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Old April 8th 04, 08:12 PM
Dave
 
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"Bob Myers" wrote in message
...

"Dave" wrote in message
...
One manufacturer of a similar "wind-up" antenna adds a capacitor to the

wire
in order to lower the resonance frequency of the wire. If I were going

to
try something similar (adding a capacitor, in series) in an attempt to

bring
the resonance of the wire down into the 30 MHz range, what size

(roughly)
capacitor should I use? Should I just try a few with different ranges,

or
does anyone here have any suggestions?


This isn't likely to help your basic problem, which appears
to be a lack of selectivity in the radio (in other words, it
is accepting signals over too wide a bandwidth, so you hear
not only the station you're interested in, but those "to either
side" as well. Having the passband too wide also makes
for more noise in general. There are filters that can be
added (within the receiver) to improve this, but your best
bet may be to simply look for a better receiver.

Bob M.




Hello Bob,

The selectivity doesn't actually seem to be too bad, as it is only the
weaker signals that I have trouble digging out of the hash and trash. It
does seem to be picking up some out-of-band signals, but they are very, very
weak. As I posted in another message, a 100 microhenry RF choke cut that
stuff out considerably, and I am planning on adding another 100 or 200
microhenry RF choke to see if that helps make the slightly stronger signals
a little more discernable. Next on the worksheet is an antenna tuner of
some sort.

Thanks all,

Dave