Repairing Peavey PV-8.5c - Transistor substitute

[lawbadman]

Hello,

In trying to repair a PV-8.5c amplifier I have found that the current limiter transistors are blown and I cant find exact replacements.
For Q102 can a 2N2222A work suitably?
Also for Q103 can a 2SB561 work suitably?

Looking at the data sheets the substitutes seem to be fine but I need some confirmation.


Schematic is here: PEAVEY PV-8.5C SCH Service Manual free download, schematics, eeprom, repair info for electronics



Thanks,

Lawrence

 

[JonSnell Electronic]

The MPS6531 is

• Collector-Emitter Volt (Vceo): 40V
• Collector-Base Volt (Vcbo): 60V
• Collector Current (Ic): 1.0A
• hfe: 90-270 @ 100mA
• Power Dissipation (Ptot): 625mW
• Current-Gain-Bandwidth (total): -
• Type: NPN
• MPS6533 is PNP

So almost anything will do. BD137/9 etc

The amp must have suffered a catastrophic failure as they have no current path feeding them!
The only path is through a pair of 1N4148 diodes or 3k9 resistors which will certainly have blown in this case.