This is a follow up to yesterdays message from Zack who is one of the Lab
Rats at the ARRL.
Altho TR-751 specific it may prompt a few to dig out their service
manuals for "real" radios and investigate.
It might save a few expensive amp tubes.
73......Carl KM1H
--------- Begin forwarded message ----------
From: "Zack Lau" <vhfl-list@arrl.org>
>From reports I've gotten, this seems to be a common problem.
I think I figured out what is causing it--the ALC circuitry
is run off the keyed transmit voltage (9T). Thus, when you
let off the mic button the keyed voltage drops, upsetting
the ALC. I'm not sure how this interacts with CW
waveshaping.--Zack W1VT
--------- End forwarded message ----------
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