For those of you interested in manufactured tuners check out March 97 QST or
their web site for reviews of 4 legal limit tuners. High end and low end are
represented.
Power handling, loss, heating, and matching abilities are shown. Some of it
is very surprising.
73 Steve wd0ct
----- Original Message -----
From: "Paul Christensen" <paulc@mediaone.net>
To: <amps@contesting.com>
Sent: Wednesday, June 20, 2001 3:48 PM
Subject: Re: [AMPS] Review of antenna tuner from Dayton
>
> > I'm amazed so many people buy tuners instead of building them, or
> > using stubs.
> > 73, Tom W8JI
>
> One of the simplest, practical, and cost-effective solutions to those who
> use open feeder/ladder line with multi-band antennas is the approach
> re-introduced by Cecil, W6RCA. Cecil has been an advocate of changing
> transmission line length in order to achieve a reasonably close 50-ohm
> transmitter match into the transmission line. I believe the concept of
> changing the length of one's transmission line to vary the antenna
system's
> input impedance can be traced back to the early '30s when link-coupling
was
> popular. Since the matching range of the link network was oftentimes
> limited, varying the length of the line was a solution to bring the
system's
> impedance within the range of the link.
>
> By Goodman's "My Transmission Line Really Does Tune my Antenna" does a
great
> job of explaining the differences on the effect of line impedance as a
> function of transmission line length. I believe the article was first
> published in a 1950s QST and has been re-printed periodically since then.
I
> wish they would print it every year.
>
> Anyway, Cecil's method of varying line length with relays is simple and
> effective. You can read more about it here...
>
> http://people.delphi.com/cecilmoore/mystery.htm
>
> -Paul, W9AC
>
>
>
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>
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