-----Original Message-----
From: Steve Katz <stevek@jmr.com>
To: 'alfredo@cln.it' <alfredo@cln.it>; amps@contesting.com
<amps@contesting.com>
To: <amps@contesting.com>
Date: 04 December 2001 00:14
Subject: RE: [AMPS] a question for the EXPERT
snip
>I don't know what you mean by a variable capacitor between the anode and
the
>antenna. How does that transform the high plate impedance of the tube to
>the low line impedance of the load?
Can't explain it succinctly without a smith chart, but it does work, and is
widely used on 2m and higher. It has the advantage over fixed link coupling
of fully variable and monotonic loading variation. A physically variable
link gives this as well, but a 'tuned' link might not.
Capacitor coupled output gives less harmonic suppression, but since you
should always include a harmonic filter between the amp and the antenna,
that's hardly significant.
Steve
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