Paul,
Just to pick your brains, while we are talking about Germanium Diodes,I recently had a problem with a Stereo Amplifier(old NZ-made), that had Germanium Transistors in the Final Power Output section,(AC188, AC187), would it be possible to replace these with say a, BD139 or BD682,as they have similar bias currents and voltages.
The original devices were damaged when the speaker wires were shorted.
This type of amp has adjustment for the Collector current,although the Emitter resistors are blackened(excessive current?)
These resistors are wire-wound, almost like an inductor, and are air-cored,made of ceramic coated copper wire.
Helllllllppppp!!!!.