Anyone have a schematic for the amp i an REL T-3 subwoofer?
My T-3 is blowing fuses. I'm pretty sure the output transistors are shorted. The appear that way when measure in the circuit. I'll pull them today and retest.
In tracing the circuit, it does not appear that there is any voltage regulation for the output transistors. Current flows from the transformer to the PS caps and then to the transistors.
I can't find any VR ICs on the board, though there is one op-amp that could be in a part of a VR circuit.
Is it comment for outputs to be driven from an unregulated source?
Finally, assuming the transistors are bad and a replace all 4 (2 NPN, 2 PNP), are there any guidelines for setting the idle current if I don't have a schematic or manual? Should I just leave it as is in that case?
thanks,
James
My T-3 is blowing fuses. I'm pretty sure the output transistors are shorted. The appear that way when measure in the circuit. I'll pull them today and retest.
In tracing the circuit, it does not appear that there is any voltage regulation for the output transistors. Current flows from the transformer to the PS caps and then to the transistors.
I can't find any VR ICs on the board, though there is one op-amp that could be in a part of a VR circuit.
Is it comment for outputs to be driven from an unregulated source?
Finally, assuming the transistors are bad and a replace all 4 (2 NPN, 2 PNP), are there any guidelines for setting the idle current if I don't have a schematic or manual? Should I just leave it as is in that case?
thanks,
James
Tested the output transistors and one of the PNPs is shorted.
I think I can just replace the pair of PNPs . If my understanding is correct, while the other PNP in the pair would have been stressed, the pair of NPNs shouldn't have noticed a difference since they are only active when the PNPs aren't and thus the shorted PNP should have had no affect on the NPNs.
Is there a way to purhcase a matched set?
They are B817C.
Thanks
I think I can just replace the pair of PNPs . If my understanding is correct, while the other PNP in the pair would have been stressed, the pair of NPNs shouldn't have noticed a difference since they are only active when the PNPs aren't and thus the shorted PNP should have had no affect on the NPNs.
Is there a way to purhcase a matched set?
They are B817C.
Thanks