UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Wireless World April 1969 Amplifier Kit. 2N3055 Transistors.

Diabolical Artificer · 24th Nov 2021, 8:29 am

Take some voltage reading across each tranny's base and emitter to see if they're on, Tr 3 & 4 should be at 0.6v ish, the 2N3055's at about 1.5v. Do you have a scope and sig gen? If so a probe at each trannys base and collector/emitter to see if you have a good signal is worth while too. Tr4 does most of the amplification, you should have a good signal there on its collector.

Andy.

24th Nov 2021, 8:29 am	#6
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,670	Re: Wireless 1969 Amp JLH. 2N3055 Transistors. Take some voltage reading across each tranny's base and emitter to see if they're on, Tr 3 & 4 should be at 0.6v ish, the 2N3055's at about 1.5v. Do you have a scope and sig gen? If so a probe at each trannys base and collector/emitter to see if you have a good signal is worth while too. Tr4 does most of the amplification, you should have a good signal there on its collector. Andy. __________________ Curiosity hasn't killed this cat...so far.