Hi topBanders!
I live in an area about 10km away from a BC station that transmits on frequency
981khz and whose power is 200Kw. Whenever I had tried to take measurements with
a 160m antenna- with the latest equipment on the market- it was always
impossible. The equipment was always becoming an FSM. The addition of filters
given for this kind of projects did nothing. However, I did manage to solve the
problem once and for all by building a simple circuit with materials found in
almost every shack's junkbox.
The basic circuit was first introduced by W8CGD "Measurement of R+jx " in QST
June 1965 and was gradually improved throughout time.
I will refer to relative articles like the ones by G3HCT in Radcom, June 1979,
G3LDO "ARRL ANTENNA COMPENDIUM Vol 4, Vol 5" and lastly a wonderful project and
its software by SV1BYO which was based on the method of Five-Meter Method and a
Computer.
The whole set up consists of a power source (in my case, Elecraft K2- 1Watt), a
digital Voltmeter and a laptop on the base of my antenna. You insert the
measurements of the Voltmeter in the appropriate program boxes and you
immediately get the results on the measurements of R and jx of the antenna
without any interference by the BC station.
73
Manolis, SV1AOZ
_______________________________________________
Topband reflector - topband@contesting.com
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