Because of it's age, I replaced 5 of the largest standing capacitors because they were electrolytic and they say after 10-15 years you should. I also found a Motorola IC chip that had broken in half and a fired 10 ohm resistor. But even after replacing these the amp will not work right. While I am a novice I have learned a few things. I've gone across the board and checked most of the IC's (leg 8 but a few that were different according to the schematic) and they read 15.5vdc consistently. So how do you narrow down the problem area? I thought that would do it but it revealed nothing that I understand. The amp just makes an awful noise when turned up and has heavy distortion and will not get loud like it should. I did unplug the pre-amp side from the power board and the modulation sound was very quiet (very low hiss). I'm looking for suggestions at this point and attached the schematic. Thanks in advance.
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