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Diabolical Artificer · 16th Sep 2021, 6:23 am

I test all my trannys with a DMM, wouldn't know about testing with an Avo, but I'm sure there's a Sticky thread somewhere on the forum that deals with testing trannies with both Avo and Dmm. AFAIK a shorted tranny would show low ohms between C & E as well as B maybe. A Q is shorthand for a transistor, from the way a lot of 70's Japanese amps labelled trannies; Q103, Q506 etc. Same as the old VT.

Right, you have the big OP Q's out, have you a bench power supply that can be current limited, what DC rails does it run off, +35 & -35v? With nothing connected test the PSU first on DC volts, then AC volts. What results do you get? Also do you have a scope?

Andy.

16th Sep 2021, 6:23 am	#16
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,662	Re: Carlsboro Cobra 1100 schematic sought I test all my trannys with a DMM, wouldn't know about testing with an Avo, but I'm sure there's a Sticky thread somewhere on the forum that deals with testing trannies with both Avo and Dmm. AFAIK a shorted tranny would show low ohms between C & E as well as B maybe. A Q is shorthand for a transistor, from the way a lot of 70's Japanese amps labelled trannies; Q103, Q506 etc. Same as the old VT. Right, you have the big OP Q's out, have you a bench power supply that can be current limited, what DC rails does it run off, +35 & -35v? With nothing connected test the PSU first on DC volts, then AC volts. What results do you get? Also do you have a scope? Andy. __________________ Curiosity hasn't killed this cat...so far.