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AU-999 initial powerup, after restoration

I still have a low level buzzing in the phono channels, that sounds exactly like the buzz I was getting from the transformer before.

It is a bit worse on phono 1 than 2. But they both use the same circuit. Which might indicate a dirty switch/connection? I sprayed cleaner on all switches & worked them a bunch.

I'm wondering if it's a small ceramic cap on the head amp board, someone else here had one go with symptoms like that. Other than resistors those are the only stock parts left on the headamp board 1228-1.
 
Looking at lissenup's posts about the 1845's creating buzz in his phono. Hmm. Maybe I'll swap them for 1815's
 
I'll be damned: I subbed 1815's for the pair of 1845's on board 1228 & the phono is quiet now!!

The 1815's hFe are 147 ( matched )
The 1845's hFe were 420 or so

I wonder if the higher amplification was magnifying some circuit noise? If I crank it & listen carefully, I think I can barely hear it down there.

I have yet to bypass the phono 1,2, & aux wiring back to the VR pots at the back, that'll probably get the noise floor even lower.

Thanks @lissenup!!

Glad I listened up ;)
 
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