----- Original Message -----
From: "Herbert Schoenbohm" <herbs@vitelcom.net>
Thanks for the EZNEC model John. Are the wires in your model sloping
down or straight as a 45 degree slope would tend to make them appear a
bit shorter?.
Yes, it was assuming 45 deg slope, and all 0.1 inch wire.
However, apparently John is using a 60ft versatower tower with 22ft 2in
diam pole on top which has different resonant frequency of course. Am not
experienced in tower modelling, have simply assumed 60ft x 8in diam and 22ft
2in diam. to estimate result. Re-running the model with this approximate
structure loaded by 4 x 35ft sloping wires now shows resonance of about
1830kHz.
Increasing the tophat wires to 45ft brings down the resonance to around
1.65MHz, but little gained on feed Z because of longer foldback lowering
effective height. Others may wish to comment on these results.
73
John G3PQA
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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