On the left channel power amp pcb (AWH-073) replace D6, D7, Q8 and C11 (see Post 19 above). If that does not resolve it lift one end and verify the resistances of R18, R19, R23, R24, R28, R29, R30 and R31. These are all parts of the overload detection bridge on the power amp pcb.
I replaced VR1, VR2, C1, C2, and C11. I also lifted a leg on all of the resistors that merlynski suggested that I check. All of the resistors measured spot on.
I did notice that R18 and R19 are 1ohm resistors on the left channel board, and .5ohm on the right channel board.
I measured C11 with my meter and the capacitance measures correctly. I replaced it with a WIMA.
D6, D7, and Q8 all test ok out of circuit. Any suggestions on what to use as replacements for these 3?
D6: 1S2471
D7: 1S2471
Q8: 2SC869
I also noticed that the bias pot seems like it’s gotten hot at some point. I can see a bubble on one side where it looks like it started to melt. Could this be what is causing the protection to kick in early in the left channel?
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