Electrical and RF Safety 1 G0 - ELECTRICAL AND RF SAFETY [2 Exam Questions - 2 groups] G0ARF safety principles, rules and guidelines; routine station evaluation

Electrical and RF Safety1

G0 - ELECTRICAL AND RF SAFETY G0 - ELECTRICAL AND RF SAFETY [2 Exam Questions - 2 groups][2 Exam Questions - 2 groups]

G0AG0A RF safety principles, rules and guidelines; routine RF safety principles, rules and guidelines; routine station evaluationstation evaluation

G0BG0B Safety in the ham shack: electrical shock and Safety in the ham shack: electrical shock and treatment, grounding, fusing, interlocks, wiring, treatment, grounding, fusing, interlocks, wiring, antenna and tower safetyantenna and tower safety

G0A Electrical and RF SafetyG0A Electrical and RF Safety

• RF safety principles, rules & guidelinesRF safety principles, rules & guidelines

• RF energy can heat human body tissueRF energy can heat human body tissue• RF safety rules require no further action when the RF safety rules require no further action when the

maximum power output capability of an otherwise maximum power output capability of an otherwise compliant station is reducedcompliant station is reduced

• TURN OFF THE TRANSMITTER AND TURN OFF THE TRANSMITTER AND DISCONNECT THE FEEDLINE DISCONNECT THE FEEDLINE whenever you make whenever you make adjustments or repairs to an antennaadjustments or repairs to an antenna

• If an evaluation of your stations shows RF energy If an evaluation of your stations shows RF energy radiated exceeds permissible limitsradiated exceeds permissible limits you must you must take take action to prevent human exposure to the excessive action to prevent human exposure to the excessive RF fieldsRF fields


G0A Safety principles, rules & G0A Safety principles, rules & guidelines cont’dguidelines cont’d

• You should make sure the MPE limits are not You should make sure the MPE limits are not exceeded in occupied areas if you install an indoor exceeded in occupied areas if you install an indoor transmitting antennatransmitting antenna

• When installing a ground-mounted antenna it When installing a ground-mounted antenna it should be installed so no one can be exposed to RF should be installed so no one can be exposed to RF radiation in excess of maximum permissible limitsradiation in excess of maximum permissible limits

• If evaluation shows that a neighbor might receive If evaluation shows that a neighbor might receive more than the allowable limit of RF exposure from more than the allowable limit of RF exposure from the main lobe of a directional antenna take the main lobe of a directional antenna take precaution to ensure that the antenna cannot be precaution to ensure that the antenna cannot be pointed at their housepointed at their house


G0A Routine station evaluationG0A Routine station evaluation• An amateur operator An amateur operator must perform a routine RF must perform a routine RF

exposure evaluation to ensure compliance with RF exposure evaluation to ensure compliance with RF safety regulationssafety regulations

• Any transmitter that contributes 5 per cent Any transmitter that contributes 5 per cent or more of the MPE at a multiple user site or more of the MPE at a multiple user site is/are responsible for RF safety complianceis/are responsible for RF safety compliance

• You can determine that your station complies You can determine that your station complies with FCC RF exposure regulationswith FCC RF exposure regulations• By calculation based on FCC OET Bulletin 65By calculation based on FCC OET Bulletin 65• By calculation based on computer modelingBy calculation based on computer modeling• By measurement of field strength using calibrated By measurement of field strength using calibrated

equipmentequipment


G0A Routine station evaluation cont’dG0A Routine station evaluation cont’d

• A calibrated field-strength meter with a calibrated A calibrated field-strength meter with a calibrated antenna antenna can be used to accurately measure an RF fieldcan be used to accurately measure an RF field

• Critical angle Critical angle is NOT important in estimating if an RF is NOT important in estimating if an RF signal exceeds the maximum permissible exposure signal exceeds the maximum permissible exposure (MPE)(MPE)

• The power level and frequency of the energy The power level and frequency of the energy have have the most direct effect on the permitted exposure level the most direct effect on the permitted exposure level of RF radiationof RF radiation

• ““Time averaging” Time averaging” means the total RF exposure means the total RF exposure average over a certain time in reference to RF radiation average over a certain time in reference to RF radiation exposureexposure

• A lower transmitter duty cycle A lower transmitter duty cycle permits greater permits greater short-term exposure levels when evaluating RF short-term exposure levels when evaluating RF exposureexposure



G0A01 What is one way that RF energy G0A01 What is one way that RF energy can affect human body tissue?can affect human body tissue?

A.A. It heats body tissueIt heats body tissue

B.B. It causes radiation poisoningIt causes radiation poisoning

C.C. It causes the blood count to reach a dangerously It causes the blood count to reach a dangerously low levellow level

D.D. It cools body tissueIt cools body tissue


G0A01 What is one way that RF energy G0A01 What is one way that RF energy can affect human body tissue?can affect human body tissue?

