With ZD1 we did measure all the pins and they were all ok. Amp actually plays very nice even without LM358 but you can hear loud pop on power switching on.
Do you know where can I contact Steven Mantz? Some mail address or similar... it's tough chance he still got a hold on those old diagrams for this lower end line. As far as I know these were built around 94/95 , same time as generation X.
There is brown fixative as you mentioned, on few places. But we haven't checked if it did any damage. Sorry I didn't posted my guts pics, but will do it in next few days.
Do you know where can I contact Steven Mantz? Some mail address or similar... it's tough chance he still got a hold on those old diagrams for this lower end line. As far as I know these were built around 94/95 , same time as generation X.
There is brown fixative as you mentioned, on few places. But we haven't checked if it did any damage. Sorry I didn't posted my guts pics, but will do it in next few days.
I have contacted Mr Mantz about this matter and this is what his answer was:
"LM358 is for protection and you must trace backwards from pin 3 and pin 5 of where the high going signal comes from."
Now I have attached new pics of my amp so you can see better what's going on inside. My father did detailed measurements and here are the results:
IC1 - TL594 , IC2 - LM358 , IC3 - LM833 , IC4 + IC5 - TLO74 , IC3,4,5 have a +-15v supply constantly , ZD1 - 5,5v while ZD2 -31,5v. I still cannot find why pin 8 on LM358 has no supply directly from remote. ZD1 takes +12,5v from remote on cathode but anode is on 7v.
"LM358 is for protection and you must trace backwards from pin 3 and pin 5 of where the high going signal comes from."
Now I have attached new pics of my amp so you can see better what's going on inside. My father did detailed measurements and here are the results:
IC1 - TL594 , IC2 - LM358 , IC3 - LM833 , IC4 + IC5 - TLO74 , IC3,4,5 have a +-15v supply constantly , ZD1 - 5,5v while ZD2 -31,5v. I still cannot find why pin 8 on LM358 has no supply directly from remote. ZD1 takes +12,5v from remote on cathode but anode is on 7v.
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