Theory:
This antenna is a simple vertical ground plane made from swaged aluminum poles from a dining canopy set. Depending on the number of sections, it can be tuned on any frequency from 20m and 6m. A coil at the base allows 40m operation as well.
Advantages:
• excellent on-air performance
• low radiation angle good for DX
• no lossy transformer required = efficient
• easy to build with commonly available materials
Setup:
The coil has a 3/8-24 threaded base. Use a spike mount, jaw clamp, or sturdy tripod for this antenna.
The antenna should be approximately a quarter wavelength (¼λ) calculated via 234/MHz = length in feet). Example: 234 / 28.400 = 8.24 feet (8 feet 3 inches) for the center of the 10m Technician band. Add tent pole sections to get just under the desired length. Then, use the adjustable stinger for fine tuning. Your final tuned length may vary from the calculation.
This antenna requires 2 to 6 radials for decent performance depending on ground/soil conditions. Check out my FREE radials!
coil jumper removed for 40m
radial sets clipped to coax connector
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