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Identifying Transistors

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I have couple of transistors I'm trying to find a datasheets for and uses for them:

R2001 720

5105GE

and lot's more that I'm trying to find. I don't know if I should post all of them.
 
Old germaniums are in demand for builders of guitar effects pedals, especially fuzz pedals. I do a bit of that myself, but not for profit - I build them for my guitar-playing sons. Some of the Ge transistors in highest demand for pedals are 2N404, 2N508, OC75, OC81, OC44, AC127, AC128, AF127 and NKT275. The absolute cream of the crop are the OC81, OC44 and NKT275. Target gain for pedals is 50-80, although some folks prefer 100 or so.

If you have any of the above, I would be thrilled to buy some - maybe all. If you have a whole bunch, I would be happy to connect you with folks who build these pedals commerically and are always seeking large lots. Thanks.
 
I've been looking up some of the transistors that I have, and the only ones that I can find a datasheet for is this 2N3904 NPN Transistor, and a 2N3906 PNP Transistor.

Question: Can this transistor be used for anything? Or is it for one purpose only? Like could I use it to control a unipolar stepper motor?
 
I am sorry for the late response but Yes this diode can be used for a stepper motor. Its a basic diode alright but it is very useful for varied applications.It is preferably used in Audio circuits.
 
I have like a billion of these things!

Keep them well stored. They'll be worth a fortune in 20 years!

Are there any use for them at all? Possibly any low voltage applications?

Just use them like you use any silicium type transistor. Their base voltage to saturate is 0.3V instead of 0.7V. They are still used in high performance RF-circuits.

I also got some regular transistors with different model numbers. I'll sort through them and post some model numbers.

:confused: :confused: The first "regular transistors" were germanium type transistors. Working with the well known OC71 was phantastic. It was packaged in a black painted glass tube. Scratching off the black paint it was a perfect photo transistor. :D

Go ahead and try this with a nowadays "regular transistor". Please post if you were successful scratching off a TO92 package. :) and use the transistor as photo transistor.

Boncuk

P.S. If you happen to possess billions of "regular transistors" of the type 2N3055 (silicium) just cut the metal case 0.5mm below it's round shaped part. Place one million (there are billions) on a straight surface and wire them as diodes. They make a powerful solar panel, cheaper than you can find even in China. :)
 
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I like germanium transistors because they have a lower on-voltage they can work from ridiculously low voltages which is handy for single cell AA circuits.

Agreed.

Welcome back, Hero999! :)

(thought you'd never reappear being upset)
 
If they are germanium, sell them on ebay for big $$$.

Nope!

Give them to your son who will sell them on ebay 20 years later for big big $$$.

Boncuk
 
Although I agree that it is best practice to identify the leads using a multimeter,For this transistor invert the transistor and face the leads.From the square tag go clockwise to get Emitter,Base,Collector in this order.
The uses......
Well maybe you can simply use it as a switch or wire up simple circuits like multivibrators,which can be put to some uses.....
 
Thanks everyone, I have some tinkering to do know...I think I'll keep them, and give them so my son or something 200 years from now. lol.
 
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