Theory:
This antenna is based on K7MEM's Short Dipole Calculator covering 20m without coils, 40m with coils shorted, 75m w/coils inline. 15m is possible with a tuner via 40m harmonic.
Advantages:
• excellent on-air performance
• inexpensive
• half the size of 75m dipole
Coils:
• wound on small plastic bottles
• 2.575" dia x 1.725" long x 23 turns
• approx 30 μH
Construction:
• 18-gage wire from Home Depot for QRO @ 25-100 watts
• ring terminals simplify construction with nuts & bolts
• set up as inverted-V for omnidirectional propagation
An analyzer will make tuning easy and precise, but you can use the SWR meter in your rig if you don’t have one.
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