Hi! I need some help finding out whats wrong with a Denon PMA-925R amp. Right after a relay clicks in, it makes burning smell and maybe after 5-10 seconds, there was a smoke. Any ideas on what can be causing this? One channel seemed to work fine. While the other one didnt produce any sound and burnt the resistors. Resistors still show good readings, so I can use them for further testing.
Dim bulb tester - Lights up, and dims off just a little bit (maybe 5-10% dimmer than at start). But I think not enough to indicate that everything is fine. Relay clicks after much longer, but didnt make any smell. So maybe there is an overvoltage somewhere?
The whole service manual can be found here - https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiSxa-i95HuAhVJAhAIHXksCUIQFjAAegQIAxAC&url=https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Denon-PMA-725R-Service-Manual.pdf&usg=AOvVaw129kKbViTvvUVBAIntyHfE
---Update---
The upper transistor is shorted at pin 2 and 3. The transistor below is reading 130ohms at pin 2 and 3.
Dim bulb tester - Lights up, and dims off just a little bit (maybe 5-10% dimmer than at start). But I think not enough to indicate that everything is fine. Relay clicks after much longer, but didnt make any smell. So maybe there is an overvoltage somewhere?
The whole service manual can be found here - https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiSxa-i95HuAhVJAhAIHXksCUIQFjAAegQIAxAC&url=https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Denon-PMA-725R-Service-Manual.pdf&usg=AOvVaw129kKbViTvvUVBAIntyHfE
---Update---
The upper transistor is shorted at pin 2 and 3. The transistor below is reading 130ohms at pin 2 and 3.
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