A.A. It heats body tissueIt heats body tissueB.B. It causes radiation poisoningIt causes radiation poisoning

C.C. It causes the blood count to reach a dangerously It causes the blood count to reach a dangerously low levellow level

D.D. It cools body tissueIt cools body tissue


G0A02 Which property is NOT G0A02 Which property is NOT important in estimating if an RF signal important in estimating if an RF signal exceeds the maximum permissible exceeds the maximum permissible exposure (MPE)?exposure (MPE)?

A.A. Its duty cycleIts duty cycle

B.B. Its critical angleIts critical angle

C.C. Its power densityIts power density

D.D. Its frequencyIts frequency


G0A02 Which property is NOT G0A02 Which property is NOT important in estimating if an RF signal important in estimating if an RF signal exceeds the maximum permissible exceeds the maximum permissible exposure (MPE)?exposure (MPE)?

A.A. Its duty cycleIts duty cycle

B.B. Its critical angleIts critical angleC.C. Its power densityIts power density

D.D. Its frequencyIts frequency


G0A03 Which of the following has the G0A03 Which of the following has the most direct effect on the permitted most direct effect on the permitted exposure level of RF radiation?exposure level of RF radiation?

A.A. The age of the person exposedThe age of the person exposed

B.B. The power level and frequency of the energyThe power level and frequency of the energy

C.C. The environment near the transmitterThe environment near the transmitter

D.D. The type of transmission line usedThe type of transmission line used


G0A03 Which of the following has the G0A03 Which of the following has the most direct effect on the permitted most direct effect on the permitted exposure level of RF radiation?exposure level of RF radiation?

A.A. The age of the person exposedThe age of the person exposed

B.B. The power level and frequency of the The power level and frequency of the energyenergy

C.C. The environment near the transmitterThe environment near the transmitter

D.D. The type of transmission line usedThe type of transmission line used


Time Averaged Exposure CalculationsTime Averaged Exposure Calculations


G0A04 What does "time averaging" G0A04 What does "time averaging" mean in reference to RF radiation mean in reference to RF radiation exposure?exposure?

A.A. The average time of day when the exposure occursThe average time of day when the exposure occurs

B.B. The average time it takes RF radiation to have any The average time it takes RF radiation to have any long-term effect on the bodylong-term effect on the body

C.C. The total time of the exposureThe total time of the exposure

D.D. The total RF exposure averaged over a certain timeThe total RF exposure averaged over a certain time


G0A04 What does "time averaging" G0A04 What does "time averaging" mean in reference to RF radiation mean in reference to RF radiation exposure?exposure?

A.A. The average time of day when the exposure occursThe average time of day when the exposure occurs

B.B. The average time it takes RF radiation to have any The average time it takes RF radiation to have any long-term effect on the bodylong-term effect on the body

C.C. The total time of the exposureThe total time of the exposure

D.D. The total RF exposure averaged over a The total RF exposure averaged over a certain timecertain time


G0A05 What must you do if an G0A05 What must you do if an evaluation of your station shows RF evaluation of your station shows RF energy radiated from your station energy radiated from your station exceeds permissible limits?exceeds permissible limits?

A.A. Take action to prevent human exposure to the Take action to prevent human exposure to the excessive RF fieldsexcessive RF fields

B.B. File an Environmental Impact Statement (EIS-97) File an Environmental Impact Statement (EIS-97) with the FCCwith the FCC

C.C. Secure written permission from your neighbors to Secure written permission from your neighbors to operate above the controlled MPE limitsoperate above the controlled MPE limits

D.D. All of these answers are correctAll of these answers are correct


G0A05 What must you do if an G0A05 What must you do if an evaluation of your station shows RF evaluation of your station shows RF energy radiated from your station energy radiated from your station exceeds permissible limits?exceeds permissible limits?

A.A. Take action to prevent human exposure to Take action to prevent human exposure to the excessive RF fieldsthe excessive RF fields

B.B. File an Environmental Impact Statement (EIS-97) File an Environmental Impact Statement (EIS-97) with the FCCwith the FCC

C.C. Secure written permission from your neighbors to Secure written permission from your neighbors to operate above the controlled MPE limitsoperate above the controlled MPE limits



G0A06 Which transmitter(s) at a G0A06 Which transmitter(s) at a multiple user site is/are responsible for multiple user site is/are responsible for RF safety compliance?RF safety compliance?

A.A. Only the most powerful transmitter on siteOnly the most powerful transmitter on site

B.B. All transmitters on site, regardless of their power All transmitters on site, regardless of their power level or duty cyclelevel or duty cycle

C.C. Any transmitter that contributes 5% or more of the Any transmitter that contributes 5% or more of the MPEMPE

D.D. Only those that operate at more than 50% duty Only those that operate at more than 50% duty cyclecycle


G0A06 Which transmitter(s) at a G0A06 Which transmitter(s) at a multiple user site is/are responsible for multiple user site is/are responsible for RF safety compliance?RF safety compliance?

