of-Passing Certificate (PPC) must be on display at the transmitter location A.A copy of the Proof-of-Passing Certificate (PPC) must be on display at the transmitter location B.The original license or a photocopy must be posted or in the operator's personal possession and B.The original license or a photocopy must be posted or in the operator's personal possession and available for inspectionavailable for inspection C.The FCC Form 756 certifying the operator's qualifications must be readily available at the transmitting C.The FCC Form 756 certifying the operator's qualifications must be readily available at the transmitting system sitesystem site D.A copy of the operator's license must be supplied to the radio station's supervisor as evidence of D.A copy of the operator's license must be supplied to the radio station's supervisor as evidence of technical qualificationtechnical qualification

6A592 6A592CCWhat is the experience requirement of a First Class Radiotelegrapher?What is the experience requirement of a First Class Radiotelegrapher? A.The applicant must have been employed as a radio operator on board a United States ship for at least A.The applicant must have been employed as a radio operator on board a United States ship for at least six monthssix months B.The operator must have held a Second Class Radiotelegraph Operator's Certificate for at least six B.The operator must have held a Second Class Radiotelegraph Operator's Certificate for at least six monthsmonths C.The applicant must have a background of sending or receiving radiotelegraph messages for one year C.The applicant must have a background of sending or receiving radiotelegraph messages for one year D.Both A & B D.Both A & B

6A593 6A593CCWhat examination requirements are necessary to obtain a Second Class Radiotelegraph Operator's What examination requirements are necessary to obtain a Second Class Radiotelegraph Operator's Certificate?Certificate? A.Written Element 1 (radio law), Element 3 (electronic fundamentals), Element 5 (radiotelegraph A.Written Element 1 (radio law), Element 3 (electronic fundamentals), Element 5 (radiotelegraph operations) and sending/receiving 16/20 words per minuteoperations) and sending/receiving 16/20 words per minute B.Telegraphy Element 1 (sending/receiving 16 code groups per minute) and Telegraphy Element 2 (16 B.Telegraphy Element 1 (sending/receiving 16 code groups per minute) and Telegraphy Element 2 (16 code groups and 20 words per minute text.)code groups and 20 words per minute text.) C.Successful completion of written test Elements 1, 5 and 6 on basic radio law and operating practices C.Successful completion of written test Elements 1, 5 and 6 on basic radio law and operating practices plus telegraphy Elements 1 and 2plus telegraphy Elements 1 and 2 D.Successful completion of written test Elements 1, 3, 5 and 6 on basic radio law and operating practices D.Successful completion of written test Elements 1, 3, 5 and 6 on basic radio law and operating practices plus telegraphy Elements 1 and Bplus telegraphy Elements 1 and B

6A594 6A594AA

How does an applicant qualify for a Third Class Radiotelegraph Operator's Certificate?How does an applicant qualify for a Third Class Radiotelegraph Operator's Certificate? A.By passing the appropriate written examinations and receiving by ear code groups and plain text for a A.By passing the appropriate written examinations and receiving by ear code groups and plain text for a period of one minute without error at the appropriate speedperiod of one minute without error at the appropriate speed B.Applicant must send and receive radiotelegraphy at the prescribed speed and be at least 21 years old B.Applicant must send and receive radiotelegraphy at the prescribed speed and be at least 21 years old C.By the successful completion of radiotelegraphy Elements 1 and 2 plus written examinations on radio C.By the successful completion of radiotelegraphy Elements 1 and 2 plus written examinations on radio law, telegraphy practices and transmitter maintenancelaw, telegraphy practices and transmitter maintenance D.By passing a written examination on radio law, electronic fundamentals and radiotelegraph practices D.By passing a written examination on radio law, electronic fundamentals and radiotelegraph practices plus a telegraphy receiving examinationplus a telegraphy receiving examination

6A595 6A595CCWhat examination credit is accorded Amateur Extra Class operators?What examination credit is accorded Amateur Extra Class operators? A.20 code groups and 25 text words per minute A.20 code groups and 25 text words per minute B.Amateur radio operators are not eligible for commercial radio operator examination credit B.Amateur radio operators are not eligible for commercial radio operator examination credit C.Commercial radio operator telegraphy Elements 1 and 2 C.Commercial radio operator telegraphy Elements 1 and 2 D.Written Element 1, basic radio law and operating practices D.Written Element 1, basic radio law and operating practices

