Which are the most desirable Ge Transistors for DIY community?

[koky]

Recently I had a lead to a seller on the flea market in my home town and it was said to me that he have a big amount of Ge tranies. The question is which numbers (I mean 2n404 , GT309 , GT307 etc.) to look for that can be used for our hobby? I know that I have to look and measure hFE but it will be stupid to go there with DMM and try hundreds of tranies.

Post numbers and I`ll check what he have at sunday.

Kostadin

[midwayfair]

Being "most desirable ones" has very little to do with whether the transistors will be "the most useful ones." What I'd do is look up the datasheets for the part numbers that the guy has. Meaning, take a smart phone with you if you have one and look them up on the spot. Look up the polarity and the gain range. Otherwise, just test a couple transistors out of each bag if you have a DMM that does that; if the gain is really low, like under 40, there are very few guitar pedals that will even work with them.

Your best bet for figuring out what the mot valuable part number is is to look at the schematics for a bunch of old fuzz pedals and then write down the part number. Not the series (like "OC"), but the specific part number. Then look up the equivalent transistor from other companies. New Market, for instance, is a brand name, but the same transistor construction as in the 213 and 275, which are very valuable, have different part numbers by RCA or Telefunken, for instance.

Here are the most useful "numbers":

PNP 40-80: Q1 in classic Fuzz Face
PNP 80-130: Q2 in classic Fuzz Face and Q3 in a MKII, Three-knob bender, or Buzzaround
NPN 40-50: Q1 in a low-gain NPN fuzz face
NPN 60-70: Q2 in a low-gain NPN fuzz face
PNP 40-60: Q1 in a Percollator
PNP 20-40: Q1 and Q2 in Tonebender MKII, but requires moderate leakage
PNP 70-80: classic Rangemaster, requires low leakage; Skreddy Screwdriver if moderate or high leakage

Also, a bunch of my projects are made to work with lower gain NPN Ge transistors 50-70hfe. I'd buy a handful of any NPN black glass transistors you see near that gain range, like 7113, or RCA metal can stuff like the 2N1304.

[selfdestroyer]

That is some great information Jon.

[koky]

For some reason this guy didn`t show up today so I`ll check again next week.

Kostadin

[Gledison]

It's funny that the Germanium Wizzard Chromesphere didn't show up yet after the two letters "Ge" appeared here!!
Thanks Jon for the information. just saved it!!
Cheers

[twin1965]

Been playing around with low hfe pnp's (GT108V) in a fuzz face/sunface type circuit with blend cap mod and bias control and it sounds fantastic. Its on the  breadboard but I think this will turn into a fully fledged pedal! hfe is 50-60 on q1 and 60-70 on q2. Very low leakage. Don't underestimate low hfe germs!

Sent from my GT-I9100 using Tapatalk 2

[Gledison]

Been playing around with low hfe pnp's (GT108V) in a fuzz face/sunface type circuit with blend cap mod and bias control and it sounds fantastic. Its on the  breadboard but I think this will turn into a fully fledged pedal! hfe is 50-60 on q1 and 60-70 on q2. Very low leakage. Don't underestimate low hfe germs!

Hey mate.
I also got some of the GT108V and indeed very low leakage. the ones I've got also have very low hfe. will breadboard as well and see if I can use only them for Q1 and Q2...
cheers

[davent]

Another low gain breadboard player here, if you haven't already check out this great article on Small Bear about using the low gain Ge's as a Darlington pair or Sziklai pair, they do sound very good.

https://www.smallbearelec.com/HowTos/BreadboardGeDarlingtons/BreadboardGeDarlingtons.htm

dave