A.A. Only the most powerful transmitter on siteOnly the most powerful transmitter on site

B.B. All transmitters on site, regardless of their power All transmitters on site, regardless of their power level or duty cyclelevel or duty cycle

C.C. Any transmitter that contributes 5% or Any transmitter that contributes 5% or more of the MPEmore of the MPE

D.D. Only those that operate at more than 50% duty Only those that operate at more than 50% duty cyclecycle


G0A07 What effect does transmitter G0A07 What effect does transmitter duty cycle have when evaluating RF duty cycle have when evaluating RF exposure?exposure?

A.A. A lower transmitter duty cycle permits greater A lower transmitter duty cycle permits greater short-term exposure levelsshort-term exposure levels

B.B. A higher transmitter duty cycle permits greater A higher transmitter duty cycle permits greater short-term exposure levelsshort-term exposure levels

C.C. Low duty cycle transmitters are exempt from RF Low duty cycle transmitters are exempt from RF exposure evaluation requirementsexposure evaluation requirements

D.D. Only those transmitters that operate at a 100% Only those transmitters that operate at a 100% duty cycle must be evaluatedduty cycle must be evaluated


G0A07 What effect does transmitter G0A07 What effect does transmitter duty cycle have when evaluating RF duty cycle have when evaluating RF exposure?exposure?

A.A. A lower transmitter duty cycle permits A lower transmitter duty cycle permits greater short-term exposure levelsgreater short-term exposure levels

B.B. A higher transmitter duty cycle permits greater A higher transmitter duty cycle permits greater short-term exposure levelsshort-term exposure levels

C.C. Low duty cycle transmitters are exempt from RF Low duty cycle transmitters are exempt from RF exposure evaluation requirementsexposure evaluation requirements

D.D. Only those transmitters that operate at a 100% Only those transmitters that operate at a 100% duty cycle must be evaluatedduty cycle must be evaluated


G0A08 Which of the following steps G0A08 Which of the following steps must an amateur operator take to must an amateur operator take to ensure compliance with RF safety ensure compliance with RF safety regulations?regulations?

A.A. Post a copy of FCC Part 97 in the stationPost a copy of FCC Part 97 in the station

B.B. Post a copy of OET Bulletin 65 in the stationPost a copy of OET Bulletin 65 in the station

C.C. Perform a routine RF exposure evaluationPerform a routine RF exposure evaluation

D.D. All of these choices are correctAll of these choices are correct


G0A08 Which of the following steps G0A08 Which of the following steps must an amateur operator take to must an amateur operator take to ensure compliance with RF safety ensure compliance with RF safety regulations?regulations?

A.A. Post a copy of FCC Part 97 in the stationPost a copy of FCC Part 97 in the station

B.B. Post a copy of OET Bulletin 65 in the stationPost a copy of OET Bulletin 65 in the station

C.C. Perform a routine RF exposure evaluationPerform a routine RF exposure evaluationD.D. All of these choices are correctAll of these choices are correct


G0A09 What type of instrument can be G0A09 What type of instrument can be used to accurately measure an RF field?used to accurately measure an RF field?

A.A. A receiver with an S meterA receiver with an S meter

B.B. A calibrated field-strength meter with a calibrated A calibrated field-strength meter with a calibrated antennaantenna

C.C. A betascope with a dummy antenna calibrated at A betascope with a dummy antenna calibrated at 50 ohms50 ohms

D.D. An oscilloscope with a high-stability crystal marker An oscilloscope with a high-stability crystal marker generatorgenerator


G0A09 What type of instrument can be G0A09 What type of instrument can be used to accurately measure an RF field?used to accurately measure an RF field?

A.A. A receiver with an S meterA receiver with an S meter

B.B. A calibrated field-strength meter with a A calibrated field-strength meter with a calibrated antennacalibrated antenna

C.C. A betascope with a dummy antenna calibrated at A betascope with a dummy antenna calibrated at 50 ohms50 ohms

D.D. An oscilloscope with a high-stability crystal marker An oscilloscope with a high-stability crystal marker generatorgenerator


G0A10 What do the RF safety rules G0A10 What do the RF safety rules require when the maximum power require when the maximum power output capability of an otherwise output capability of an otherwise compliant station is reduced?compliant station is reduced?

A.A. Filing of the changes with the FCCFiling of the changes with the FCC

B.B. Recording of the power level changes in the log or Recording of the power level changes in the log or station recordsstation records

C.C. Performance of a routine RF exposure evaluationPerformance of a routine RF exposure evaluation

D.D. No further action is requiredNo further action is required


G0A10 What do the RF safety rules G0A10 What do the RF safety rules require when the maximum power require when the maximum power output capability of an otherwise output capability of an otherwise compliant station is reduced?compliant station is reduced?