6A596 6A596DDWhat must every examination for the code portion of a radiotelegraph license contain?What must every examination for the code portion of a radiotelegraph license contain? A.Applicants for Commercial Radiotelegraph licenses must be examined using a message format that A.Applicants for Commercial Radiotelegraph licenses must be examined using a message format that they are likely to receive aboard shipthey are likely to receive aboard ship B.Both a telegraphy sending and a receiving distress signals B.Both a telegraphy sending and a receiving distress signals C.The proper transmission of radiotelegraph distress signals C.The proper transmission of radiotelegraph distress signals D.All alphabet letters, all numerals, period, comma, question mark, slant mark and prosigns AR, BT, D.All alphabet letters, all numerals, period, comma, question mark, slant mark and prosigns AR, BT, and SKand SK

6A597 6A597CCWhat answer format is accepted on commercial radiotelegraph license contain?What answer format is accepted on commercial radiotelegraph license contain? A.The examiner may use any answer format which ascertains that the examinee can comprehend the A.The examiner may use any answer format which ascertains that the examinee can comprehend the message transmittedmessage transmitted B.Any of the following: one minute solid copy, answering seven out of ten question, fill-in-the-blank, or B.Any of the following: one minute solid copy, answering seven out of ten question, fill-in-the-blank, or multiple choice questionsmultiple choice questions C.Examinees are required to receive international Morse code messages by ear for a period of one C.Examinees are required to receive international Morse code messages by ear for a period of one minute without errorminute without error D.Examinees must obtain a passing mark of 75% or higher on questions concerning the transmitted D.Examinees must obtain a passing mark of 75% or higher on questions concerning the transmitted telegraphy messagetelegraphy message

6A598 6A598CCWhat is a requirement of all transmitting apparatus used aboard United States vessels?What is a requirement of all transmitting apparatus used aboard United States vessels? A.Equipment must be approved by the U.S. Coast Guard for maritime mobile use A.Equipment must be approved by the U.S. Coast Guard for maritime mobile use B.Certification is required by the International Maritime Organization (IMO) B.Certification is required by the International Maritime Organization (IMO) C.Only equipment that has been type accepted by the FCC for Part 80 operations is authorized C.Only equipment that has been type accepted by the FCC for Part 80 operations is authorized D.Programming of all maritime channels must be performed by a licensed Marine Radio Operator D.Programming of all maritime channels must be performed by a licensed Marine Radio Operator

6A5996A599CCWhat happens to a lower grade of Commercial Radiotelegraph License when a licensee qualifies for a What happens to a lower grade of Commercial Radiotelegraph License when a licensee qualifies for a higher grade?higher grade? A.The lower grade is allowed to expire and may not be renewed A.The lower grade is allowed to expire and may not be renewed B.The Second or Third Class Radiotelegraph license is modified to a higher class B.The Second or Third Class Radiotelegraph license is modified to a higher class C.The lower grade is canceled. Only one unexpired radiotelegraph operator's certificate may be held at C.The lower grade is canceled. Only one unexpired radiotelegraph operator's certificate may be held at the same timethe same time D.Licensees are permitted to hold any number of radiotelegraph operator certificates at the same time D.Licensees are permitted to hold any number of radiotelegraph operator certificates at the same time

6A600 6A600AAWhat is an operating control requirement of a ship station using telegraphy?What is an operating control requirement of a ship station using telegraphy? A.The ship station must be capable of automatically changing from telegraphy transmission to telegraph A.The ship station must be capable of automatically changing from telegraphy transmission to telegraph receptionreception B.A ship station control operator must stand watch on emergency channels at all times B.A ship station control operator must stand watch on emergency channels at all times C.Only a licensed First Class Radiotelegraph Operator may operate a ship station C.Only a licensed First Class Radiotelegraph Operator may operate a ship station D.The ship station must be capable of changing from one radio channel to another within five seconds D.The ship station must be capable of changing from one radio channel to another within five seconds

6A601 6A601BBHow does a radiotelegraph operator transmit a routine call to another station?How does a radiotelegraph operator transmit a routine call to another station? A.The letters "CQ" are followed by the call sign of the station called and the call sign of the originating A.The letters "CQ" are followed by the call sign of the station called and the call sign of the originating stationstation B.The station is called not more than twice, followed by the word "DE" and the call sign of the calling B.The station is called not more than twice, followed by the word "DE" and the call sign of the calling station not more than twicestation not more than twice C.The originating station must obtain permission from the nearest public coast station C.The originating station must obtain permission from the nearest public coast station D.Routine calls are initiated by using the appropriate service abbreviation D.Routine calls are initiated by using the appropriate service abbreviation

6A602 6A602BBWhat is the proper procedure to conduct a radiotelegraph equipment test?What is the proper procedure to conduct a radiotelegraph equipment test? A.By transmitting "EI" on the test frequency as a warning that a test transmission is about to be made A.By transmitting "EI" on the test frequency as a warning that a test transmission is about to be made B.Sending a series of "VVV" followed by the call sign of the testing station at about 10 words-per- B.Sending a series of "VVV" followed by the call sign of the testing station at about 10 words-per-minuteminute C.The test transmission may not proceed until all stations on frequency have signalled their consent C.The test transmission may not proceed until all stations on frequency have signalled their consent D.The nearest public or private coast station must be notified of an impending test D.The nearest public or private coast station must be notified of an impending test

