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Old December 8th 07, 06:41 PM posted to rec.radio.amateur.antenna
[email protected] s.g.hatch@gmail.com is offline
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First recorded activity by RadioBanter: Nov 2007
Posts: 11
Default How to match 190 +j140 to a 50 ohm source?

On Dec 8, 1:06 pm, Richard Clark wrote:
On Sat, 8 Dec 2007 09:24:30 -0800 (PST), wrote:
trombone section looks a little out of my league. I'm kind of in a
hurry. It's kind of too late to gamma match I think because I've
already soldered a connector onto the end of the antenna (its helical,
so i can't just reach in there and fool with it much, you know?)


To put it mildly, you are in a world of hurt.

As Dave points out elsewhere, if you have the instrumentation to
measure to the implied accuracy (or at least resolution) as is
suggested in this subject line; then you should cut-and-try.

As for capacitors, don't even think of anything but surface mount. But
where? You are back into that world of hurt if you don't have the
time to do it right (a simple gamma match).

It could be as easy, however, as crushing or spreading the first
couple of turns of the helix, or playing with the proximity of the
ground plane, or both. If you don't have time, then you certainly
shouldn't be playing with caps.

73's
Richard Clark, KB7QHC


Ok. again I'm not that experienced. What exactly is a gamma match?