Topband: K9AY minimum spacing from TX

[Mike Furrey]

 Well, on a small suburban lot with TALL pine trees (four and a large sweet gum tree in a square of 50 x60 feet), I had an inverted L with one L shaped elevated radial on the perimeter of the lot. One leg of the K9AY loop was about 6' away from the elevated radial. On receive I switched in an inductor to de-tune the transmit antenna to keep noise from being re-radiated to the loop. 

Now on transmit, a resistor burned up in the relay box. I added the same resistance except about 20 watts worth of dissipation and that took care of that problem. I used no more than 600 watts output in the Houston area.

I did notice some directivity problems with the loop with the proximity of the wire and trees but still the signal to noise ratio was improved enough to work what I could not hear the the vertical. 

When living in TN I had a larger lot and used a top loaded vertical and the K9AY loop is about 50 feet from the transmit antenna and the loop seems to show better directivity.I do not worry much about signal directivity but noticed that I have better results when I orient the loop to null the noise.

I hope this helps. 73, Mike WA5POK



    On Thursday, December 7, 2023 at 04:52:29 AM EST, Ashraf Chaabane <ash.kf5eyy at gmail.com> wrote:  
 
 Hi All,

How far should a K9AY be spaced from resonant antenna? I presume there is
no impact from nearby trees.

Please advise.
-- 
Ash ~ 3V8SS/KF5EYY
http://www.kf5eyy.info/
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