Orin, I found it!? R14 is burned.? Diagram says 100 Ohms, and it measures around 4k and is all blackened.
I imagine it didn't burn by itself so now I have to see what took it out.? I am guessing Q8 is shorted but it could be Q7.? And maybe CR7 and CR8.
Now I have something I can deal with.
Bob
On Thursday, April 2, 2020, 10:22:43 PM PDT, Orin Eman <orin.eman@...> wrote:
R12?? Both sides.
Looking like it's U2 at the moment..., with Q7, Q8 next in line.? If the main amplifier is working correctly, either side of the diodes should be pretty much the same.
24.50 and 24.04 on each side of the diodes.
On Thursday, April 2, 2020, 04:51:49 PM PDT, Orin Eman < orin.eman@...> wrote:
So, it's looking like the main amplifier.? We can look at U2's inputs by measuring both sides of CR4 or CR5 (they are in parallel).
They are above and to the right of TP5, close to J1; from below the right end of J1, L to R with J1 uppermost, the components are: CR4, CR5, U2, R11, C4, R12, R13
Then look at U2's output by measuring both sides of R12. ?(One side of R13 goes to TP4, the other to R12.)
U5 pin 2, 13, 14 read -22, -14, -22 V respectively
On Thursday, April 2, 2020, 03:55:41 PM PDT, Orin Eman < orin.eman@...> wrote:
Two should be -24V, the other should (I think) be close to TP3.? I suspect you'll find one a diode drop from TP4.
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