Hi,
I bought this amp with a blown transformer and installed the one from a Sidekick Reverb 30. As I Remember, the voltage outpot 2 x 24 volts.
The amplifier worked some time and the failed again. I figured out, the a small transistor , 2SB560F (Q9 on the pcb) was charred, i changed it with a 2SB560E (little lower max. current gain [h(fe)]), the amp worked again and failed, now I changed the transistor to a BC560, which is likely a substitute for the very hard to get 2SB560(F). I tested the amp for maximum 10 seconds it only make a very ugly hum/buzz. I found out, that the 2 big 0.5 Ohm / 5 W resistors get very hot (after just 10 sec).
Any suggestions ?
I also have a copy of the schematic here, but no scanner. I'll try to make a scan tommorow at work and post it then.
Thak you very much for your help,
Regards
Till A
I bought this amp with a blown transformer and installed the one from a Sidekick Reverb 30. As I Remember, the voltage outpot 2 x 24 volts.
The amplifier worked some time and the failed again. I figured out, the a small transistor , 2SB560F (Q9 on the pcb) was charred, i changed it with a 2SB560E (little lower max. current gain [h(fe)]), the amp worked again and failed, now I changed the transistor to a BC560, which is likely a substitute for the very hard to get 2SB560(F). I tested the amp for maximum 10 seconds it only make a very ugly hum/buzz. I found out, that the 2 big 0.5 Ohm / 5 W resistors get very hot (after just 10 sec).
Any suggestions ?
I also have a copy of the schematic here, but no scanner. I'll try to make a scan tommorow at work and post it then.
Thak you very much for your help,
Regards
Till A
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