edit: NVM. I forgot to put in the Zener diode. How do I delete this post...
Hi All,
I've been working on rebuilding one channel of a Tandberg TR 2080 Power Amp. When I received it there were numerous failed transistors, melted resistors, some damaged traces.
I've replaced all the transistors except Q901/903 (which I did pull and test). Replaced all diodes. Replaced all electrolytic caps. Pulled a leg up and tested the value of every resistor. Replaced all bad resistors, plus the output emitter resistors.
Powered it up with a dim bulb tester and it seemed okay. Powered it straight from my variac and started getting set up for the quiescient current calibration. After about two minutes R935 melted.
I could use some help sussing this out.
Schematic attached
Hi All,
I've been working on rebuilding one channel of a Tandberg TR 2080 Power Amp. When I received it there were numerous failed transistors, melted resistors, some damaged traces.
I've replaced all the transistors except Q901/903 (which I did pull and test). Replaced all diodes. Replaced all electrolytic caps. Pulled a leg up and tested the value of every resistor. Replaced all bad resistors, plus the output emitter resistors.
Powered it up with a dim bulb tester and it seemed okay. Powered it straight from my variac and started getting set up for the quiescient current calibration. After about two minutes R935 melted.
I could use some help sussing this out.
Schematic attached
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