I have old germanium transistor from computers that were dumped in the 70's. The Hfe varies between 50 to 150. The Vbe varies between 110 and 230.
A couple of these have a short between collector and emittor, below 1 ohm. (The intention was to make an oscillator under 1 V. The reference I got from this group were sine oscillators. The circuit that I are going to try is a blocking oscillator that hopefully convert 1 to 6/7 volts to replace a 9V battery.)
Those shorts can be cleared by a high voltage pulse of short duration. Charge up a 1uF cap to 500V and apply it across the relevant terminals or between the case and the relevant terminal. You probably have tin whiskers and zapping them in this way is the most effective way of dealing with it.
I'd be surprised if you could bring Ge transistors back to life by such treatment. Sure, you'll blow the whiskers, but the transistor goes with it.
Jeroen Belleman
A microfarad at 500V is 125 mJ. That'll blow a crater in the active device.
Cheers
Phil Hobbs
Must be 0.1uF then. Or 0.01. There's bound to be someone on YT that's done it.
.... and wouldn't you know it - there is! This fellow uses 1000V, though:
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