A little metal project

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. :(

(...)

A sales guy I knew, frustrated with the noises made by electronic engineers dubbed their language "di double - E feedback".

--Winston

Check two bins to the right of the Tunnel Diodes.

--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

Probably a few up in the attic.

They're still available. 48 cents at Digi-Key

In the UK, Farnell's has 'em:

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.

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.

On 1/9/2010 11:27 PM, Don Foreman wrote: 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

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 :

?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

[ ... ]

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.

Hey DoN,

I knew them as SCSs (silicon controlled switch).

Kevin Gallimore

Sounds like a GTO:

--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.

I guess they're good for flash slaves, too.

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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.

Made by Pontiac?

First one, no. Second one, yes.

--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