Germanium transistors from old radio?

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Germanium transistors from old radio?

Postby ozbird » 19 Sep 2011, 12:37

Hi all,

I've been doing some cleaning up at home, and rediscovered my grandmother's old AM radio - an AWA Radiola (Model B29 = Radiola Eight, I think; 1955-1960s based on the ARTS&P license sticker.)

What caught my eye was the "transistor complement" label inside the back flap, listing eight germanium transistors and one germanium diode. :-)
The listed types are: AWV 2N374/2N1636, AWV 2N373/2N1634 (x2), AWV 2N406 (x2), AWV 2N408 and AWV 2N217S (x2); the diode is an Anodeon 1N295.
I can see that one of the 2N373/2N1634 transistors is actually a 2N1638, so there may be some substitutions.

Assuming they are still in working condition, are any of these suitable for Fuzz Face etc. stomp boxes?

Cheers!
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Re: Germanium transistors from old radio?

Postby joeboo88 » 19 Sep 2011, 13:08

hi Ozbird, nice find! You should look up the trannies on google and see if they are PNP or NPN that would be a good start. As for specific (yeah thats a great one) or not i dont know.
You should then get their value - hfe- from a meater.
I came across 2 boxes of junk, and alas they only yielded 2 GE's, and another i had- totally different trannies but i used them for a 3 knob tonebender which is my favorite pedal. I read that 1 trannie in that cct only does the fuzzing, so good luck, someone else here will know more :mrgreen:
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Re: Germanium transistors from old radio?

Postby ozbird » 19 Sep 2011, 14:03

Hi joeboo88,

joeboo88 wrote:hi Ozbird, nice find! You should look up the trannies on google and see if they are PNP or NPN that would be a good start.


I'm pretty sure they're all PNP - not unsurprising with Ge types.

I found this site which describes some of the (1957) transistor functions:
http://sites.google.com/site/transistorhistory/australian-semiconductor-manufacturers/history-of-awv

I'm guessing that the 2N406 is most suitable (Small Signal AF), but the 2N408 and 2N217 (Large Signal AF) might be okay too. (I'm not sure what the "S" suffix
on the 2N217S indicates.)

joeboo88 wrote:I came across 2 boxes of junk, and alas they only yielded 2 GE's, and another i had- totally different trannies but i used them for a 3 knob tonebender which is my favorite pedal. I read that 1 trannie in that cct only does the fuzzing, so good luck, someone else here will know more :mrgreen:


Thanks for your advice.

The one thing that holds me back from whipping out the soldering iron is that still works... I have no idea if it has any value to a radio collector. :hmmm:
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Re: Germanium transistors from old radio?

Postby ozbird » 27 Feb 2013, 17:22

A follow up to my old post.

After much dithering, I decided to bite the bullet and salvage the transistors from the radio.

Here's what was actually fitted:
Diode:
[*]1 x OA90[/*]
Transistors:
[*]1 x AS2 (wired as a diode!)[/*]
[*]2 x 2N406, one with red printing[/*]
[*]2 x 2N217S[/*]
[*]1 x 2N408[/*]
[*]1 x 2N1638[/*]
[*]1 x 2N1639[/*]

Untwisting the legs of the AS2 was a challenge (and unnecessary if my quick leakage test was accurate.)

I'm still hopeful of being able to reuse something, but pre-screened components are a lot less effort!
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Re: Germanium transistors from old radio?

Postby ozbird » 27 Feb 2013, 23:21

Make that 2 x 2N1638
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