6A603 6A603

AAHow often must a radiotelegraph station transmit its call sign when a transmission is maintained for moreHow often must a radiotelegraph station transmit its call sign when a transmission is maintained for more than 20 minutes in the band 405-525 kHz?than 20 minutes in the band 405-525 kHz? A.At 20 minute intervals A.At 20 minute intervals B.At least every 10 minutes B.At least every 10 minutes C.At 15 minute intervals unless public correspondence is in progress C.At 15 minute intervals unless public correspondence is in progress D.At the beginning and end of each communication with any other station D.At the beginning and end of each communication with any other station

6A604 6A604CCWhen may a public coast station authorized to use high frequency narrow-band direct-printing (NB-DP) When may a public coast station authorized to use high frequency narrow-band direct-printing (NB-DP) establish contact with a ship station using telegraphy?establish contact with a ship station using telegraphy? A.Never. Contact may only be established using NB-DP circuits A.Never. Contact may only be established using NB-DP circuits B.When the ship is in excess of 300 gross tons B.When the ship is in excess of 300 gross tons C.When the radio station license reflects authority for this type of operation and harmful interference is C.When the radio station license reflects authority for this type of operation and harmful interference is avoidedavoided D.When it is known that the vessel does not have a selective ringing or calling device D.When it is known that the vessel does not have a selective ringing or calling device

6A605 6A605CCWhich operator is authorized to make equipment adjustments at maritime radio stations which may affectWhich operator is authorized to make equipment adjustments at maritime radio stations which may affect transmitter operation?transmitter operation? A.The holder of a marine radio operator permit or higher class license A.The holder of a marine radio operator permit or higher class license B.The holder of a restricted radiotelephone operator permit when the radiated power is less than 100 B.The holder of a restricted radiotelephone operator permit when the radiated power is less than 100 wattswatts C.Only the holders of a first or second class radiotelegraph of the general radiotelephone operator's C.Only the holders of a first or second class radiotelegraph of the general radiotelephone operator's licenselicense D.The holder of a GMDSS radio operator or higher class radiotelephone license D.The holder of a GMDSS radio operator or higher class radiotelephone license

6A606 6A606AAWho may install, maintain or adjust radiotelephone transmitters which radiate less than 50 watts carrier Who may install, maintain or adjust radiotelephone transmitters which radiate less than 50 watts carrier power?power? A.Anyone under the immediate supervision and responsibility of a person holding a first of second class A.Anyone under the immediate supervision and responsibility of a person holding a first of second class radiotelegraph or general radiotelephone operator licenseradiotelegraph or general radiotelephone operator license B.Only a properly licensed radiotelephone operator B.Only a properly licensed radiotelephone operator C.Any holder of a marine radio operator permit or higher C.Any holder of a marine radio operator permit or higher D.Only persons holding an operator certificate containing a ship radar endorsement D.Only persons holding an operator certificate containing a ship radar endorsement

6A607 6A607DDWho may program authorized frequency channels into a transmitter or transceiver used in the maritime Who may program authorized frequency channels into a transmitter or transceiver used in the maritime service?service? A.Any person who has the authorization of the station licensee or ship's master A.Any person who has the authorization of the station licensee or ship's master B.A licensed marine radio operator or higher B.A licensed marine radio operator or higher C.A person holding a restricted radiotelephone operator permit or higher C.A person holding a restricted radiotelephone operator permit or higher

D.Only persons holding a first or second class radiotelegraph operator's certificate or a general D.Only persons holding a first or second class radiotelegraph operator's certificate or a general radiotelephone operator's licenseradiotelephone operator's license

6A608 6A608AAWhat is the maximum authorized bandwidth of a high frequency radiotelegraphy signal, emission A1A, What is the maximum authorized bandwidth of a high frequency radiotelegraphy signal, emission A1A, in the maritime service?in the maritime service? A.0.4 kHz A.0.4 kHz B.0.2 kHz B.0.2 kHz C.Minimum necessary to complete necessary communications C.Minimum necessary to complete necessary communications D.1 kHz D.1 kHz

6A609 6A609CCWhat is the maximum transmitter power that a ship station may radiate using radiotelegraphy emissions What is the maximum transmitter power that a ship station may radiate using radiotelegraphy emissions on frequencies below 27500 kHz?on frequencies below 27500 kHz? A.400 W A.400 W B.2 kW, unless a passenger ship 5000 gross tons and over B.2 kW, unless a passenger ship 5000 gross tons and over C.3 kW C.3 kW D.1 kW D.1 kW

