Old Technics Amp SU-Z45

[vinidici]

My father gave me these old amp with one problem. R channel normal, but L channel sound very low and noisy. After some checking procedure i've found L output of STK2038 shows high negative voltage, R output did not. Because these ic replacement very rare, I decide to modif it with another STK series. Did anyone knows the pin configuration of these STK2038 ? Any schematics will helpfull.

[LAJ]

for schematics of possible substitutes. In the meantime, if you want to fool around with what you've got, I'd put a large electrolytic cap in the output of the channel you have the problem with. That would protect the speaker from the DC.

[raindog]

STK2038 datasheet and Application Note, Data Sheet, Circuit, PDF, Pinout | Datasheet Archive , not the most clear datasheet I've seen ( for one it's in Japanese ) but you can get some useful information from the schematic inside.