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Genesis – the Birth of Antennas
Copyright © 2004 Gene Hinkle All Rights Reserved
“Why and How Antenna Ideas are Conceived, Computer Simulated,
Constructed, and Born Into the Wild for Field Day”
PresenterGene Hinkle, K5PA, Austin, Texas
No need to take notes. This entire presentation available at www.k5pa.com
No need to take notes. This entire presentation available at www.k5pa.com
Copyright © 2004 Gene Hinkle All Rights Reserved
Dedications
Dr. John D. Kraus»W8JK» Silent Key, July 18, 2004
Les Moxon»G6XN» Silent Key, March 11, 2004
Moxon
Genesis – Birth of Antennas
Copyright © 2004 Gene Hinkle All Rights Reserved
Whydo it?
What do you need?
Genesis – Birth of Antennas
Copyright © 2004 Gene Hinkle All Rights Reserved
Great Outdoor Activities
Lots of FUN
Genesis – Birth of Antennas
Copyright © 2004 Gene Hinkle All Rights Reserved
Special Fishing Spool
Sling Shot Gear
Get the Antenna Up
Genesis – Birth of Antennas
Copyright © 2004 Gene Hinkle All Rights Reserved
PortableMasts
Battery Power Portable
Copyright © 2004 Gene Hinkle All Rights Reserved
Topics
Conceptual IdeasComputer ModelingConstructionField Day Usage Wide Band Dipole
Moxon BeamFlipbeam Array (FBA)Phased Dipole ArrayReel Antenna
Examples
Methods
Copyright © 2004 Gene Hinkle All Rights Reserved
Idea Evolution Creating Antenna Solutions
Wide Band DipoleMoxon BeamFlipbeam Array (FBA)
Phased Dipole ArrayReel Antenna
Copyright © 2004 Gene Hinkle All Rights Reserved
Wide Band Dipole
Multiple HF Bands
Easy to Match to Feedline
Fast Band Change
High Efficiency
Simple Design
Desirable Features
Copyright © 2004 Gene Hinkle All Rights Reserved
Wide Band DipoleConceptual Idea
Basic Dipole is Half Wavelength LongGreat for Fundamental and Odd Harmonics
λ/2
XMIT
EXAMPLES GOALS50 Ohm Z Match to Transmitter
Easy OperationRadiation Pattern Not Important
COAX
3.5 MHz – 10.5 MHz – 24.5 MHz7 MHz – 21 MHz
Copyright © 2004 Gene Hinkle All Rights Reserved
Wide Band DipoleConceptual Idea
ProblemsWide Band Operations are Difficult to AchieveCoax Losses at High VSWR
Do Not Make λ/2
ATU
FEATURESOff Resonance Operation
Need Antenna Tuner Unit (ATU)Keep at Antenna to Reduce Losses
TwinLead
XMITRF COAX
Control Line
Copyright © 2004 Gene Hinkle All Rights Reserved
Wide Band DipoleConstruction
4:1BALUN ATU
OUT INTackle Box ATU
Balanced or Unbalance Output Connections
Copyright © 2004 Gene Hinkle All Rights Reserved
Wide Band DipoleConstruction
Computer NetworkControl Cable with RJ-45’s
RF Coax Cable
Copyright © 2004 Gene Hinkle All Rights Reserved
Wide Band DipoleCenter Mast
Wires
AutomaticTuner Unit
Low LossLadder Line
Field Day Usage
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon Beam
Gain Over Dipole
Easy to Match to Feedline
Good Front-to-Back Ratio
High Efficiency
Simple Design Inexpensive
Small Size Can Be Rotated
Desirable Features
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamConceptual Idea
Reflector
DrivenElement
About 5%Longer Than
Driven Element
Basic 2-elementBeam
Take a 2-elementYagi Beam
And Create NewAntenna
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamConceptual Idea
Reflector
DrivenElement
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamConceptual Idea
Reflector
DrivenElement
Reflector
DrivenElement
About 5%Longer Than
Driven Element
Increased MutualCoupling.
Increased Current onElement Ends.
