Recent Experience with Chinese and Soviet Germanium Transistors (Measurements Included!)

[shoujonoise]

Very cool! Thank you for reporting on your experiences and observations.
Could you share the seller you ordered the Chinese transistors from? I am interested in ordering some of those 3BX31B to see what is up.

 

[PedalBuilder]

Very cool! Thank you for reporting on your experiences and observations.
Could you share the seller you ordered the Chinese transistors from? I am interested in ordering some of those 3BX31B to see what is up.

I ordered the 3AX31C and 3BX31B from UM2part Store, but be forewarned that the 3BX31Bs that I received from them were largely useless:

Update on the 3BX31B NPN transistors: they were almost all duds. Out of the 100 transistors, all but 8 were dead or had an hFE <8. AliExpress was quick to issue a refund, but I did end up with 8 more or less useable NPN germanium transistors:

hFE	Leakage
97​	201​
82​	112​
66​	85​
66​	101​
64​	160​
58​	299​
53​	217​
46​	41​

The ones that did work do sound good, and the highest gain one features prominently in my Spaceman Gemini IV clone, which is rapidly becoming one of my favorite pedals (even if the board that I used was an absolute nightmare to fit into an enclosure). If you can find any, the 3BX31C have slightly better specs than the A and B varieties, but I haven't ordered any yet to see for myself.