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Old September 29th 09, 05:42 PM posted to rec.radio.amateur.antenna
Tim Shoppa Tim Shoppa is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 263
Default Open wire feedline

On Sep 29, 10:07*am, Cecil Moore wrote:
However, 50 feet of ladder-line is ~1/4WL. The low 80m feedpoint
impedance tends to be transformed to ~4k ohms. Most built-in
autotuners will not handle such impedances.


I personally think it's unlikely that even if someone is trapped by
the fancy-pants autotuner they bought, that they probably don't need
an extra fifty feet of line to deal with it. In my experience even ten
extra feet of line at 80M can noticeably change the matching taps I
use on my tuner if you're working in the 1/4 WL 65 foot feedline
range. Of course that extra ten feet might make their fancy pants
autotuner crap out on 20M, etc. and I can see how someone might start
feeling like the old lady that swallowed the fly. I would rewrite the
song to "swallowed the autotuner".

Tim N3QE