What to do with low gain germaniums

[Perrow]

I bought 100 germanium NPNs from ebay and ended up with ~6 FF-able transistors, and 90+ lower gain transistors. Most of them with a gain of about 30 to 50.

Fuzz Faces can't be the only cool germanium circuit, or is it? Surely there'll be other circuits that benefits from some germanium love.

[petemoore]

  Leakage and gain are the two dealios with Ge's.
   Leaky Ge's allow current through which steals from actual gain and adds to noise.
  Non-leaky Ge's with low gain...it's still gain and leakage that matter, but consideration that multiple stages will be needed to achieve X gain, getting noise to not also be multiplied [non leaky ones first ?] might be the deal.
   Perhaps something like RM>FF or 3 transistor Fuzz [Tonebender] are worth trying gain tweeks with.

[Earthscum]

Use a low leakage NPN in the Photon Buzzard... gain didn't really seem to matter. If you have one that leaks a couple ten uA, it really softens up the sound and makes the "shape" knob do more.

NPN Tonebender... ?

[Toney]

 Q1 and 2 in a Buzzaround.
Just need another high gainer and you're good to go.

[John Lyons]

Try the 50ish hfe in a fuzz face. You can go pretty low and still something nice.

[smallbearelec]

Build a Sziklai Rangemaster:

http://www.smallbearelec.com/HowTos/GeDarlingtons/GeDarlingtonPairs.htm

As others noted, the low-gain devices will also be fine as input for TB MK II or Buzzaround. could be useful as Q1, Q2 in 3-Knob TB.

[Toney]

Sziklai pair Rangemaster...nice idea 

[LucifersTrip]

I always recommend this for builders who bought a bunch of ge's for FF's, but the hfe's turned out too low. It's loud & brutal and sounds nothing like a FF.



Also, great for the darlington pair in a Buzzaround, Tonebender MK IV, etc...

[Perrow]

Sounds like me and my breadboard have something to do for a while.

Thanks everybody.

[bobster]

hey lucifer ,
would i be right in saying that your schematic is basically a fuzzface with a 5-10k volume pot instead of the usual 500k?
ive gt a home build fuzz box here with transistor sockets and i sometimes put two old mullard OC45s in it with gains of about 30 - 40 and it sounds pretty sweet although not too wild at full tilt . cleans up wonderfully
i might try this vol pot change to see what it results with
c heers
rob

[brett]

Hi
Congrats on getting 6 good devices.
Ebay is a high risk low return option for buying Euro and American Ge devices.
Low hFE devices are more-or-less useless (unless they are Russian or Jap devices that are much lower leakage and lower noise).
cheers

[darron]

i tried building the AMZ high leakage ge transistor buffer... was VERY noisy compared to a FET (: i tried a few transistors in there   - just my input if anyone was thinking of it.

[LucifersTrip]

hey lucifer ,
would i be right in saying that your schematic is basically a fuzzface with a 5-10k volume pot instead of the usual 500k?

no, you also remove the 470R, put the output directly off the collector, use lower gain transistors, almost always need a taming cap on Q1 or Q2 B-C (even though it's germanium), and usually set Q2 collector < than the FF 4.5v (~ 2-3v)

it was made to emulate the rare ge version of the Shin-Ei FY-2...and does indeed sound very similar:


you need to match the vol pot with the output cap. The FY-2 has .002/50K, but you could use .02/5K

edit: here's my last one with voltages:
http://www.luciferstrip.com/fuzz/fuzzface-fy2-mod2.jpg

[runmikeyrun]

what about just using the two legs as diodes for clipping in bazz fuss or other circuits?