Elements Fold Back TowardsOne Another
Basic 2-elementBeam
Fold the Ends toCreate Moxon Beam
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamConceptual Idea
Reflector
DrivenElement
Reflector
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamModeling the Moxon
Reflector
DrivenElement
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamModeling Reality, Stressed
Moxon Bends Inward
The Reflector [4] Uses InsulatedWire – Dielectric LoadingShortens Effective Length
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamModeling
1.5
VSWR with 50 OhmSource Impedance
VSWR with 75 OhmSource Impedance
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Moxon BeamModeling
Azimuth Beam PatternElevation Beam Pattern
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Moxon BeamConstruction
Gap Spacer Rod
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Moxon BeamConstruction
Coax Line BALUNUnit
Driven ElementBeing Screwed to Mast Bracket
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamConstruction
Reflector ElementScrews to Side Rods
InsulatedWire
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon BeamField Day Usage
Field Day Tripod Mount6 Meter Moxon Beam
Stressed Moxon
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)
Gain Over Dipole
Easy to Match to Feedline
Good Front-to-Back Ratio
High Efficiency
Simple Design Inexpensive
Small Size Instant Rotation
Desirable Features
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Conceptual Idea
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Conceptual Idea
Length is Longer Lengths are Equal
DrivenElement
Reflector
DrivenElement
Reflector
FBA isSymmetrical
Moxon isAsymmetrical
So, Electrically, LengthenThe ReflectorBut... HOW?
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Modeling
MaximumRadiation
ReducedRadiation
Two Feed LinesOne for Power, The Other For Loading
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Modeling
MaximumRadiation
ReducedRadiation
Then Flip
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Modeling
Copyright © 2004 Gene Hinkle All Rights Reserved
AZ-EL Patterns
Azimuth Pattern Elevation Pattern
GreatFront-Back
Ratio
Main Lobe
Copyright © 2004 Gene Hinkle All Rights Reserved
VSWR Bandwidth Curves
Less than 2:1 VSWR Possible
Copyright © 2004 Gene Hinkle All Rights Reserved
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Construction
Copyright © 2004 Gene Hinkle All Rights Reserved
Dielectric Constant = 3.5Epoxy Material Fiber Glass
Thickness Wall Varied
50 MilThickness
100 MilThickness
Modeled Resonance ShiftWith Thickness
Copyright © 2004 Gene Hinkle All Rights Reserved
F (MHz)
SWR R (Ohms)
X (Ohms)
Diel C Thick (MIL)
18.8 1.24 41 3.5 3.5 100
19.3 1.3 38.8 3.15 3.5
3.5
19.5 1.33 37.7 2.18 3.5 37
1
19.4 1.32 38.6 4.36
50
40
020.1 1.43 36.3 6.5
Copyright © 2004 Gene Hinkle All Rights Reserved
37 MilThickness
650 KHzShift Matches
Real Life
Modeled Vs. Real Life
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)BALUN
1:1Test Measurements» Effect of Fiber
Glass Loading on Resonance
» Test Dipole» BALUN for
Balanced Feed Line
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Construction Techniques» Detuning Due to Fiber Glass Materials» Basic Dipole Element – Baseline
Fiberglass Fishing Poles, Wonderpole, Cut to 11' 6" Length Each Wire
Fo VSWR Rs Xs17.500 4.3 116 11917.750 3.7 67 9318.000 3.1 44 6518.250 2.6 37 4618.500 2.0 35 2918.750 1.6 37 1719.000 1.2 44 819.150 1.0 50 419.250 1.1 55 419.500 1.4 69 1219.750 1.8 69 3320.000 2.2 50 47
VSWR Without Fiberglass Pole as Element
1.0
1.5
2.0
2.5
3.0
17.0 17.5 18.0 18.5 19.0 19.5 20.0 20.5
Freq (MHz)
VSW
R
Z Measurement
52' 8.5" RG-58U Coax
Balun 1:1Wire endsWire ends
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Construction Techniques» Fiber Glass Lowers Resonant Frequency» Must Account for This in Final
DimensioningFiberglass Fishing Poles, Wonderpole, Cut to 11' 6" Length Each Wire
Fo VSWR Rs Xs17.500 2.0 67 4217.750 1.8 52 3418.000 1.6 44 2218.250 1.3 41 1118.500 1.2 43 718.750 1.3 52 1419.000 1.5 67 2019.250 1.9 88 2319.500 2.2 95 44
VSWR With Fiberglass Pole as Element
1.0
1.5
2.0
2.5
3.0
17.0 17.5 18.0 18.5 19.0 19.5 20.0
Freq (MHz)
VSW
R
Z Measurement
52' 8.5" RG-58U Coax
Balun 1:1Wire endsWire ends
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Construction Techniques» Overall Shift is -650KHz, So Make Antenna Shorter!
