At 02:48 PM 3/6/98 +0000, Tom Rauch wrote:
>
>I have a Beverage that ends over 200 feet from the closest element
>of my four square array. I can actually watch signals change level on
>that Beverage while I switch the four square, and there is NO
>problematic coupling between those antennas other than via the
>"spatial" coupling between them. Even so, there is a degradation in
>S/N ratio at times without a noise increase, because the desired
>SIGNAL sometimes drops slightly when I fire the four square into the
>Beverages direction!
>
>ON4UN offered an excellent "rule of thumb". The best way to insure
>you won't have a problem is to not set yourself up for trouble (if
>you can avoid it). Why depend on luck unless we have to?
>
>
Let me add some more fuel to this fire and simply report that I had
an experience similar to Tom's with my first Beverage installation
which passed within 50 feet of my phased verticals. The Beverage
never produced the F/B that I thought it should. Then, one day, I
discovered, as Tom did, that I could make certain signals received
on the Beverage jump up or down in signal strength by switching
directions on the verticals. The effect was not observed on all signals,
however, and I could not deduce a pattern as to what caused only
particular signals to be affected and not others.
In any case, the solution was simply to move the Beverage 150 feet
away from the transmit antenna. The F/B, which was previously
deficient, improved dramatically.
Based on my experience, I would concur with the advice that
avoidance of potential problems, where possible, is the best strategy.
73, John W1FV
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