Germanium transistors besides AC128?

[Branimir]

I think i have some old Ge transistors in my basement, sorted in some box, and I think some of them could be used for fuzz face...

Besides AC128, anyone had success with other types of germanium transistors... AC188?

Any others?

Thanks!

[Cliff Schecht]

I think i have some old Ge transistors in my basement, sorted in some box, and I think some of them could be used for fuzz face...

Besides AC128, anyone had success with other types of germanium transistors... AC188?

Any others?

Thanks!

I have a few PNP germaiums that just say GE-2 with some specs and some that say GT-5 which are the PNP versions. Anybody know if I can use these? Here's the specs on the packaging.

I don't know too much about fuzz faces, so I have no idea what trannies to use for FF besides the AC128.

[Steben]

I think i have some old Ge transistors in my basement, sorted in some box, and I think some of them could be used for fuzz face...

Besides AC128, anyone had success with other types of germanium transistors... AC188?

Any others?

Thanks!

These can be used for FF:
PNP AC122, AC125, AC126 (all usually less noise than AC128 in fact) and also AC188, yes and NKT275
NPN AC127; AC187

[Thomas P.]

and the AC151(R)

[JHS]

AF127 sounds fine too.

All those Ge-trannies stry a lot and it's hard to find 2 AC128 ina a bunch that produce the same sound in a circuit, IMHO low noise and leakage are more imortant than the trannie type.

JHS

[Gila_Crisis]

i wnna build a fuzz which use ac128 but i got some ac187 (if i remenber well), can i use those as well?

[Meanderthal]

I have a few PNP germaiums that just say GE-2 with some specs and some that say GT-5 which are the PNP versions. Anybody know if I can use these?

I have some of those GT-5 trannys, they work fine in a FF. Nothing beats the pair of TI that I got from smallbear though!

[Gila_Crisis]

i wnna build a fuzz which use ac128 but i got some ac187 (if i remenber well), can i use those as well?

i checked they are TFK AC188k 30

[Dragonfly]

AC188, AC125, OC81, OC76, OC44, 2N404A, etc, etc.  can be ALL good/great for FF's.

for NPN, I really like AC187's and OC140's.

AC

[Gila_Crisis]

with AC188 what hFE do you suggest? hi or low values?

[zyxwyvu]

There's a lot of good information on which Ge transistors are useful here:

http://www.smallbearelec.com/HowTos/FuzzFaceFAQ/FFFAQ.htm

[Steben]

with AC188 what hFE do you suggest? hi or low values?

I would be jelly pie if I would say the gains should be different than with AC128.

SO: 80-120 for example, or 100-100. A lot of discussions about this. Just remember that "Germanium" says more than a specific number. The chance two AC188's differ more in sound than a 188 and a 128 is very big.

[Branimir]

There's a lot of good information on which Ge transistors are useful here:

http://www.smallbearelec.com/HowTos/FuzzFaceFAQ/FFFAQ.htm

Great! Thanks for the link!! I hope I'll dig up something useful in a pile of trannies in my basement!

[mac]

My personal taste are the matsushita's 2sa101/2/3/4 family pnp ge and 2n388 npn ge from texas inst.
Also matsushita 2sb172/175/176, toshiba 2sb54/56, 2sa49/52/53 and hitachi 2sb77.

The ACxxx in my country are all from unknown brands and usually toooooooo leeeeeaaaaaky.


mac

[Ronsonic]

I'm getting great sound from 2N1304 and 2n1305.

Ron

[mac]

... and 2n1114 npn... My npn version has a (2n388; 2n1114) with (hfe=73, leak=29ua; hfe=123, leak=120uA)

Well, in fact any Ge with a transition freq ft far above 20khz, leaking less than 200uA and with gain around 50 - 150 will sound good. I mention the ft because I have a bunch of 2sd352 with <hfe>=65 at Ibase=4uA, <leak>=200uA, but ft=10khz that sound a little dark for a FF. But in the case of the TB MKII & 3-knob that make a lot of higher freqs the low ft is fine. It depends on your amp too, and your ears.


mac

[jmusser]

Marty Mart and I made several circuits using various Russian transistors like the GT308V,GT308A, GT308B, GT309B, & GT309A, among others. They make great Tone Benders. The main thing with these guys, is the pinouts are non standard. Several months ago, you could get hold for something like $12.00 for 50 off Ebay. They're very consistant. If you get hold of some, I can give you the information on the pinouts.

[Big Red]

does anybody know if 2N128 would be suitable?

[Branimir]

Well the Ge fishing in my basement was successful! I found AC 122/30 transistors, I measured their Hfe's, and got values between 58 (lowest) and 96 (highest), and I have total of 8 transistors.

These devices aren't new, they're been taken out of some apparatus at least 20 years ago, so I have no clue how they're gonna work in FF...

Quick! PCB's to the etching pond!

[Cliff Schecht]

I just threw together a fuzz face using some random transistors I found on an old board that I got from a neighbor who worked at IBM. From the looks of it, the board is from the 70's and really, I was just trying this out for the sake of doing something. I pulled out some trannies and found out they were PNP (They have really ambiguous markings, like one says "6302" and "2585" and is a TI part, but it has no real part information. Anyways, I threw together the circuit and was getting a strange gating type sound that sounded like misbiased trannies, but it was also getting a strange tremolo type effect. I threw in some silicone pnp's just to be sure everything was working and it had just about the same effect. I'm not too familiar with the FF and all of its varients, aside from what I've read, but I'm hopefully going to have something built so I can play around with the circuit a bit, especially since a new space just opened up on my pedalboard.

Sidenote/question: The forward voltage drop on a silicon diode is about .7, whereas on a germanium it's around .2. Can the same assumption be made for Ge and Sil trannies? I was basically assuming that if a transistor is Ge, the fvd between the emitter-base and the collecter-base would be around .2.