Germanium transistors great/usable/useless?

TSReppe

Active member
Ok so I do have a little bit of knowledge about what the common HFE’s for fuzz face and tonebenders are, but don’t know so much about leakage and at what measurements a transistor is deemed useless. I bought some cheap asy37s from Poland to get started measuring and they’ve said to be good replacements for ac128. The transistors read:

1: hfe 400, leak 0,4mA
2: hfe 230, leak 0,2mA
3: hfe 200, leak 0,22mA
4: hfe 106, leak 0,066mA
5: hfe 75, leak 0,07mA
6; hfe 158, leak 0,1mA
7: hfe 200, leak 0,26mA
8: hfe 129, leak 0,1mA
9: hfe 152, leak 0,1mA
10: hfe 280, leak 0,36mA

I did the testings with this device http://tagboardeffects.blogspot.com/2012/08/germanium-transistor-tester.html

4,5 and 8 should be great for building a fuzz. 3, 6, 7 and 9 useable. 1, 2 and 10 to the bin?
 
at least none of them are dead. sort by hfe and you can try them all in different builds to find the best fits. some probably never will leave the sorting hat, but you will have options and subs if you need them.
 
Tone Benders need transistors with decent leakage for bias; some think leakage has a bigger impact on tone and character than gain.

You should build a Tone Vendor MkII with sockets and mix and match until you find a combo you like; I wouldn’t be surprised if 1, 2, and 10 make the cut!
 
Tone Benders need transistors with decent leakage for bias; some think leakage has a bigger impact on tone and character than gain.

You should build a Tone Vendor MkII with sockets and mix and match until you find a combo you like; I wouldn’t be surprised if 1, 2, and 10 make the cut!

I actually have one semi-finished. Thought I’d cut the ac125’s currently in it, install sockets and start putting these in. If nothing else than to see what happens. Doesn’t sound right as it is.
 
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