6A610 6A610CCWhere must ship station logs be kept during a voyage?Where must ship station logs be kept during a voyage? A.They must be secured in the vessel's strongbox for safekeeping A.They must be secured in the vessel's strongbox for safekeeping B.In the personal custody of the licensed commercial radio operator B.In the personal custody of the licensed commercial radio operator C.At the principal radiotelephone operating position or radiotelegraph operating room C.At the principal radiotelephone operating position or radiotelegraph operating room D.All logs are turned over to the ship's master when the radio operator goes off duty D.All logs are turned over to the ship's master when the radio operator goes off duty

6A611 6A611DDHow often must compulsory radiotelegraph installations on passenger vessels be inspected?How often must compulsory radiotelegraph installations on passenger vessels be inspected? A.When the vessel is placed in service and every 2 years thereafter A.When the vessel is placed in service and every 2 years thereafter B.At least every 3 years when the ship is within 75 miles of an FCC field office B.At least every 3 years when the ship is within 75 miles of an FCC field office C.The ship's master is responsible for completion of the Annual Equipment Verification Report C.The ship's master is responsible for completion of the Annual Equipment Verification Report D.Equipment inspections are required at least once every 12 months D.Equipment inspections are required at least once every 12 months

6A612 6A612BBWhat is the antenna requirement aboard a survival craft equipped with a non-portable radiotelegraph What is the antenna requirement aboard a survival craft equipped with a non-portable radiotelegraph installation?installation?

A.The minimum lifeboat antenna requirement is an HF half-wave dipole capable of efficiently tuning A.The minimum lifeboat antenna requirement is an HF half-wave dipole capable of efficiently tuning distress frequenciesdistress frequencies B.The antenna must be single wire inverted L type of maximum practicable length and height above the B.The antenna must be single wire inverted L type of maximum practicable length and height above the waterlinewaterline C.The antenna must be tested at least once during each voyage and a minimum of once a week on longer C.The antenna must be tested at least once during each voyage and a minimum of once a week on longer voyagesvoyages D.The antenna must be located a minimum of 8 meters above the waterline to insure the safety of D.The antenna must be located a minimum of 8 meters above the waterline to insure the safety of passengerspassengers

6A613 6A613CCWhat document is issued after a radio station inspection aboard a large ship that is not a passenger What document is issued after a radio station inspection aboard a large ship that is not a passenger vessel?vessel? A.Great Lakes Radio Agreement surety authorization A.Great Lakes Radio Agreement surety authorization B.International Maritime Organization safety permit B.International Maritime Organization safety permit C.Cargo ship safety radiotelegraphy or radiotelephony certificate C.Cargo ship safety radiotelegraphy or radiotelephony certificate D.Safety Convention radio certification D.Safety Convention radio certification

6A614 6A614BBWhat is the minimum radio operator license requirement of a chief radio officer on U.S. passenger ships?What is the minimum radio operator license requirement of a chief radio officer on U.S. passenger ships? A.First or Second Class Radiotelegraph Operator Certificate with six month endorsement A.First or Second Class Radiotelegraph Operator Certificate with six month endorsement B.First Class Radiotelegraph Operator Certificate B.First Class Radiotelegraph Operator Certificate C.General Radiotelephone Operator License C.General Radiotelephone Operator License D.Marine Radio Operator Permit D.Marine Radio Operator Permit

6A615 6A615CCWhat is the order of priority of radiotelegraph communications in the maritime services?What is the order of priority of radiotelegraph communications in the maritime services? A.Alarm, radio-direction finding, and health and welfare communications A.Alarm, radio-direction finding, and health and welfare communications B.Navigation hazards, meteorological warnings, priority traffic B.Navigation hazards, meteorological warnings, priority traffic C.Distress calls, and signals, followed by communications preceded by urgency and safety signals C.Distress calls, and signals, followed by communications preceded by urgency and safety signals D.Government precedence, messages concerning safety of life and protection of property and traffic D.Government precedence, messages concerning safety of life and protection of property and traffic concerning grave imminent dangerconcerning grave imminent danger

6A616 6A616BBWhat should a station operator do before making a transmission?What should a station operator do before making a transmission? A.Check transmitting equipment to be certain it is properly calibrated A.Check transmitting equipment to be certain it is properly calibrated B.Except for the transmission of distress calls, determine that the frequency is not in use by monitoring B.Except for the transmission of distress calls, determine that the frequency is not in use by monitoring the frequency before transmittingthe frequency before transmitting C.Ask if the frequency is in use C.Ask if the frequency is in use D.Transmit a general notification that the operator wishes to utilize the channel D.Transmit a general notification that the operator wishes to utilize the channel