Resonance Shift Due to Fiberglass Pole
1.0
1.5
2.0
2.5
3.0
3.5
4.0
17.00 18.00 19.00 20.00
Frequency (MHz)
VSW
R Wire OnlyWire in Pole
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Construction Details Driven Element
Cross Arm Assembly
Driven ElementExit at End
Driven Element
Wonderpole™ by Shakespeare
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Construction
Driven ElementCross Arm Assembly
Mast to Boom Assembly BracketDX Engineering Product
Element to Boom Assembly BracketHome Depot Home Product
PVC PipeInsulator
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)ConstructionPhasing Harness with
Relay Box/Control Line
DPDT Relay with N.O. Contacts
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Construction
Driven Element Connectionto Side Wires
Phasing Harness Connectionto Driven Element from Mast
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Field Day Usage
Inspection ofRF Relay
Completed FBAUp 22 Feet
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)Evolutions» Greater Gain & F/B» Switched Beams
Reflector(make look inductive)Driven
Element
Director(make look capacitive)
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Array (FBA)
Director(make look capacitive)Driven
Element
Reflector(make look inductive)
Evolutions» Greater Gain & F/B» Switched Beams
Flip
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole Array
Gain Over Dipole
Easy to Match to Feedline
High Efficiency
Simple Design
Inexpensive
Desirable Features
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Start with the Basic Dipole Element
Half Wave LengthDipole Section
Transmitter
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole Array
Half Wave LengthDipole Section #1
Transmitter
Half Wave LengthDipole Section #3
Half Wave LengthDipole Section #2
Conceptual Idea» Add More Dipoles, Fields are Adding Broadside
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Notice Polarity of “Phasing” Between Elements
Half Wave LengthDipole Section #1
Transmitter
Half Wave LengthDipole Section #3
Half Wave LengthDipole Section #2 ++ +-- -
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Can’t Just Connect Wire Ends; Phasing Destroyed
Half Wave LengthDipole Section #1
Transmitter
Half Wave LengthDipole Section #3
Half Wave LengthDipole Section #2 ++ - --+
Must Have 180°Phase Reversal Here!
Must Have 180°Phase Reversal Here!
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Can Add Equivalent of 180° of Wire length; “Phasing Harness”
Half Wave LengthDipole Section #1
Transmitter
Half Wave LengthDipole Section #3
Half Wave LengthDipole Section #2 ++ + ---
Must Have 180°Phase Reversal Here!
Must Have 180°Phase Reversal Here!
Fields Due toAC Current Cancels;No Radiation From
Phasing Lines
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Repositioning of Phasing Line
Half Wave LengthDipole Section #1
Transmitter
Half Wave LengthDipole Section #3
Half Wave LengthDipole Section #2 ++ + ---
Must Have 180°Phase Reversal Here!
Must Have 180°Phase Reversal Here!
Phasing LinesCan Be At Angles.
Remember, No Radiation
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Further Repositioning of Phasing Line
Half Wave LengthDipole Section #1
Transmitter
Half Wave LengthDipole Section #3
Half Wave LengthDipole Section #2 ++ +-- -
Must Have 180°Phase Reversal Here!
Must Have 180°Phase Reversal Here!
Phasing LinesCan Be Up Close.
Remember, No Radiation
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Repositioning of Phasing Line
Half Wave LengthDipole Section #1
Transmitter
Half Wave LengthDipole Section #3
Half Wave LengthDipole Section #2 ++ + ---
Must Have 180°Phase Reversal Here!
Must Have 180°Phase Reversal Here!
Phasing LinesCan Be Wrapped Around – Like Coax!
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea
Also180º Phasing
Section
Half Wave LengthDipole Sections
Half Wave LengthDipole Section
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConceptual Idea» Conversion to Modeling» Overcoming NEC-2 Cores Limitations
180º PhasingSection
180º PhasingSection
Half Wave LengthDipole Section
Half Wave LengthDipole Section
Half Wave LengthDipole Section
300 Ohm ImpedanceRF Source
ElectricalHalf Wave Length
300 Ohm Feed Line
Phased Dipole Array
Copyright © 2004 Gene Hinkle All Rights Reserved
Modeling» Horizontal
Component
Phased Dipole Array
Copyright © 2004 Gene Hinkle All Rights Reserved
Modeling» Vert+Horz
Component» Skywave
Validity
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayModeling
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole Array
80 M 40 M 30 M 20 M 17 M 15 M 12 M 10 M
Modeling» Just Like Our Old Friend the Wide Band Dipole – Use a Tuner» Phasing Line Has Little Effect Off Frequency» Approximate Locations of Ham Bands Shown