A.A. Filing of the changes with the FCCFiling of the changes with the FCC

B.B. Recording of the power level changes in the log or Recording of the power level changes in the log or station recordsstation records

C.C. Performance of a routine RF exposure evaluationPerformance of a routine RF exposure evaluation

D.D. No further action is requiredNo further action is required


G0A11 What precaution should you G0A11 What precaution should you take if you install an indoor take if you install an indoor transmitting antenna?transmitting antenna?

A.A. Locate the antenna close to your operating position Locate the antenna close to your operating position to minimize feed line radiationto minimize feed line radiation

B.B. Position the antenna along the edge of a wall to Position the antenna along the edge of a wall to reduce parasitic radiationreduce parasitic radiation

C.C. Make sure that MPE limits are not exceeded in Make sure that MPE limits are not exceeded in occupied areasoccupied areas

D.D. No special precautions are necessary if SSB and CW No special precautions are necessary if SSB and CW are the only modes usedare the only modes used


G0A11 What precaution should you G0A11 What precaution should you take if you install an indoor take if you install an indoor transmitting antenna?transmitting antenna?

A.A. Locate the antenna close to your operating position Locate the antenna close to your operating position to minimize feed line radiationto minimize feed line radiation

B.B. Position the antenna along the edge of a wall to Position the antenna along the edge of a wall to reduce parasitic radiationreduce parasitic radiation

C.C. Make sure that MPE limits are not Make sure that MPE limits are not exceeded in occupied areasexceeded in occupied areas

D.D. No special precautions are necessary if SSB and CW No special precautions are necessary if SSB and CW are the only modes usedare the only modes used


G0A12 What precaution should you G0A12 What precaution should you take whenever you make adjustments take whenever you make adjustments or repairs to an antenna?or repairs to an antenna?

A.A. Ensure that you and the antenna structure are Ensure that you and the antenna structure are groundedgrounded

B.B. Turn off the transmitter and disconnect the feedlineTurn off the transmitter and disconnect the feedline

C.C. Wear a radiation badgeWear a radiation badge



G0A12 What precaution should you G0A12 What precaution should you take whenever you make adjustments take whenever you make adjustments or repairs to an antenna?or repairs to an antenna?

A.A. Ensure that you and the antenna structure are Ensure that you and the antenna structure are groundedgrounded

B.B. Turn off the transmitter and disconnect Turn off the transmitter and disconnect the feedlinethe feedline

C.C. Wear a radiation badgeWear a radiation badge



G0A13 What precaution should be G0A13 What precaution should be taken when installing a ground-taken when installing a ground-mounted antenna?mounted antenna?

A.A. It should not be installed higher than you can reachIt should not be installed higher than you can reach

B.B. It should not be installed in a wet areaIt should not be installed in a wet area

C.C. It should be painted so people or animals do not It should be painted so people or animals do not accidentally run into itaccidentally run into it

D.D. It should be installed so no one can be exposed to It should be installed so no one can be exposed to RF radiation in excess of maximum permissible RF radiation in excess of maximum permissible limitslimits


G0A13 What precaution should be G0A13 What precaution should be taken when installing a ground-taken when installing a ground-mounted antenna?mounted antenna?

A.A. It should not be installed higher than you can reachIt should not be installed higher than you can reach

B.B. It should not be installed in a wet areaIt should not be installed in a wet area

C.C. It should be painted so people or animals do not It should be painted so people or animals do not accidentally run into itaccidentally run into it

D.D. It should be installed so no one can be It should be installed so no one can be exposed to RF radiation in excess of maximum exposed to RF radiation in excess of maximum permissible limitspermissible limits


G0A14 What is one thing that can be G0A14 What is one thing that can be done if evaluation shows that a done if evaluation shows that a neighbor might receive more than the neighbor might receive more than the allowable limit of RF exposure from the allowable limit of RF exposure from the main lobe of a directional antenna?main lobe of a directional antenna?

A.A. Change from horizontal polarization to vertical Change from horizontal polarization to vertical polarizationpolarization

B.B. Change from horizontal polarization to circular Change from horizontal polarization to circular polarizationpolarization

C.C. Use an antenna with a higher front-to-back ratioUse an antenna with a higher front-to-back ratio

D.D. Take precautions to ensure that the antenna cannot Take precautions to ensure that the antenna cannot be pointed at their housebe pointed at their house


G0A14 What is one thing that can be G0A14 What is one thing that can be done if evaluation shows that a done if evaluation shows that a neighbor might receive more than the neighbor might receive more than the allowable limit of RF exposure from the allowable limit of RF exposure from the main lobe of a directional antenna?main lobe of a directional antenna?

A.A. Change from horizontal polarization to vertical Change from horizontal polarization to vertical polarizationpolarization

B.B. Change from horizontal polarization to circular Change from horizontal polarization to circular polarizationpolarization

C.C. Use an antenna with a higher front-to-back ratioUse an antenna with a higher front-to-back ratio

D.D. Take precautions to ensure that the Take precautions to ensure that the antenna cannot be pointed at their houseantenna cannot be pointed at their house


G0A15 How can you determine that G0A15 How can you determine that your station complies with FCC RF your station complies with FCC RF exposure regulations?exposure regulations?

