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Old May 2nd 09, 02:37 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default Resonance and equilibrium

On May 2, 6:24*am, "Dave" wrote:
"JIMMIE" wrote in message

...
On May 1, 7:37 pm, "Dave" wrote:

I dont know if Dave built it or not but I did and tested the beamwidth
just as you said and got 360 degrees. Rotating it had no effect at all
on signal strength. I tried it on 2M and couldnt hit the local
repeater with 1 watt normally I can reach it with 100mW. I would say
this classifies the antenna as a dummy load.


no, i am waiting for the final tweaked design. *if you have built one to
art's specs then you are probably measuring just the side/back lobes, which
is a very good sign. *if it has a pencil beam on 160m, then by the time it
gets to 2m the beam will probably be so thin that it will be like a laser
beam, so you'll have to be pointing it VERY accurately on the repeater. *so
go rotate it again, very slowly and carefully, and don't forget to aim it in
elevation also!


Hold on. I don.t know if I have a pencil beam as I can't measure it or
model it.
However, I don't see that as a real hurdle! The idea that the beam
width changes with frequency is beyond my ken. As for a final tweaked
design, for a ham that is an impossibility