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArraysEvolutions» Vertical Applications
– “Sleeve Antenna”» Better Low Angle Performance
Half Wave LengthDipole Section
(Cylindrical Tubing)
Quarter WaveLength Section
InsideElectricalConnection
Center TubeDoes Not Touch
Outer Tubing
Ground RadialsFeed Point Z
150 Ohms
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Dipole ArrayConstruction» Reel Makes Storage a Snap
BalancedFeed Line
WireEnds
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel Antennas
Easy to Unwind or Wind
Easy to Match to Feedline
High Efficiency
Simple Design
Inexpensive
Desirable Features
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConceptual Idea
Roll Up Onto a
Reel for Easy StorageAntenna Elements
Feed Line
Feed Line
Feed Line
Need to Isolate EndFrom Coax
Line!Feed Line
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasModeling» Elevation Pattern
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasModeling» VSWR
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConstruction» 3 Methods for
Isolation ResonantCoax L-C
Trap
Ferrite Bead RF ChokeCoaxial
RF Choke
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConstruction
Coax RF Choke
Active Dipole End
Coax Feed Line
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel Antennas
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasModeling» Inductance vs. Length
Coax Coil Inductance Vs. Length(RG-58 on 1-1/2" PVC Pipe)
0.02.04.06.08.0
10.012.014.016.0
0.00 2.00 4.00 6.00 8.00 10.00
Length (inches)
Indu
ctan
ce (u
H)
44 pF to Resonateat 14.2 MHz
Coil Only
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConstruction
Coil Only
Coax Capacitor
End 2 End 1
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConstruction
Completed CoaxL-C Trap
With CoaxConnectors Installed
Coax Capacitor with FinalLength for Resonance
Dipping to FindResonance
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasStub LengthTo CreateResonance
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasFinal Antenna VSWR
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConstruction
Coax L-C Trap
AntennaEnd
Feed Line
Method of VSWRAdjustment by
Wrapping CapacitorAround Antenna End
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConstruction
Upper Antenna16 ft. 6 in.
Lower Antenna16 ft. 6 in.
Resonant TrapIsolator
50 ohmTransmitter
Connection Here
EffectiveFeed Point
30 ft.Fiberglass
Mast
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel AntennasConstruction» Reel Really
Makes It EZ to Stow
Coax L-CTrap
Copyright © 2004 Gene Hinkle All Rights Reserved
Where to go for more into ...Reel Antennas» New Dipole Feeder- Tuned Feeder Yet!, A.F. Stahler, AA6AX, 73
Magazine, June 1978» RFD-1 and RFD-2: Resonant Feed-Line Dipoles, James Taylor, W2OZH,
QST, August 1991Wide Band Dipoles» Five Bands, No Tuner, Bill Wright, G0FAH, QST, June 1995
Phased Arrays» Antennas for All Applications, John Kraus and Ronald Marhefka,
McGraw Hill, 2002..» Collinear Phased Antennas for the HF Bands, Douglas Fouts, KI6QR,
QST, March 1989» The W5GI Mystery Antenna, John Basilotto, W5GI, CQ Magazine, July
2003.» An Invisible DX Aerial for 14 MHz, Del Arthur, G0DLN, International
Antenna Collection, RSGB, 2003, pp. 103-105.Moxon Antennas» HF Antennas for All Locations, Les Moxon, G6XN, 2nd Edition, Printed
2002.» Two-Element 40-Meter Switched Beam, Carrol Allen, AA2NN, The
ARRL Antenna Compendium, Vol. 6, 1999, pp. 23-25.
Copyright © 2004 Gene Hinkle All Rights Reserved
Where to go for more into ...Antenna Modeling & Software» ARRL Antenna Modeling Course, L.B. Cebik, edited by Dean
Straw, American Radio Relay League, 2002.
» EZNEC or EZNEC+, Version 4.0.0, Roy Lewallen, www.eznec.com/
» MultiNEC, Version 2.2.1, Dan Maguire, AC6LA, www.qsl.net/ac6la/multinec.html
Antenna Modeling Software, Shareware» 4NEC2,
http://www.qsl.net/wb6tpu/swindex.html
» MMANA, by JE3HHT (Mininec derivative), http://www.qsl.net/mmhamsoft/mmana/
Copyright © 2004 Gene Hinkle All Rights Reserved
Thanks for Being a Great Audience ...
See You in the Field
You can download this presentation atwww.k5pa.com
Thanks for Being a Great Audience ...
See You in the Field
You can download this presentation atwww.k5pa.com
End Slide
Copyright © 2004 Gene Hinkle All Rights Reserved
Wide Band Dipole - Show ‘n Tell
Remote ATULadder Line
Copyright © 2004 Gene Hinkle All Rights Reserved
Moxon - Show ‘n Tell6 M Moxon Beam Pieces
Copyright © 2004 Gene Hinkle All Rights Reserved
Flipbeam Ant - Show ‘n TellAntenna Flip Switch ControlFlip Switch Ant RelayAntenna SwitchDipole Element Collapsed
Phasing Harness
Copyright © 2004 Gene Hinkle All Rights Reserved
Phased Array - Show ‘n Tell20 M Phased Dipoles with Reel
Copyright © 2004 Gene Hinkle All Rights Reserved
Reel Antenna - Show ‘n Tell