Message-ID: <001a01bf1e70$b6eb2f20$342e63c3@default>
From: "Alan Melia" <Alan.Melia@btinternet.com>
To: "rsgb_lf_group" <rsgb_lf_group@blacksheep.org>
Subject: LF: re Datong converter problems
Date: Sun, 24 Oct 1999 23:22:23 +0100
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It looks like Roger has found a design problem that could affect other
converters. I have asked that he post any response from David Tong.

 I think the solution may be to reduce the crystal excitation, so the loop
gain in the oscillator becomes degenerative at the fundamental frequency. As
a quick check I find that the 3rd overtone is usually about 30 to 40 kHz
lower than 3 times the fundamental. If a fundamental oscillator is running
'cleanly' you should not be able to hear anything on a receiver tuned to the
fundamental and coupled loosly to the oscillator.

 I wonder it this will remove all those signals we just cant quite hear, but
I always think and sending CQ at 25wpm!! Strange I can never quite copy a
callsign.

Cheers de Alan G3NYK
Alan.Melia@btinternet.com