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Sounds like an open trace. Hows' the AM regulator doing?

In the audio path - even the PA amp can get in the way.

One word, then cutoff, sounds like the Mic amp is turning on, but then shutting off, due to a TX switch issue, or a line is open - can't drain off a charge.

- check AMC and ALC control trim pots in the rear. TR34 for ALC and TR28 takes in that as well a AMC from the AM Regulator section and amplifies it to make the limiter work. Limiter is Tr27 - I'd pull that and if operation is normal - the ALC and AMC circuits need to be figured out and fixed...

ALC is SSB if left on due to bad parts, can "clip" the audio and force TR27 to clamp due to the control senses carrier too. Its' turned off by a diode (D41) from the AM mode side of that switch. IT equalizes or powers both sides of the ALC sense - rendering it unable to amplify anything.

Look at the TX section, and mid-section by network coils for shorts or broken traces.

You had a busted mic socket - there may be more twists and turns in this radio.

<blockquote data-quote="Handy Andy" data-source="post: 633355" data-attributes="member: 52309">Sounds like an open trace. Hows&#039; the AM regulator doing?In the audio path - even the PA amp can get in the way.One word, then cutoff, sounds like the Mic amp is turning on, but then shutting off, due to a TX switch issue, or a line is open - can&#039;t drain off a charge.&nbsp;- check AMC and ALC control trim pots in the&nbsp; rear. TR34 for ALC and TR28 takes in that as well a AMC from the AM Regulator section and amplifies it to make the limiter work. Limiter is Tr27 - I&#039;d pull that and if operation is normal - the ALC and AMC circuits need to be figured out and fixed...ALC is SSB if left on due to bad parts, can &quot;clip&quot; the audio and force TR27 to clamp due to the control senses carrier too. Its&#039; turned off by a diode (D41) from the AM mode side of that switch. IT equalizes or powers both sides of the ALC sense - rendering it unable to amplify anything.Look at the TX section, and mid-section by network coils for shorts or broken traces.You had a busted mic socket - there may be more twists and turns in this radio.</blockquote>

[QUOTE="Handy Andy, post: 633355, member: 52309"] Sounds like an open trace. Hows' the AM regulator doing? In the audio path - even the PA amp can get in the way. One word, then cutoff, sounds like the Mic amp is turning on, but then shutting off, due to a TX switch issue, or a line is open - can't drain off a charge. - check AMC and ALC control trim pots in the rear. TR34 for ALC and TR28 takes in that as well a AMC from the AM Regulator section and amplifies it to make the limiter work. Limiter is Tr27 - I'd pull that and if operation is normal - the ALC and AMC circuits need to be figured out and fixed... ALC is SSB if left on due to bad parts, can "clip" the audio and force TR27 to clamp due to the control senses carrier too. Its' turned off by a diode (D41) from the AM mode side of that switch. IT equalizes or powers both sides of the ALC sense - rendering it unable to amplify anything. Look at the TX section, and mid-section by network coils for shorts or broken traces. You had a busted mic socket - there may be more twists and turns in this radio. [/QUOTE]

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