1. VE3KL Selecting a Portable HF Antenna
Basic Issues
Ease of operation: Mechanical Design(weight ..
Efficiency…minimum gain around – 3dBi a goal.
Antenna patterns.. Some are quite directive
Ease of matching…. Very important
Transmission Line Losses
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
4nec2 Simulator
Sotabeams Trap
David Conn VE3KL
12/1/2018

2. Presentation Outline Problem Definition Typical Portable Antennas
Transmission Line Types…How to select
Case Studies
Conclusion
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
James Clerk Maxwell
Georg Simon Ohm

3. Types of Portable Operation
Summits On The Air (SOTA). Extreme
Pedestrian Portable. Very specialized
Casual outings in a park
Weekend camping…….. Dual band plus VHF
Field Day… More serious…need performance
Portable Operation from a vehicle..
…..
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

4. Antenna Classification (for spotting good DX designs, not NVIS)
Big antennas that are mounted well off the ground: ≥ λ/ High Gain at 30 Deg Elevation
Small and/or near ground antennas Low Gain at 30 Deg Elevation
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
12/1/2018

5. Antenna Classification (Base Numbers…
Antenna Classification (Base Numbers….No Losses, Perfect Ground) 30 Degree Elevation Angle
Halfwave Dipole, 14 MHz, 30 deg.elev m High, Horizontal dBi Max Gain
Vertical Antennas, Length ≤ λ/ dBi Max Gain
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
12/1/2018

6. Typical Antenna 30, 17 Metres Trapped Inverted V Performance?
Mini Toroid Trap
VE3KL Design
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

7. Antenna Photo Collage Source SOTA/Hfpack
Diamond
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
12/1/2018

8. Some Antenna Candidates
Inverted V…. Monoband
Trapped Inverted V…. Multi band
Inverted L … Monoband with One Radial (SOTA)
Quarter Wave Ground Plane… four radials above ground
Rotating monoband dipole
Pedestrian Vertical…one insulated radial
Random Wire, End Fed, Small/Big Loops, Diamond
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

9. Some Antenna Candidates Diamond Shape
Apex Angle
Trap or Loading Coil
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Base near ground
David Conn VE3KL
12/1/2018

10. System Simulation Includes
Cable Skin Effect
Cable Dielectric Loss
Cable Internal and External Inductance
Cable DC Resistance
Cable Velocity Factor
Antenna Wire Loss (Copper or Al)
Antenna Wire Insulation ( Dielectric, not losses)
Antenna Ground Type (Average)
Trap and Loading Coil Loss..Q = 100 for all cases
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

11. Transmission Line Selection
Loss not too important (Short Lines Used)
Light weight
Easy to use
Coax preferred…. Open wire hard to use
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

12. Transmission Line Selection
RG-8X 10 m long dB Loss
14 MHz (Belden 9258) Recommended
RG-58U 10m long 0.5 dB Loss
14 MHz (Belden 8219) Recommended
Transmission Line Selection
Approx Skin Effect Limited
0.1 MHz and above
Skin Effect Limited
1 MHz and above
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

13. Transmission Line Selection
RG174 U 10 m long dB Loss
14 MHz (Belden 7805) OK ???
RG174 U 10m long 1.1 dB Loss
14 MHz (Belden 8216) Poor
Transmission Line Selection
Skin Effect Limited
1 MHz and above
Skin Effect Limited
1 MHz and above
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Approx Skin Depth Limited
Above 20 MHz
Very High Loss at 100 MHz

14. Case Studies Full Size Dipole..20 Metres
Trapped Inverted V...30 and 17 Metres
Sota Inverted L...20 Metres
Hamstick/Buddipole Type Dipole...20 Metres
Vertical Diamond...20 Metres
Pedestrian Vertical...20 Metres
Short Vertical_Four Low Radials...20 Metres
12/1/2018
David Conn VE3KL

15. Case Study #1 Full Size Dipole 14 MHz Just Manageable in Moderate Wind
Al Tubing
Height = 7 metres
AL Telescoping Tubing
Light Balun 1:1 at top
Light mast: guy ropes
RG8X 0.4 dB loss
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Radio
Average Ground

16. Full Size Dipole H = 7 metres Gain = 5
Full Size Dipole H = 7 metres Gain = 5.1 deg BW = 1 MHz Very Good Not an SOTA Antenna.....Great for Field Day
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

17. Case Study #2 30,17 Metre Trapped Inverted V
18 MHz Trap
Ferrite Choke
6 Sections
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
T 50-6 Powdered Iron
Toroid 22 Turns 30 pF
12/1/2018

18. Polar Pattern. Elevation Gain @ 10 MHz= 1
Polar Pattern..Elevation 10 MHz= 1.8 dBi 17 and 30 metres, Height = 7 metres
Broadside 90deg
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

