Phonoland

I think I should resolve the 26V dc LED being out. What is the easiest place to test to see if I have 26V DC? I do have the circuit diagram.

Where ever the schematic says it goes ?
Ron Rich

The schematic hasn't spoken to me and I'm not very proficient at reading a schematic. It looks to me I can test the AC voltages at the 6 input pins and at the 12 pin output connector on the 54875 rectifier card. Do you agree?

Sorry,
I can't read it either-- as I do not have it--hopefully someone else can chime in ?? Ron Rich

I've checked the input voltages to the rectifier PCB and they are ok. Some outputs are ok, some are not. Here is what I have at the 12 pin output socket.
Pin Schematic Actual
1 24VAC 24.8
2 24VDC 0
3 24VDC 0
4 28VDC 44
5 45VDC 44
7 -28VDC -21
8 120VAC .2
9 12VAC 4, -12
10 s 120 0
11 ? 44
12 ? -21
Looking for suggestions!

Only thing I can add for now is that I once had a 484 that I thought the voltage was out on, eventually figured out that the LED was in fact burnt out.

Doesn't appear to be your case though because your tests show you're missing the 24 v. Have you checked all the fuses?

Rather than trying to debug the circuit errors, I'm getting a replacement board. Yes, I know that is the easy way out but then again, I'm not skilled in the debug, would need outside assistance.

Only one problem doing this-- If the failure was caused by something "OFF this board", a "new" board is likely to fail instantly, on power up--- Ron Rich

OK, I understand your comment. However, if I fix the existing board, I'll face the same issue. How likely is it that something downstream can zap the rectifier board?

I dono--no experience/no crystal ball--how likely izit something failed internally ? Ron Rich