A.A. By calculation based on FCC OET Bulletin 65By calculation based on FCC OET Bulletin 65

B.B. By calculation based on computer modelingBy calculation based on computer modeling

C.C. By measurement of field strength using calibrated By measurement of field strength using calibrated equipmentequipment



G0A15 How can you determine that G0A15 How can you determine that your station complies with FCC RF your station complies with FCC RF exposure regulations?exposure regulations?

A.A. By calculation based on FCC OET Bulletin 65By calculation based on FCC OET Bulletin 65

B.B. By calculation based on computer modelingBy calculation based on computer modeling

C.C. By measurement of field strength using calibrated By measurement of field strength using calibrated equipmentequipment



240 Volt House Power240 Volt House Power

G0B Safety in the ham shackG0B Safety in the ham shack

• Electrical shock and treatmentElectrical shock and treatment

• The most hazardous type of electrical energy is 60 The most hazardous type of electrical energy is 60 cycle Alternating Currentcycle Alternating Current

• The maximum amount of electrical current flow The maximum amount of electrical current flow through the human body that ca be tolerated safety through the human body that ca be tolerated safety is 50 microamperesis 50 microamperes

• Current through the heart can cause the heart to Current through the heart can cause the heart to stop pumping. Electrical shock can be lethalstop pumping. Electrical shock can be lethal


G0B Safety cont’dG0B Safety cont’d

• GroundingGrounding• Current flowing from the hot wire to ground will Current flowing from the hot wire to ground will

cause a Ground Fault Interrupter (GFCI) to cause a Ground Fault Interrupter (GFCI) to disconnect the 120 or 240 Volt AC line power to the disconnect the 120 or 240 Volt AC line power to the devicedevice

• The metal chassis of every item of station The metal chassis of every item of station equipment must be grounded (assuming the item equipment must be grounded (assuming the item has such a chassis) because it ensures that has such a chassis) because it ensures that hazardous voltages cannot appear on the chassishazardous voltages cannot appear on the chassis

• A good engineering practice for lightning protection A good engineering practice for lightning protection grounds is ensuring they are bonded together with grounds is ensuring they are bonded together with all other groundsall other grounds


G0B Grounding cont’dG0B Grounding cont’d

* * It is not safe to use soldered joints with the wires It is not safe to use soldered joints with the wires that connect the base of a tower to a system of that connect the base of a tower to a system of ground rods because a soldered joint will likely be ground rods because a soldered joint will likely be destroyed by the heat of a lightning strikedestroyed by the heat of a lightning strike

* A danger from lead-tin solder is Lead can * A danger from lead-tin solder is Lead can contaminate food if hands are not washed carefully contaminate food if hands are not washed carefully after handlingafter handling



• FusingFusing• A 15 ampere fuse or circuit breaker would be A 15 ampere fuse or circuit breaker would be

appropriate to use with a circuit that uses AWG appropriate to use with a circuit that uses AWG number 14 wiringnumber 14 wiring

• WiringWiring• Only the “hot” (black and red) wires in a four-Only the “hot” (black and red) wires in a four-

conductor line cord should be attached to fuses or conductor line cord should be attached to fuses or circuit breakers in a device operated from a 240-circuit breakers in a device operated from a 240-VAC single-phase sourceVAC single-phase source

• AWG number 12 is the minimum wire size that may AWG number 12 is the minimum wire size that may be safely used for a circuit that draws up to 20 be safely used for a circuit that draws up to 20 amperes of continuous currentamperes of continuous current



• InterlocksInterlocks• The purpose of a transmitter power supply interlock The purpose of a transmitter power supply interlock

is to ensure that dangerous voltages are removed if is to ensure that dangerous voltages are removed if the cabinet is openedthe cabinet is opened

• Antenna and tower safetyAntenna and tower safety• For safety when climbing on a tower using a safety For safety when climbing on a tower using a safety

belt or harness always attach the belt safety hock belt or harness always attach the belt safety hock to the belt “D” ring with the hook opening away to the belt “D” ring with the hook opening away from the towerfrom the tower

• Any person preparing to climb a tower that supports Any person preparing to climb a tower that supports electrically powered devices should make sure all electrically powered devices should make sure all circuits that supply power to the tower are locked circuits that supply power to the tower are locked out and taggedout and tagged



G0B01 Which wire(s) in a four-G0B01 Which wire(s) in a four-conductor line cord should be attached conductor line cord should be attached to fuses or circuit breakers in a device to fuses or circuit breakers in a device operated from a 240-VAC single-phase operated from a 240-VAC single-phase source?source?