19. Gain @ 18 MHz = 4.3 dBi 17 and 30 metres, Height = 7 metres
Broadside 90deg
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

20. Trapped Inverted V 4nec2 Simulation Frequency Response
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

21. Measured Frequency Response AIM 4170 Vector Meter Tuned Slightly Low (Both Bands)
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
David Conn VE3KL
12/1/2018

22. Case Study #3
SOTA Antenna: Inverted L with one Insulated Radial 20 and 40 metres with tuner
Top
Light weight
Height = 10 metres
Top = 8.6 metres
Lradial = 3.0 metres
Radial Height = 0.5 metres
Wire gage #16 Copper
4:1 Balun
Light mast: guy ropes
Height
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Radial
4:1 Balun
Radio
Feed Point

23. Inverted L One Short Radial Optimized for 20 and 40 metres Gain (14 MHz) at 30 deg = 4.0 dBi….Good
Broadside Radiation
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

24. Inverted L One Short Radial Optimized for 20 and 40 metres Gain (7 MHz) at 30 deg = -1.0 dBi….OK
End Fire Radiation
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

25. Inverted L One Short Radial Frequency Response Good SWR Z0 = 200 Ω
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Broadside Radiation

26. Case #4 Buddipole/Hamstick Like Antenna Small Dipole with Loading Coil Good Field Day Back Up on 20 metres Poor Choice for 40 or 80 metres
Length = 4.9 m
Height = 3.5 m
Lcoil = 10 uH
Q = 100
Average ground
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

27. 14 MHz Buddipole/Hamstick Type Dipole on a Tripod Two Loading Coils Bandwidth = 0.2 MHz Gain = Deg
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Broad Side Radiation
Azimuth = 0 deg

28. Buddipole Type Dipole on a Tripod Two Loading Coils Bandwidth = 0
Buddipole Type Dipole on a Tripod Two Loading Coils Bandwidth = 0.2 MHz Might Need A Tuner 14 MHz
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

29. Case Study #5 Vertical Diamond Optimized for 50 Ω Input Impedance
Apex Angle
14 MHz
L = 4.6 m
Lcoil = 3 uH
Base Height = 1.0 m
Apex Angle = 56 deg
Total Height = 8.1 m
(Use a slightly bigger coil)
Loading Coil
Or Trap
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Increasing Lcoil
Reduces L and Lowers Gain :Still Matched

30. Vertical Diamond Four Loading Coils Gain = 3.4 dBi
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

31. Case Study #6 Pedestrian Vertical with Loading Coil One Trailing Radial (long or short)
Height = 2.0 Metres
Radial Height = 0.05 Metres
Coil Q = 100
Copper Wires
East
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Walking or Cycling West
Radiating East

32. Pedestrian Vertical Long Radial BW = 0
Pedestrian Vertical Long Radial BW = 0.4 MHz Lcoil = 14 uH Lradial = 4 metres Gain = -6.6 dBi
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
High Directivity but low gain
Long Radial

33. Pedestrian Vertical with Loading Coil One Trailing Radial: Length = 1 Metre Gain = -11 dBi BW = 0.2 MHz
Lcoil = 20 uH
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Short or no Radial
Bicycle frame acts as a
counterpoise

34. Case Study #7 Short Vertical, Loading Coil, Four Radials Close to Ground
Height = 3.0 Metres
Radial Length = 1.05 Metres
Radial Height = 0.05 Metres
Lcoil = 10 uH, Q = 100
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

35. Gain = deg Elevation Zin close to 50 Ohms due to losses Does not meet minimum Gain of -3dBi {best to use PSK31}
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

36. Case Study #8 End Fed One Wavelength 14 MHz
7 Metres High
Length = 18.7 Metres
Height 7 Metres at Far End
Feed Point 1 Metre High
Feed Point Impedance 1900 Ω
Counter Poise 1.5 Metres Long
Far End
Feed Point
Max Current High Off Gnd
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
Transformer
1900:50 Ω
Radio
Counter Poise
Average Ground

37. End Fed One Wavelength Transformer Matched 14 MHz Gain = 2
End Fed One Wavelength Transformer Matched 14 MHz Gain = deg Azimuth
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits

38. Recommended Antennas Full Sized Dipole, Inverted V, Diamond
End Fed, Trapped Inverted V
Low, small Dipole with loading coils
Pedestrian (walking or bicycle)…very low gain
Small Vertical with four radials…use a small dipole
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
73 Dave VE3KL

39. Summary See my 4nec2 files on ve3kl.com for all details
Maxwell & Ohm give insight
Simulators crunch numbers
Only eight case studies given….many more
Really short antennas are inefficient
All reasonable portable antennas are fun to use
A method that you can use easily to evaluate your own noise environment
A method that you can use to evaluate the quality of the ionosphere at any give time.
Some methods to control received noise
The Shannon Hartley limits
73 Dave VE3KL