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Old January 29th 07, 01:41 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 1,614
Default Optimum length for ladder-fed dipole

Ian Jackson wrote:
Being serious, be aware that one of Cecil's 'fortes' is the avoidance of
tuning unit losses by using a particular length of feeder, so that the
antenna plus feeder system naturally presents a good match for the
transmitter. On a given frequency, every length of antenna has an
optimum length of feeder, so you need to switch in the appropriate
length of feeder for each band. There is a lot of debate about how much
power you lose an antenna tuner. You may, or may not, want to consider
using this technique.


It's also not an either/or choice. Without a tuner, the
ladder-line length selector needs to be able to be
varied in one foot increments from zero to 31 feet.

Since I bought my IC-756PRO with its built-in auto-
tuner, I only switch between three lengths of transmission
line and allow the autotuner to do the rest. So now I
have a hybrid system, still not requiring a full-range
antenna tuner.

I've submitted a magazine article to "Worldradio" magazine
about a dipole that works very well on 75m, 40m, and 17m
without a tuner and without changing feedline lengths.
--
73, Cecil http://www.w5dxp.com