Vintage Transistor Radio Transistors

[bwanasonic]

I posted here back in 2003 asking about these cute little transistors from a Zenith Royal 13, and got no responses. I came across someone making earrings from them, and thought maybe this pic would spark some recognition:

http://www.etsy.com/listing/64405712/button-transistor-studs

The part #s are different, but I'd be interested in any info on this type of transistor (Ge Si ?, etc).

K

[edvard]

"Aw, who's a cute transistor?
That's right!
You are! You ARE!
C'mon show daddy some hFe, won't you?...
Aw, looky... you DID IT! you DID it!
Look at you, you skwumchus widdle chip of silly-con, you MUST be daddy's bay-bay!
I knew it, I just KNEW it!!"


Most likely Silicon.
I've never seen a Germanium transistor that wasn't in some sort of metal can.
Those are cute transistors though, and because they aren't the standard TO-9 stormtroopers they'd probably score some mojo points whilst sitting there looking snooky.
The ones in the picture are 2N3569, formerly a very common general-purpose transistor.
What's the part numbers on your babies?

[PRR]

> these cute little transistors

Original TI jelly-beans. When many transistors were Ge, hand-assembled in metal cans and sorted for usability, Texas Instruments built an automated assembly line to cook good Si parts and hide them in epoxy blobs. Very good parts, and TI would do a deal if you needed LOTS of them, because they'd gambled the company on this venture. (They won big-time.)

The specific 2N3569 part on one jewelry piece is a now-ordinary part much like a 2N2222 or 2N4401. (However at the time, such parts were NOT ordinary.)

Older mainframe computers and several of the pioneering studio consoles used bucket-fuls of parts like these. TI even put them down hot oil-wells, TI's original business before they took-off on this transistor kick.

> they'd probably score some mojo points whilst sitting there looking snooky.

In some eyes, maybe. I remember them as the days when transistor design STOPPED being fidgety, when you could rough-out a design on a martini napkin, have the factory produce it, and 99.5% of units WORKED with no oddness.

The 2N3569 is unlikely to work any different from 2N2222 or 2N4401, unless your circuit is hFE-fussy and its specific hFE happens to hit the happy-zone. I sure would not blowtorch a Zenith to recover these.

[Dragonfly]

I posted here back in 2003 asking about these cute little transistors from a Zenith Royal 13, and got no responses. I came across someone making earrings from them, and thought maybe this pic would spark some recognition:

http://www.etsy.com/listing/64405712/button-transistor-studs

The part #s are different, but I'd be interested in any info on this type of transistor (Ge Si ?, etc).

K

Kerry -
  They're silicon. I have some "small button" ones that are NPN, range from about 200-500hfe, and I have some "large button" ones that are NPN with hfe's under 50. The large button ones are just a "house number", the small ones are TIS97.
  AC

[bwanasonic]

The ones I have are marked 12112-F.

Thanks for all the info!

[bwanasonic]

And BTW, The Zenith pocket radio is in pretty good shape, so I am probably not going to scavenge it. Have fond memories of listening to AM radio on it at the beach in the 70's.

K

[Greenmachine]

Did anyone check out the rest of the component jewelery on that Etsy site? 

That's the most interested in accessories I've ever been in my life.  Weird and wonderful at the same time.

[edvard]

This may be somewhat obscure and I may be wrong, but it looks like that part number is a house number for inventory reasons.
In the Zenith Royal 500, '121-12' references a Sylvania 2N94 or 2N194 depending on what circuit board it has.
See here:
http://transistorhistory.50webs.com/royal500.html

Those transistors look nothing like the buttons you've got, but interesting article nonetheless.

[bwanasonic]

This may be somewhat obscure and I may be wrong, but it looks like that part number is a house number for inventory reasons.
In the Zenith Royal 500, '121-12' references a Sylvania 2N94 or 2N194 depending on what circuit board it has.
See here:
http://transistorhistory.50webs.com/royal500.html

Those transistors look nothing like the buttons you've got, but interesting article nonetheless.

Thanks very much for the research!