The 2N2/256-BSCP [was: Homebrew Drum Computer]

[Allison]

>
>Subject: Re: The 2N2/256-BSCP [was: Homebrew Drum Computer]
>   From: "Roy J. Tellason" <rtellason at verizon.net>
>   Date: Sat, 22 Dec 2007 01:00:25 -0500
>     To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On Thursday 20 December 2007 19:05, Chuck Guzis wrote:
>> > From: Dave McGuire <mcguire at neurotica.com>
>> >
>> >    I'd love to find a huge stash of a few thousand new-old-stock tunnel
>> > diodes. :-(
>>
>> You'll kindly observe that I had the good taste not to also mention
>> Shockley diodes, which, to the best of my knowledge, are really
>> unobtainium.
>
>Are those what were also referred to at one point as 4-layer diodes?  If so,  
>it's possible to simulate them with a complementary pair of transistors and 
>not all that many other parts.

Shotkey diodes are common.  Aka 1n5711.  Widely used in Rf and microwave.
They are low capacitance fast switching with low threshold.

Allison

>> American Microsemiconductor still offers a selection of tunnel (Esaki)
>> diodes, for as cheap as $9 the each. 
>>
>> http://store.americanmicrosemiconductor.com/diodes-tunnel-diodes.html
>
>Hmm.  :-)
>
>> I suspect a clue to the high prices is the "JAN" labeling on some of
>> the parts (i.e. military and aerospace application).
>
>Could be.
>
>> I have a copy of the GE tunnel diode handbook around here somewhere
>> (as well as about a dozen or so NOS diodes in my hellbox) that shows
>> all manner of logic circuits constructed with the little beasts.
>
>I'll have one here:
>
>http://www.classiccmp.org/rtellason/books/GE_TDM.pdf
>
>as soon as the upload completes (which will take a little while even with my 
>DSL connection).  It's a 100-page PDF file.
>
>There _will_ be a "tech books" page supporting the stuff there at some point,  
>when I can get it done.  I'm still in the process of plowing through several 
>thousand files of "stuff" that I've accumulated over the past few years,  
>editing some stuff,  tossing out some duplicates,  and trying to organize 
>what I'm keeping to be accessible through my local HTML tree.  Once I get 
>that mostly done I'll pull a tech books page together out of it.
>
>> I've never even breadboarded any of them, but the power requirements
>> look very modest.
>
>I picked up a couple of them once on Canal Street in NYC,  but that was a long 
>time ago.
>
>-- 
>Member of the toughest, meanest, deadliest, most unrelenting -- and
>ablest -- form of life in this section of space,  a critter that can
>be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
>-
>Information is more dangerous than cannon to a society ruled by lies. --James 
>M Dakin