> On Thu, Mar 25, 2010 at 12:09 PM, Petr Ourednik <indians@xsmail.com> wrote:
>
>> Hi all,
>>
>> as I received just one reply from all of You it seems to be nightmare to
>> detune
>> properly this antenna isn't it?
>>
>> Even antenna's gurus are silent...? :)
>>
>> I will be glad to get any ideas as I tried a lot but my rx ant is
>> useless still.
>>
>> 73 - Petr, OK1RP
>>
>>
Peter,
I mentioned this before....but before detuning anything there should be
a comprehensive and accurate determination if there is actually any
noise contribution from the TX antenna. Some of the gurus have done
this but so far I have not seen any tips published. In fact there could
be a situation where earthing an antenna feed point could make things
worse. I would presume that if you placed an identical (temporary)
Beverage several wave lengths away from your current Beverage, you could
make some comparisons......but the issues of common mode pickup long
feedline pickup, unless mitigated, with W8JI's design line crackers
from DXE, or double toroid choke rings with an independent ground in
between, your tests might be inconclusive.
Herb, KV4FZ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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