At 12:21 PM 10/20/98 +0000, Barry wrote:
>My guy wires are Phillystran, so no problems with interactions. I use
>copperweld wires for the elements, and use an Ameritron RCS-8V for
>switching (also have a 160 m antenna on this switchbox).
>>From personal experience, I found that when the wires are tuned for CW,
>they still load on 3800, but much of the directivity is lost. When
>tuned for 3800, the mismatch is too great on CW to load up the amp.
Hmmm, interesting. Both in the models and in real life, gain and
particularly directivity persist in my antenna, at least up to 3850. I've
had people tell me of seeing F/B ratios of as much as 50 dB on relatively
short hauls on SSB, which I think must be high-angle flukes. 15-20 dB
seems much more usual on DX.
On the other hand, only rarely is there a great difference between two
adjacent dipoles -- the nose of the pattern is so broad that F/S isn't
really very significant. Perhaps these differences reflect the difference
between 3 and 4 dipoles.
I'm intrigued by your using a regular switchbox. Doesn't the RCS8V ground
the unused antennas? Sounds like an entirely different situation than one
where both shield and center are floated at the switchbox. That could make
a difference, too, of course.
73, Pete Smith N4ZR
In wild, wonderful, only middlin' rare WEST Virginia
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