Germanium transistors

[marcrochotte]

I tore apart an organ to dispose of it, and ripped out a lot of circuits with what i think are germanium transistors..there are a lott of them, like about sixty maybe. some of the the labels on them are:
4jx1d630-9 526
4jx1d610-2 508
4jx1d610-2 521
4jx1d610-2 513
4jx1d610-2 526
4jx1d630-9 504

if those numbers mean anything to anyone, that would be helpful. i really honestly know nothing about transistors, but have made a few distortion pedals and keep reading about using germanium transistors. could i use any of these in a fuzz pedal circuit?

thanks!
-Marc

[marcrochotte]

(they are made by G E)

[JHow]

If they are american, might they not be 2N series, like 2N526, etc.? Did you say what the case is TO-1, TO-5 etc?

As to fuzz face, the answer is probably 'yes, but you'll want to test them'.

Here is some could info from frequent poster RG:

Technology of the Fuzz Face - Frame Definition

[Enzo]

We don't care who made the transistors, but if we knew who made the organ, we could get a clue about the parts.

I would doubt the 2N theory, those look like OEM part numbers. Lowery or Wurlitzer or whoever had the parts stamped with their part numbers instead of the transistor type. In fact the 526 and such at the end of each one looks more like a date code. 26th week of 1965, 8th week of 1965, etc. The long part is the part number.

[imaradiostar]

If you want to know if they're germanium just put your volt meter in diode test mode and look at the voltage drop across the junctions- silicon will be about .6 volts, germanium about half that. If they are germanium I highly recommend using RG's germanium transistor leakage tester to see how much they leak and what their "real world" gain is.

Not bragging or nuttin' but I found a bunch of old NPN JAN germanium transistors at work- only one of the 7 I've tested was too leaky to use in a fuzz face and all the gains fall between 80 and 150. Yes, they're NPN- the place I work at absorbed an old Navy lab that needed the NPN components in the earliest days of solid state construction so I lucked out.

jamie

[marcrochotte]

it was a conn organ, heres some pics, sorry the quality sucks, i cant find my camera ha had to use the phone..

[JHow]

Don't know if this helps, but found this link:

CONN Parts Catalog

Didn't see your numbers in there, however.


Also found this old ebay one, whith the 4jX1D610 part number....

http://cgi.ebay.com/GERMANIUM-TRANSI...QQcmdZViewItem

[marcrochotte]

i tried making a basic fuzz face circuit with it, and all i get is a short farty output. it sounds fuzzy, but really short, even if i play full chords or have settings high. could this be something i could fix with just a resistor change? cus it definitely makes sound, and i checked the transistors

[JHow]

By "short", do you mean the notes decay rapidly and don't sound as long? It sounds like it could be some bias issue. I'm not a guru, but maybe if you have a look at the voltages on each pin and post those one of the gurus can weigh in. If this is a perf board circuit, you might have missed a ground connection or something.

[Ronsonic]

i tried making a basic fuzz face circuit with it, and all i get is a short farty output. it sounds fuzzy, but really short, even if i play full chords or have settings high. could this be something i could fix with just a resistor change? cus it definitely makes sound, and i checked the transistors

Strongly suspect that it is misbiased. That sounds like the sort of gating behavior you'll get. Find the paper out there on the "Science of the Fuzz Face" or whatever it's called and it will explain how to get you dialed in. Or at least where to put the trim pots.

[R.G.]

Strongly suspect that it is misbiased. That sounds like the sort of gating behavior you'll get. Find the paper out there on the "Science of the Fuzz Face" or whatever it's called and it will explain how to get you dialed in. Or at least where to put the trim pots.

"Technology of the Fuzz Face": it's part of the Technology of... series for effects at geofex.com.

Try as I might, I can't get enough people to go read geofex first. It makes so many forum questions unnecessary.

[Mark Hammer]

Odd, isn't it, that the internet at once encourages so many to treat what they see as gospel truth, without reservation or questions, yet balks at treating a single site as dependable. Just one of life's little paradoxes.

[JHow]

...Try as I might, I can't get enough people to go read geofex first...

geofex cannot be absorbed in just one reading. One often has to read the articles several times (if one is me) for the concepts to sink in.

And the site is completely lacking in pictures of scantily-clad women (which research has shown to be a key driver of web site traffic!).

[R.G.]

Odd, isn't it, that the internet at once encourages so many to treat what they see as gospel truth, without reservation or questions, yet balks at treating a single site as dependable. Just one of life's little paradoxes.

Butbutbut... this is all stuff *I* said, so it must be perfect!

And the site is completely lacking in pictures of scantily-clad women (which research has shown to be a key driver of web site traffic!).

I should have known that there was something fundamental I was not doing right.

[Mark Hammer]

Well, Jack Orman had a link to "Live Nude Shakespeare" (a real, though somewhat questionable, entity) at his AMZ site for the longest time. Maybe you need a link "Dostoyevsky in the Raw" or "Rumi...topless".

Actually, without meaning to be too critical, the left side of your home page IS a little on the tiny side, font-wise, and easily overlooked by those those distracted by the flashier content in the "New at GEO" listing. No need for bells and whistles or Flash animation. Just some bigger letters in Arial for that stuff in the left-hand column.