I have this amp under work and the +/- 45V fuses have blown. I also found a schematic for a AU7900 amp, which seems to be almost the same, however the scan is so poor that I cannot make out the values of resistors R72 and R71 on the main amp PCB.
So if you have a schematic, or if you know the values for these resistors, let me know.
-J-
Joe,
I can't really answer your question as I don't have a diagram for that model. However, I've noticed that the fusible (flameproof) resistors on many of these Sansui receivers seem to go WAY off value. I initially noticed it with the 150 ohm ones, and these usually seem to be the worst. I'd suggest checking the value of all of them on the amp board. These resistors usually have a grayish matte finish to them, and are usually stood up off the board. They can be 1/4 watt or higher.
Regards, Tim Schwartz Bristol Electronics
a
R71 and R72 are 4.7 ohm, 1 watt resistors. If these are open you have some serious oscillation problem in the power amp or C33, C34 are defective as well.
Good luck.
-- David Farber David Farber's Service Center L.A., CA
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