Golden oldies

Apr 03, 2012 6 Replies

The 2N2646 UJTs came today. Could not resist to try some things,



A 30 second LED flasher


+9V ------------------------------------ | | | | | --- [ ] [ ] \ / -> green LED | 50k | 2k2 --- | to | | | 100k |--------- | e |--- b2 |-------\| 2N2646 | |--- b1 === | --- [ ] 10 | 470u | /// ///

What's the efficiency of that? I'd guess it's in the 0.01% ballpark.

PUTs, the synthetic version of the UJT, were interesting parts.

John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators

Were? They're as cheap as any other four layer device today.

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No SMTs and no product development, but there's still fractional millions in stock / being made.

PUTs have lower "leakage" than UJTs (which don't so much "leak" as be a resistor in the off state) so the efficiency will be higher, too.

Tim

-- Deep Friar: a very philosophical monk. Website:

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John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators

Doesn't help if you can't get it:

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Non stocked, Digikey doesn't even have a database entry for it.

Oh well, probably only China buys 'em anyway for legacy products, and they're quite happy with THT.

Tim

-- Deep Friar: a very philosophical monk. Website:

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Digikey hardly stocks anything any more.

--

John Larkin Highland Technology Inc

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jlarkin at highlandtechnology dot com

Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators

Apparently, some of it is off spec, too. Dave's EEVblog slams Digikey for selling off-spec .1% tolerance resistors:

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nb

vi --the heart of evil!

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