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Old December 8th 07, 05:36 PM posted to rec.radio.amateur.antenna
Dave Dave is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 797
Default How to match 190 +j140 to a 50 ohm source?

if you have an instrument that is good enough to read the impedance like
that just try experimental values... a foot of small coax is around 20pf,
unfortunately that is a significant fraction of a wavelength so it will act
more like an open stub than a pure capacitor. try just putting a foot in
parallel with the feedpoint and snipping it shorter a bit at a time to see
if it helps.


wrote in message
...
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?)

It's tempting to just throw a cap in there, but will a discrete
capacitor look as it should at 450 Mhz? Or should I make it out of a
transmission line?

I did not know that books documented the Z0 of single wire conductors,
I'll look into that, thanks. BTW what is the full title of the APRL?
I hear it often (I'm kind of a rookie)

THanks everyone