To: <amps@contesting.com>
>> Date: Thu, 14 May 1998 01:21:12 -0800
>> From: Rich Measures <measures@vc.net>
>> Subject: Re: [AMPS] Re: Parasitics
>
>> >Rich claimed a K5 had parasitics in his 922 because "mistuning and
>> >misloading can not cause excess tank voltage or arcs. The K5 showed up
>> >and correct Rich, and said the nichrome Rich sent him was never
>> >installed. It turned out the cause of the arc was a bad gas discharge
>> >tube in his lightning arrester.
---------------
Interested in this embarrassment? See Will's archive for:
From: "David B. Holtkamp (K5KH)" <holtkamp@roadrunner.com>
Newsgroups: rec.radio.amateur.homebrew
Subject: Re: TL922 Arcing/Oscillating? Help with diagnosis?
To: <amps@contesting.com>
Date: 30 Nov 1996 22:48:48 GMT
--------------
>> Is a bad lightning arrestor breaking down the same thing as deliberate
>> mistuning?
>
>Yes, so far as the PA is concerned they are identical.
The bad lightning arrestor that arced was not in in PA. It was connected
in the coax that fed the antenna.
>That's why I
>said "mistuning or misloading".
>
>During a load fault, the PA is no longer properly matched to the
>load.
agreed, especially if there is an arc in the antenna tuner or an arc in a
lightning arrestor in the coax line that feeds the tuner.
>If, during the mismatched condition, impedance at the tank end
>of the tube rises. With a high Q resonant tank
However Pi-network tanks are not resonant at the operating freq. because
Pi-networks are two L-networks in series, and Pi-L network tanks are
three L-networks in series.
>...........
Rich...
R. L. Measures, 805-386-3734, AG6K
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