Frank Wissman

Hi, John, I agree, purple is -39V, thank you. And thank you for the detailed, patient walk-through. I don't have any voltages to measure, all caps were removed and I've made a board to replace them with fresh caps. I think what threw me is the different wire size, +39 is about 20AWG and -39 is almost 16AWG. Cheers, Frank

Oh boy - I'm starting to think these are ground leads from the driver stage back to the tab in the chassis by the original caps. Anyone know for sure?

Hi, John, Yes, I agree - I have the SM (service manual), and I expected the purple wires to be +/- 39V, but they do not directly connect to any of the 2N3055 collectors or the emitters through either the 27 or 33 ohm resistors. I mentioned only the +39V in my initial thread, trying to simplify things. In the SM, section 1.C.3, +39 Volt Lead Dress - this update refers to a red wire from C50. In this amp and in pictures of others, the purple wires appear to be factory installed and I no longer believe these to be +/-39V. Hi, Anyone who has worked on these - the purple wires go where? Thanks, Frank

Hi, Gang, I am trying to repair an AR amp that someone else started, the PS has been taken out already. I have the SM and update notices. I expected the 2 ~16 ga purple wires to be +/- 39V to the drivers & outputs. But when I visually trace the wires, and ohm them out, neither go to the collectors of Q19, Q20, Q23, & Q24. Nothing else looks likely. This should be trivial and I'm stumped - what are the 2 purple leads, please? Thanks, Frank