Hi Steve.
You are 100 % right, the V works like a top hat for a vertical TX antenna.
I it simple to detune any vertical TX antenna. Vertical TX antenna is the only
way to work DX on topband!
You may ask about the inverted V or low dipole, they are not 100% horizontal,
actually they are 50% horizontal on the broadside and 50% vertical along the
wire.
Ground reflects horizontal signals -1, it means 180 degree out of phase, and
the reflected signal cancels the arriving signal, The Arriving signal is
maximum only near 1 1/2 wave high above ground 750ft!!!.
The vertical reflected signal has +1 and add to the arriving signal producing
gain, ground gain.
Detuning a TX antenna is like a LC circuit, you need high impedance between the
antenna and the ground. The UNIPOLE or cage antenna works very well to detune
grounded towers up to 30 db, and it is easy to feed with 200 ohms, becoming a
very large broadband antenna. Isolated towers or inverted V is the same, they
need high isolation from ground.
I sed the same configuration for over 20 years, the open line works very well
80 - 10m.
Regards
JC
M4IS
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