A little metal project

Where did all those nice unijunction transistors of yesteryear go :-(
Mark Rand RTFM
Reply to
Mark Rand
Loading thread data ...
It's more fun when you toss in the other MEs (Manufacturing Engineering) to the mix. Each group thinks they are the only ones who matter. :(
Reply to
Michael A. Terrell
(...)
A sales guy I knew, frustrated with the noises made by electronic engineers dubbed their language "di double - E feedback".
--Winston
Reply to
Winston
Check two bins to the right of the Tunnel Diodes.
--Winston
Reply to
Winston
I've only worked directly for one Manufacturing Engineer and he was happy to let me design circuits and otherwise do as I pleased.
But yes, they can all become very defensive and territorial. Sometimes after the hardware is functional I work for the software group as a test engineer. Another can of worms opened.
jsw
Reply to
Jim Wilkins
Probably a few up in the attic.
Reply to
Bill McKee
They're still available. 48 cents at Digi-Key
formatting link
In the UK, Farnell's has 'em:
formatting link
Reply to
Don Foreman
Whereas, a sales guy or politician can speak for 20 minutes without saying a damned thing so it doesn't matter whether or not their utterance is comprehensible.
Reply to
Don Foreman
The surplus store near me has some but they want more like 12 bux for them. Arrgghh, highway robbery! I found a little 2.4VA 8VRMS 60-Hz xfmr in my goodiebox that should work nicely.
Reply to
Don Foreman
I found a little 2.4VA 8VRMS 60-Hz
I used to use a lot of the LT "simple switcher" eval boards. Cheap (at the time they were 8 bucks), small (1" X 2") and easy to mod.
Kevin Gallimore
Reply to
axolotl
And they are cheap. But the 2N6027/8 are PUTs, a kind of SCR-like 4-layer thyristor device, not real unijunctions (eg. 2N2646).
But Newark still has the 2N2646 :
formatting link
?in_merch=true&MER=ALT_N_L5_SemiconductorsDiscretes_None I miss LASCRs (light activated SCRs), SBS (Silicon bilateral switches), tunnel diodes, germanium transistors, clean air, tuna, Taiwan.
Best regards, Spehro Pefhany
Reply to
Spehro Pefhany
[ ... ]
How many here have ever heard of a "binistor"? A 4-pin bistable device which apparently never took off in the market. It was a four-layer device (like a SCR -- except that it had another pin to allow turning it off.
IIRC, Transitron gave it the designation 3N21. I could look it up in the old Transitron data book -- but I don't know where that is at the moment. :-)
Enjoy, DoN.
Reply to
DoN. Nichols
Hey DoN,
Reply to
Brian Lawson
I knew them as SCSs (silicon controlled switch).
Kevin Gallimore
Reply to
axolotl
Sounds like a GTO:
formatting link
--Winston
Reply to
Winston
On Sun, 10 Jan 2010 10:42:24 -0500, the infamous Spehro Pefhany scrawled the following:
Are LASCRs still available? They'd be great for a "Hey, the mailman's here! alarm. We have a local lady who checks everyone's mailbox at times, too. They'd catch her in the act.
formatting link
I guess they're good for flash slaves, too.
--============================================-- Growing old is mandatory; growing up is optional. ---
formatting link
ToolyRoo(tm) and Possum(tm) Handy Pouches NOW AVAILABLE!
Reply to
Larry Jaques
O.K. Germanium means that I have given the wrong part number. It was a silicon device. I wonder what those 3N devices were, how they earned the leading 3 instead of 2. Transitron used it as a count of junctions (e.g. one less than the number of leads.
Thanks, DoN.
Reply to
DoN. Nichols
Made by Pontiac?
Reply to
Don Foreman
First one, no. Second one, yes.
--Winston
Reply to
Winston
The xNyy pattern is from a JAN standard, if I recall. I think that the x is one less than the number of terminals, the then assumption being that one must have at least two terminals. I don't think that the number of junctions was considered, the intent being to treat the device as a black box.
I would have guessed that 3N21 was an optocoupler, or a SCR with all four layers connected. However, it seems to be an obsolete transistor type made by Sylvania and Western Electric: . However, it turns out to be a Germanium switching transistor: .
Joe Gwinn
Reply to
Joseph Gwinn

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.