A.A. Only the "hot" (black and red) wiresOnly the "hot" (black and red) wires

B.B. Only the "neutral" (white) wireOnly the "neutral" (white) wire

C.C. Only the ground (bare) wireOnly the ground (bare) wire

D.D. All wiresAll wires


G0B01 Which wire(s) in a four-G0B01 Which wire(s) in a four-conductor line cord should be attached conductor line cord should be attached to fuses or circuit breakers in a device to fuses or circuit breakers in a device operated from a 240-VAC single-phase operated from a 240-VAC single-phase source?source?

A.A. Only the "hot" (black and red) wiresOnly the "hot" (black and red) wiresB.B. Only the "neutral" (white) wireOnly the "neutral" (white) wire

C.C. Only the ground (bare) wireOnly the ground (bare) wire

D.D. All wiresAll wires


AWG Wire Gauges vs. Current CapacityAWG Wire Gauges vs. Current Capacity

Continuous-Duty Continuous-Duty Current Capacity (Amps) Current Capacity (Amps)

AWGAWG SingleSingle BundledBundledGaugeGauge WireWire Wire Wire 88 73 73 46 46 1010 55 55 33 33 1212 41 41 23 23 1414 32 32 17 17 1616 22 22 13 13 1818 16 16 10 10


G0B02 What is the minimum wire size G0B02 What is the minimum wire size that may be safely used for a circuit that may be safely used for a circuit that draws up to 20 amperes of that draws up to 20 amperes of continuous current?continuous current?

A.A. AWG number 20AWG number 20

B.B. AWG number 16AWG number 16

C.C. AWG number 12AWG number 12

D.D. AWG number 8AWG number 8


G0B02 What is the minimum wire size G0B02 What is the minimum wire size that may be safely used for a circuit that may be safely used for a circuit that draws up to 20 amperes of that draws up to 20 amperes of continuous current?continuous current?

A.A. AWG number 20AWG number 20

B.B. AWG number 16AWG number 16

C.C. AWG number 12AWG number 12D.D. AWG number 8AWG number 8


G0B03 Which size of fuse or circuit G0B03 Which size of fuse or circuit breaker would be appropriate to use breaker would be appropriate to use with a circuit that uses AWG number 14 with a circuit that uses AWG number 14 wiring?wiring?

A.A. 100 amperes100 amperes

B.B. 60 amperes60 amperes

C.C. 30 amperes30 amperes

D.D. 15 amperes15 amperes


G0B03 Which size of fuse or circuit G0B03 Which size of fuse or circuit breaker would be appropriate to use breaker would be appropriate to use with a circuit that uses AWG number 14 with a circuit that uses AWG number 14 wiring?wiring?

A.A. 100 amperes100 amperes

B.B. 60 amperes60 amperes

C.C. 30 amperes30 amperes



G0B04 What is the mechanism by which G0B04 What is the mechanism by which electrical shock can be lethal?electrical shock can be lethal?

A.A. Current through the heart can cause the heart to Current through the heart can cause the heart to stop pumpingstop pumping

B.B. A large voltage field can induce currents in the A large voltage field can induce currents in the brainbrain

C.C. Heating effects in major organs can cause organ Heating effects in major organs can cause organ failurefailure



G0B04 What is the mechanism by which G0B04 What is the mechanism by which electrical shock can be lethal?electrical shock can be lethal?

A.A. Current through the heart can cause the Current through the heart can cause the heart to stop pumpingheart to stop pumping

B.B. A large voltage field can induce currents in the A large voltage field can induce currents in the brainbrain

C.C. Heating effects in major organs can cause organ Heating effects in major organs can cause organ failurefailure



G0B05 Which of the following G0B05 Which of the following conditions will cause a Ground Fault conditions will cause a Ground Fault Circuit Interrupter (GFCI) to disconnect Circuit Interrupter (GFCI) to disconnect the 120 or 240 Volt AC line power to a the 120 or 240 Volt AC line power to a device?device?

A.A. Current flowing from the hot wire to the Current flowing from the hot wire to the neutral wireneutral wire

B.B. Current flowing from the hot wire to groundCurrent flowing from the hot wire to ground

C.C. Over-voltage on the hot wireOver-voltage on the hot wire



G0B05 Which of the following G0B05 Which of the following conditions will cause a Ground Fault conditions will cause a Ground Fault Circuit Interrupter (GFCI) to disconnect Circuit Interrupter (GFCI) to disconnect the 120 or 240 Volt AC line power to a the 120 or 240 Volt AC line power to a device?device?

A.A. Current flowing from the hot wire to the Current flowing from the hot wire to the neutral wireneutral wire

B.B. Current flowing from the hot wire to Current flowing from the hot wire to groundground

C.C. Over-voltage on the hot wireOver-voltage on the hot wire



G0B06 Why must the metal chassis of G0B06 Why must the metal chassis of every item of station equipment be every item of station equipment be grounded (assuming the item has such grounded (assuming the item has such a chassis)?a chassis)?

