Transistor with 6 legs?

[glops]

Anyone come across these?  I scored some goods at an electronic tinkerer's estate sale.  Some good stuff. Old switches and knobs and various other parts. The sad thing was when I showed up a dude was checking out with racks and racks and bags and bags of caps and transistors.  Obviously, he scored the gold.

Anyway, I found a few transistors that had six legs.  Measured them and it each one measured around 250-350 hfe.  Sounded good in a Fuzzrite I was doing but when I boxed it up I have bookoos RF interference like never before.  The circuit is the Fixx Fuzz that is a Germ Fuzzrite variation that has a boost on the front end.  I didn't get the RF on the breadboard but why now?  Sheilded the input and output wires which made the RF lessen but it's still there. Anyone have experiences with these 6 legged beast?.  The beast sounds too good to swap out...

[LucifersTrip]

Anyone come across these?  I scored some goods at an electronic tinkerer's estate sale.  Some good stuff. Old switches and knobs and various other parts. The sad thing was when I showed up a dude was checking out with racks and racks and bags and bags of caps and transistors.  Obviously, he scored the gold.

Anyway, I found a few transistors that had six legs.  Measured them and it each one measured around 250-350 hfe.  Sounded good in a Fuzzrite I was doing but when I boxed it up I have bookoos RF interference like never before.  The circuit is the Fixx Fuzz that is a Germ Fuzzrite variation that has a boost on the front end.  I didn't get the RF on the breadboard but why now?  Sheilded the input and output wires which made the RF lessen but it's still there. Anyone have experiences with these 6 legged beast?.  The beast sounds too good to swap out...

Are they dual transistors?  I used the 6 legged dual for a Fuzz Face. I got the usual bit of noise which was solved easily by the usual small cap (200pf) across BC of Q1 (or in this case the 1st half of the only Q)

[glops]

Thanks for the reply.  Yes, it's a dual transistor.  It reads 4JD12AB GE with no brand marking.  I will try the cap trick to see if that helps.  I never came across a dual tranny like this, really cool and sounds great!

[Govmnt_Lacky]

I recently dug up a 6-leg transistor. It was a 2N2640 from TI.

I believe it is a dual-JFET or something. Still trying to figure out what I can use it in  

EDIT: Upon further research, it is just a dual NPN. Gotta get some gain measurements now.. 

[LucifersTrip]

Thanks for the reply.  Yes, it's a dual transistor.  It reads 4JD12AB GE with no brand marking.  I will try the cap trick to see if that helps.  I never came across a dual tranny like this, really cool and sounds great!

you said the hfe was 250-300.  are both parts of the dual almost the same?  really close?  the one I used in that FF was hfe = 114/116, but I have many where the hfe has a larger spread (ie, one in the 100's and the other in the 200's). Though, they were probably, originally supposed to be matched?

I've built a bunch of Fuzz Rite and Fuzz Rite variants and I've always gotten better sounds with hfe's in the mid hundred and lower range.
In addition to the higher gains you're using, I wouldn't be surprised if it's harder to tame simply because they're right next to each other in the same circuit.

If I remember right, that FF I built had a bit more oscillation to tame than the normal FF's I've built with 2 separate transistors.

[glops]

They were around 200-250 ish. I auditioned several different GE's for this project and these tended to sound the best.  But I have it out of the box, so i should just put
some sockets in and try some things out.