Is there someone who can help me find out what the problem is with this receiver? The left channel is distorted and I can find out where is is coming from. I was going to refurbish it and thought by recapping it and replacing the transistors and a cleaning it would come out of it but after all the work it still has distortion on the left channel.
Here is what I have done.
I followed the posts by MTF and LarryL and have rebuilt the power supply with new caps and transistors. I have also rebuilt the protection board, amp board, replaced the outputs with Onsemi with new insulators and grease, cleaned all the switches and controls, recapped the phono board and the control amp board. The control amp board I replaced the 2sa726 with KSC992's and I tried to replace the 2SC1344's with KSC1845's but when I did I could not get any sound so I checked the 2SC1344's with my PEAK checker and they were good so I put them back in and the sound returned but it still has distortion in the left channel. I also removed and cleaned the speaker relay. I ordered one from Mouser but it just has not come in yet. I also ordered some new pots. I tried setting the voltages according to the updated posts but the left side will not adjust.
I tried tracing the signal with the signal tracer but I can find out were it is coming from.
I have no idea where to go from here. I just like working on this vintage stuff but I am not an expert. Sometimes I can find the problem and sometimes I can't. This one I have been working on for two full days and long nights. Any help would be greatly appreciated.
Here is what I have done.
I followed the posts by MTF and LarryL and have rebuilt the power supply with new caps and transistors. I have also rebuilt the protection board, amp board, replaced the outputs with Onsemi with new insulators and grease, cleaned all the switches and controls, recapped the phono board and the control amp board. The control amp board I replaced the 2sa726 with KSC992's and I tried to replace the 2SC1344's with KSC1845's but when I did I could not get any sound so I checked the 2SC1344's with my PEAK checker and they were good so I put them back in and the sound returned but it still has distortion in the left channel. I also removed and cleaned the speaker relay. I ordered one from Mouser but it just has not come in yet. I also ordered some new pots. I tried setting the voltages according to the updated posts but the left side will not adjust.
I tried tracing the signal with the signal tracer but I can find out were it is coming from.
I have no idea where to go from here. I just like working on this vintage stuff but I am not an expert. Sometimes I can find the problem and sometimes I can't. This one I have been working on for two full days and long nights. Any help would be greatly appreciated.
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