01-12-2015, 10:12 AM
When I check a transistor I remove from circuit.Based on PNP or NPN I put pos. on base or neg on base and do the BE BC reading on ohm setting then do E to C. and CtoE should get no reading. then pos. or neg. opposite of what it should be. example NPN I put the neg on the Pbase and should get no reading to E or C. If this is wrong correction is appreciated. ( The Q3,4,5,6 (NPN 2SC497) and Q7,8, 2sa497 PNP I installed new with NTE128 for the NPNs and NTE129 for the PNPs Q7&8).
I suppose one of them could be bad or burnt out when I first repowered unit up but the symptom was the same as before I did any work on the unit. I have ordered new resistors and the small value caps for the board and will recheck all the transistors out of circuit.
I suppose one of them could be bad or burnt out when I first repowered unit up but the symptom was the same as before I did any work on the unit. I have ordered new resistors and the small value caps for the board and will recheck all the transistors out of circuit.