another HRD

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Andy Le Blanc
Posts: 2582
Joined: Sat Dec 22, 2007 1:16 am
Location: central Maine

another HRD

Post by Andy Le Blanc »

Just had a fender across the bench with a bad resistor.... AGAIN...
But this one was in an odd place, r28 47k, which feeds the buffer amp to the
preamp out. Its the top of a resistance divider, below is a 2.7k to ground.
The top of this resistance to ground is also the source for the power amp in
jack and the re-verb drive.

The symptom was early distortion, and an over-driven reverb...

None of which was tube related... The distortion was not the same as
having a bad r66 1r, at the bias test point, the current shunts through cr3
and is a much more subtle.

It looks like it might be a good target in the circuit for mods.
The pre out buffer might be good to REALLY drive a tube stage.
there's even a jack to make it foot switchable.
lazymaryamps
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