Dear Doc,
It's a niggling point but the PM3A has semi-break-in. Hi.
Now to your question. There is a small trimpot on the control board that
will adjust the hang-in time. If you have access to a scope you should look
at the timing voltages and see if any of the waveforms differ between 40 and
20 meter operation. Maybe some RF is getting in to the board on 40.
Let me know if you don't have a schematic. I can send you a copy of the
original and also of my mods to the control board. My PM3A has been in
pieces since 1980 but I got 8 great years out of it while it was my only
rig. Hi.
Tom Hamblin, sine HN
VA3HN, VE3TMH, VE3HIE
--__--__--
Message: 8
Reply-To: dock0evz@earthlink.net
From: "Doc K0EVZ" <dock0evz@earthlink.net>
To: "qrp-l reflector" <qrp-l@Lehigh.edu>,
"Ten-Tec Relector" <tentec@contesting.com>
Cc: "doc k0evz earthlink" <dock0evz@earthlink.net>
To: <tentec@contesting.com>
Date: Wed, 11 Dec 2002 17:51:27 -0600
Subject: [TenTec] Help with PM3A?
Gang:
Can anyone help with a Ten-Tec PM3A question? This newly acquired rig
seems to work FB on 20 metres = full break-in working, etc.
But on 40 metres it *doesn't* have the full QSK. Rig tunes up OK on 40,
listens good, etc. But there is no full break-in. Anyone know what might
need attention? Help...help....help!
73,
--Doc/K0EVZ
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