A.A. It prevents blowing of fuses in case of an internal It prevents blowing of fuses in case of an internal short circuitshort circuit

B.B. It provides a ground reference for the internal It provides a ground reference for the internal circuitrycircuitry

C.C. It ensures that the neutral wire is groundedIt ensures that the neutral wire is grounded

D.D. It ensures that hazardous voltages cannot appear It ensures that hazardous voltages cannot appear on the chassison the chassis


G0B06 Why must the metal chassis of G0B06 Why must the metal chassis of every item of station equipment be every item of station equipment be grounded (assuming the item has such grounded (assuming the item has such a chassis)?a chassis)?

A.A. It prevents blowing of fuses in case of an internal It prevents blowing of fuses in case of an internal short circuitshort circuit

B.B. It provides a ground reference for the internal It provides a ground reference for the internal circuitrycircuitry

C.C. It ensures that the neutral wire is groundedIt ensures that the neutral wire is grounded

D.D. It ensures that hazardous voltages cannot It ensures that hazardous voltages cannot appear on the chassisappear on the chassis


G0B07 Which of the following should be G0B07 Which of the following should be observed for safety when climbing on a observed for safety when climbing on a tower using a safety belt or harness?tower using a safety belt or harness?

A.A. Never lean back and rely on the belt alone to Never lean back and rely on the belt alone to support your weightsupport your weight

B.B. Always attach the belt safety hook to the belt "D" Always attach the belt safety hook to the belt "D" ring with the hook opening away from the towerring with the hook opening away from the tower

C.C. Ensure that all heavy tools are securely fastened to Ensure that all heavy tools are securely fastened to the belt D ringthe belt D ring

D.D. Make sure that your belt is grounded at all timesMake sure that your belt is grounded at all times


G0B07 Which of the following should be G0B07 Which of the following should be observed for safety when climbing on a observed for safety when climbing on a tower using a safety belt or harness?tower using a safety belt or harness?

A.A. Never lean back and rely on the belt alone to Never lean back and rely on the belt alone to support your weightsupport your weight

B.B. Always attach the belt safety hook to the Always attach the belt safety hook to the belt "D" ring with the hook opening away from belt "D" ring with the hook opening away from the towerthe tower

C.C. Ensure that all heavy tools are securely fastened to Ensure that all heavy tools are securely fastened to the belt D ringthe belt D ring

D.D. Make sure that your belt is grounded at all timesMake sure that your belt is grounded at all times


G0B08 What should be done by any G0B08 What should be done by any person preparing to climb a tower that person preparing to climb a tower that supports electrically powered devices?supports electrically powered devices?

A.A. Notify the electric company that a person will be Notify the electric company that a person will be working on the towerworking on the tower

B.B. Make sure all circuits that supply power to the Make sure all circuits that supply power to the tower are locked out and taggedtower are locked out and tagged

C.C. Ground the base of the towerGround the base of the tower

D.D. Disconnect the feed-line for every antenna at the Disconnect the feed-line for every antenna at the stationstation


G0B08 What should be done by any G0B08 What should be done by any person preparing to climb a tower that person preparing to climb a tower that supports electrically powered devices?supports electrically powered devices?

A.A. Notify the electric company that a person will be Notify the electric company that a person will be working on the towerworking on the tower

B.B. Make sure all circuits that supply power to Make sure all circuits that supply power to the tower are locked out and taggedthe tower are locked out and tagged

C.C. Ground the base of the towerGround the base of the tower

D.D. Disconnect the feed-line for every antenna at the Disconnect the feed-line for every antenna at the stationstation


G0B09 Why is it not safe to use G0B09 Why is it not safe to use soldered joints with the wires that soldered joints with the wires that connect the base of a tower to a connect the base of a tower to a system of ground rods?system of ground rods?

A.A. The resistance of solder is too highThe resistance of solder is too high

B.B. Solder flux will prevent a low conductivity Solder flux will prevent a low conductivity connectionconnection

C.C. Solder has too high a dielectric constant to provide Solder has too high a dielectric constant to provide adequate lightning protectionadequate lightning protection

D.D. A soldered joint will likely be destroyed by the heat A soldered joint will likely be destroyed by the heat of a lightning strikeof a lightning strike


G0B09 Why is it not safe to use G0B09 Why is it not safe to use soldered joints with the wires that soldered joints with the wires that connect the base of a tower to a connect the base of a tower to a system of ground rods?system of ground rods?

A.A. The resistance of solder is too highThe resistance of solder is too high

B.B. Solder flux will prevent a low conductivity Solder flux will prevent a low conductivity connectionconnection

C.C. Solder has too high a dielectric constant to provide Solder has too high a dielectric constant to provide adequate lightning protectionadequate lightning protection

D.D. A soldered joint will likely be destroyed by A soldered joint will likely be destroyed by the heat of a lightning strikethe heat of a lightning strike


G0B10 Which of the following is a G0B10 Which of the following is a danger from lead-tin solder?danger from lead-tin solder?

