On 10/08/2011 21:04, Kenneth Silverman wrote:
> <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 it improves your match, you also gain the advantage of having the
vertical grounded..thus giving you less static and noise to contend with
on receive.
Good luck, es vy 73
John EI7BA
> 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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