20 Dec
2007
20 Dec
'07
4:05 p.m.
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. 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
I suspect a clue to the high prices is the "JAN" labeling on some of
the parts (i.e. military and aerospace application).
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've never even breadboarded any of them, but the power requirements
look very modest.
OTOH, I've never seen a book detailing logic circuits with Shockley
diodes, though I imagine it's certainly possible.
Cheers,
Chuck
20 Dec
20 Dec
11:07 p.m.
From: cclist at sydex.com
To: cctalk at classiccmp.org
Date: Thu, 20 Dec 2007 16:05:27 -0800
Subject: Re: The 2N2/256-BSCP [was: Homebrew Drum Computer]
Hi
As a cheaper alternative to a tunnel diode, do a search for
a Lambda Diode. I used one of these circuits once to make an
oscillator that ran at over 100MHz.
Dwight
_________________________________________________________________
Share life as it happens with the new Windows Live.
http://www.windowslive.com/share.html?ocid=TXT_TAGHM_Wave2_sharelife_122007
From: Dave McGuire
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. 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
I suspect a clue to the high prices is the "JAN" labeling on some of
the parts (i.e. military and aerospace application).
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've never even breadboarded any of them, but the power requirements
look very modest.
OTOH, I've never seen a book detailing logic circuits with Shockley
diodes, though I imagine it's certainly possible.
Cheers,
Chuck
21 Dec
21 Dec
5:52 a.m.
On Dec 21, 2007, at 2:07 AM, dwight elvey wrote:
As a cheaper alternative to a tunnel diode, do a
search for
a Lambda Diode. I used one of these circuits once to make an
oscillator that ran at over 100MHz.
Oh my, there IS an almost-equivalent-to-a-tunnel-diode circuit!
That looks really, really neat...I will have to play with that!
-Dave
--
Dave McGuire
Port Charlotte, FL
Farewell Ophelia, 9/22/1991 - 7/25/2007
8:21 a.m.
From: mcguire at neurotica.com
Date: Fri, 21 Dec 2007 08:52:06 -0500
To: cctech at classiccmp.org
CC:
Subject: Re: The 2N2/256-BSCP [was: Homebrew Drum Computer]
On Dec 21, 2007, at 2:07 AM, dwight elvey wrote:
Hi
To better approximate a tunnel diode, you'd have
to put a resistor in parallel. I don't recommend doing
this as it only degrades the negative resistance.
Still, if one was to use a pair of these for a flop, it
might be more stable since at the higher voltages,
unlike a real TD, it completely shuts off. Without the
shunt resistors to bypass some current the circuit
might oscillate.
Dwight
_________________________________________________________________
The best games are on Xbox 360. Click here for a special offer on an Xbox 360 Console.
http://www.xbox.com/en-US/hardware/wheretobuy/
As a cheaper alternative to a tunnel diode, do a
search for
a Lambda Diode. I used one of these circuits once to make an
oscillator that ran at over 100MHz.
Oh my, there IS an almost-equivalent-to-a-tunnel-diode circuit!
That looks really, really neat...I will have to play with that!
10 p.m.
On Thursday 20 December 2007 19:05, Chuck Guzis wrote:
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.
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. 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
6211
days inactive
6212
days old
4 comments
4 participants
participants (4)
-
cclist＠sydex.com -
dkelvey＠hotmail.com -
mcguire＠neurotica.com -
rtellason＠verizon.net