<SNIP> You could also try 10 or 12 turns of #12 or 14 gauge wire, 2" diam
across the feed point and ground.
Spread/compress the turns to get the lowest SWR/best match.
Just to be specific: this "hairpin" match only works if the antenna
feedpoint impedance is lower than 50 ohms, The hairpin is an up-tranformer
of impedance (low to high transformation) and thus works for typical short
verticals which often have very low impedances. If the ground system is
poor and the feedpoint happens to be above 50 ohms (indicating a lot of
ground loss), the hairpin will further increase the impedance and make the
SWR worse.
Kenny K2KW
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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