While I agree that in the REVERSE direction on 2 wire Beverages they
work OK with one wire open and one grounded, I cannot wrap my mind
around what the termination resistance is in the forward direction. The
reverse direction is resistively terminated into the receiver port but the
other direction is not terminated. Do they really work properly in the
forward direction or are they a compromise. What makes the forward
resistive termination on this resonant mode? My GUESS is they sorta
work in the forward direction because the ground connection is resistive
and not perfect. In the case of poor ground, the forward direction has a
compromise termination and the reverse direction does not get all the
reflected voltage. The worse the ground is, the better the forward
termination and the worse the reverse reflection. Compromise?
Until then transformers are cheap, easy, and I know they work.
Interestingly enough the RDF of a Beverage is only degraded on a
1Kft Beverage by about 2dB if the termination resistance is 50 ohms
instead of 400. This would make one think the antenna was working allright.
Front to back however is destroyed making one think it was not working
allright?
Hope someone here has a definitive answer.
Lee K7TJR OR
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