Stuart.
I'd come to that conclusion as well, so I may try to move the feedpoint
further away from the window.
The rest of the loop is about 8ft higher than the guttering, but the actual
feedpoint sags downward by about 3ft due to the choke and co-ax.. The shack
end of the loop has a wide V shape to it, as the supports are about 3ft away
from the house itself.
It will be easy enough to get the shack end back in line with the supports,
or even to put the feedpoint even further away from the window by pushing it
away with another fishing pole.
I'll try it when I get some more of the poles, as it would make a good
catenary for the feeder.
Despite the problems on 1 or 2 bands, the rest of the bands appear to be
trouble free, and the antenna works well on 40m with no sign of any shack
RF.
My next thought is to try a true balanced tuner, with 2 rollercoasters and a
variable C on the feeder side fed with a choke balun on the TX side. Like
NT0Z's in QST April 2002 pp50 "A Balanced, Everyday Approach to All-Band
Bliss"
And finally, try and get the thing up higher. If my VHF / UHF experience is
anything to go by, height AGL is worth more than an amplifier or bigger
antenna..within reason of course!
Cheers.
Paul MW0CDO.
----- Original Message -----
From: "Stuart Rohre" <rohre@arlut.utexas.edu>
To: <tentec@contesting.com>
Sent: Monday, January 12, 2004 10:26 PM
Subject: Re: [TenTec] Not TT - Wire antenna question.
> Paul,
> with a loop 5 feet from the shack window, you likely will have RF in the
> shack no matter what balun you try. There is a 3 dimensional torus of
> radiation around the loop wire, and at the bands of HF, you are well
within
> the near field in your shack.
> -Stuart Rohre
> K5KVH
>
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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