Posted this message last year after a similar request:
When we started flying GELSA in Lakeland we had a similar problem, reception
OK but poor & intermittent transmit & yes it was an antenna problem -
clearly the antenna is required to handle much greater power for
transmitting.
We replaced the existing welding rods with copper tape in the fin close out
but were unable to obtain any ferrite torroids. I therefore made up a
"balun" from a loop of the RG58 cable from a published design which should
be available on the net somewhere. Goodness knows how this works but after
trimming the copper tape there was a sudden dramatic reduction in VSWR
reading and our radio performance was transformed.
It worked for us, just don't ask me why!
Ours was a Terra also. The original antenna had no torroids. I don't know much
theory but believe that the antenna does know the difference between reception
& transmission because of the massive difference in power involved. Balun design
is available from Bob Archer. I'm fitting one of his antennas which are well
proven!
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request:
similar problem, reception
it was an antenna problem -
greater power for
transmitting.
tape in the fin close out
therefore made up a
design which should
this works but after
reduction in VSWR
transformed.
why!
fitting one of his antennas which are well proven!
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