Last week I posted some questions about a shorty Beverage I was working on.
I would like to thank all those who responded, especially ON4UN and K9AY.
The consensus was interaction between the TX antenna system and the
Beverage. John, ON4UN, pointed to Figure 7-28 in his "Low Band DXing" book
as evidence. The arguments were/are very convincing and I don't disagree
with them. However, I am unable to prove interaction as I did with all the
other RX antennas I have constructed. To further muddy the waters, the
shorty actually works sometimes. It was the only antenna I was able to copy
(for 30 seconds) VP8GEO on last week.
In an effort to resolve this, I created an EZNEC model. To make a long
story short, I was unable to get the model to match what I had measured.
I'm sure that interaction is the problem, but am still unable to prove it
beyond all doubt.
I have put a short explanation, some data, and the EZNEC model file on my
web page for those who might like to take a look at it. It's all at:
http://home.earthlink.net/~w7iuv/w7iuv/bev2.htm
Please direct comments about the model, etc., to me directly and I'll
summarize here if it looks like it might be of further interest.
73,
Larry - W7IUV
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