A.A. Lead can contaminate food if hands are not washed Lead can contaminate food if hands are not washed carefully after handlingcarefully after handling

B.B. High voltages can cause lead-tin solder to High voltages can cause lead-tin solder to disintegrate suddenlydisintegrate suddenly

C.C. Tin in the solder can "cold flow" causing shorts in Tin in the solder can "cold flow" causing shorts in the circuitthe circuit

D.D. RF energy can convert the lead into a poisonous gasRF energy can convert the lead into a poisonous gas


G0B10 Which of the following is a G0B10 Which of the following is a danger from lead-tin solder?danger from lead-tin solder?

A.A. Lead can contaminate food if hands are Lead can contaminate food if hands are not washed carefully after handlingnot washed carefully after handling

B.B. High voltages can cause lead-tin solder to High voltages can cause lead-tin solder to disintegrate suddenlydisintegrate suddenly

C.C. Tin in the solder can "cold flow" causing shorts in Tin in the solder can "cold flow" causing shorts in the circuitthe circuit

D.D. RF energy can convert the lead into a poisonous gasRF energy can convert the lead into a poisonous gas


G0B11 Which of the following is good G0B11 Which of the following is good engineering practice for lightning engineering practice for lightning protection grounds?protection grounds?

A.A. They must be bonded to all buried water and gas They must be bonded to all buried water and gas lineslines

B.B. Bends in ground wires must be made as close as Bends in ground wires must be made as close as possible to a right anglepossible to a right angle

C.C. Lightning grounds must be connected to all Lightning grounds must be connected to all ungrounded wiringungrounded wiring

D.D. They must be bonded together with all other They must be bonded together with all other groundsgrounds


G0B11 Which of the following is good G0B11 Which of the following is good engineering practice for lightning engineering practice for lightning protection grounds?protection grounds?

A.A. They must be bonded to all buried water and gas They must be bonded to all buried water and gas lineslines

B.B. Bends in ground wires must be made as close as Bends in ground wires must be made as close as possible to a right anglepossible to a right angle

C.C. Lightning grounds must be connected to all Lightning grounds must be connected to all ungrounded wiringungrounded wiring

D.D. They must be bonded together with all They must be bonded together with all other groundsother grounds


G0B12 What is the purpose of a G0B12 What is the purpose of a transmitter power supply interlock?transmitter power supply interlock?

A.A. To prevent unauthorized access to a transmitterTo prevent unauthorized access to a transmitter

B.B. To guarantee that you cannot accidentally transmit To guarantee that you cannot accidentally transmit out of bandout of band

C.C. To ensure that dangerous voltages are removed if To ensure that dangerous voltages are removed if the cabinet is openedthe cabinet is opened

D.D. To shut off the transmitter if too much current is To shut off the transmitter if too much current is drawndrawn


G0B12 What is the purpose of a G0B12 What is the purpose of a transmitter power supply interlock?transmitter power supply interlock?

A.A. To prevent unauthorized access to a transmitterTo prevent unauthorized access to a transmitter

B.B. To guarantee that you cannot accidentally transmit To guarantee that you cannot accidentally transmit out of bandout of band

C.C. To ensure that dangerous voltages are To ensure that dangerous voltages are removed if the cabinet is openedremoved if the cabinet is opened

D.D. To shut off the transmitter if too much current is To shut off the transmitter if too much current is drawndrawn


G0B13 Which of the following is the G0B13 Which of the following is the most hazardous type of electrical most hazardous type of electrical energy?energy?

A.A. Direct CurrentDirect Current

B.B. 60 cycle Alternating current60 cycle Alternating current

C.C. Radio FrequencyRadio Frequency



G0B13 Which of the following is the G0B13 Which of the following is the most hazardous type of electrical most hazardous type of electrical energy?energy?

A.A. Direct CurrentDirect Current

B.B. 60 cycle Alternating current60 cycle Alternating currentC.C. Radio FrequencyRadio Frequency



G0B14 What is the maximum amount of G0B14 What is the maximum amount of electrical current flow through the electrical current flow through the human body that can be tolerated human body that can be tolerated safely?safely?

A.A. 5 microamperes5 microamperes

B.B. 50 microamperes50 microamperes

C.C. 500 milliamperes500 milliamperes



G0B14 What is the maximum amount of G0B14 What is the maximum amount of electrical current flow through the electrical current flow through the human body that can be tolerated human body that can be tolerated safely?safely?

A.A. 5 microamperes5 microamperes

B.B. 50 microamperes50 microamperesC.C. 500 milliamperes500 milliamperes



G0 - ELECTRICAL AND RF SAFETY G0 - ELECTRICAL AND RF SAFETY [2 Exam Questions - 2 groups][2 Exam Questions - 2 groups]

Documents

Electrical and RF Safety 1 G0 - ELECTRICAL AND RF SAFETY [2 Exam Questions - 2 groups] G0ARF safety principles, rules and guidelines; routine station evaluation