Texas 2G381A .Germanium

[Johnnyorange500]

Hi, I bought this taking a risk hoping it would work in a Tonebender mki. But the gain and leakage ended up being very high!
Any other ideas what this would work in pedal build wise? Cheers
Johnny

Texas 2G381A .Germanium Transistor.

Leakage uA = 456
hfe @ib=4uA = 187
hfe @ib=40uA = 301

 

[MobyOctopad]

Hmm, maybe as Q3 in an FZ-1?

 

[Johnnyorange500]

Hmm, maybe as Q3 in an FZ-1?

Cool! Thanks will look into it.

 

[andare]

Have you tried it in the MKI? In Q3 it might just work, that circuit is crazy.

You can also try a 1.5

 

[Johnnyorange500]

Have you tried it in the MKI? In Q3 it might just work, that circuit is crazy.

You can also try a 1.5

I might do.. I’m getting a little torn between people saying it might work or it most definitely won’t work. Won’t harm in trying tho so will give it a go when I breadboard it. will report back on the results when I get around to it.

 

[PedalBuilder]

It might work nicely in Q2 or Q3 of a Tone Bender Mk. II, too. I've tried transistors with hFE as high as 481 and leakage as high as 500µA in those slots and had great results. Just make sure to use trimmers on the collector resistors and everything should work fine. Might also be worth trying the old trick of using a germanium diode to shunt some of the excess leakage to ground if you find that it's too much for the circuit.

 

[Johnnyorange500]

It might work nicely in Q2 or Q3 of a Tone Bender Mk. II, too. I've tried transistors with hFE as high as 481 and leakage as high as 500µA in those slots and had great results. Just make sure to use trimmers on the collector resistors and everything should work fine. Might also be worth trying the old trick of using a germanium diode to shunt some of the excess leakage to ground if you find that it's too much for the circuit.

That’s great! Some great tips too. Thanks buddy.

 

[Johnnyorange500]

Sorry me again. I know I’m using the dreaded TC1 tester but does the readings match the values I wrote above? I’m having trouble determining the leakage..

 

[andare]

Sorry me again. I know I’m using the dreaded TC1 tester but does the readings match the values I wrote above? I’m having trouble determining the leakage.. View attachment 49683

Iceo is the leakage, 0.39mA aka 390uA. Quite a lot for a Tone Bender but it might just work.

Why dreaded? The TC1 is great!

 

[Johnnyorange500]

Iceo is the leakage, 0.39mA aka 390uA. Quite a lot for a Tone Bender but it might just work.

Why dreaded? The TC1 is great!

Ha! Sorry people seem to be in two minds about it. I don’t mind it..But hey, you might of saved me £80 pounds by not buying a DC atlas. Which I was thinking about. Cheers again for you wisdom Andare.

 

[andare]

Ha! Sorry people seem to be in two minds about it. I don’t mind it..But hey, you might of saved me £80 pounds by not buying a DC atlas. Which I was thinking about. Cheers again for you wisdom Andare.

No wisdom, I stole what little I know from here and other forums plus some breadboarding.
The DC Alas is still better of course but for simple needs the TC1 works in a pinch.