pointers to transistor (semiconductor) curve tracer circuits/projects

Yeah I did stuff like that on the computer too. when I was 13

They say that wisdom comes with age but it sounds like you just got old.

Reply to
bitrex
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Cuz I've had such habitually positive and congenial interactions with conservatives here that I'd want to sign up for the camaraderie? Not sure what kind of codepenedent you take me for, lol. I think maybe you need better marketing. With friends like these...

Reply to
bitrex

I know some guys who took a swing to the right after their first wife divorced them/cheated on them, is that what you're angling at?

I can't personally think of a sillier reason to change anything, men my age all seem to be griping about some broad or other though as if they all shit gold or something I don't really understand it personally.

Reply to
bitrex

I bought HP 4142B source/monitor unit with 3 channels to play around and created a few simple web-based Jupyter notebooks to do the measurements.

It's relatively easy to set up to do any DC parameter measurements. The code is ugly as hell (does what I need and nothing more, works probably only for my setup), but if you're interested, I can share it.

--
mikko
Reply to
Mikko OH2HVJ

I'm not sure what kind of dittohead rube it must take to listen to a has-been actor who's just been elected to the highest elected position in the _government_ run lines like "the government is the problem" and not immediately run and get the pitchforks and tar and feathers treatment for them, are they talking about some _other_ government???? Thanks for the heads up, Mr. Hoenst Abe! Gosh!

Reply to
bitrex

I bought one of these:

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It is a 4-channel SMU controlled over USB2, if you add the necessary power supplies and heatsink. That one only goes up to 80mA per channel but there are similar chips that go above an amp, but only one channel per chip. Strangely they tied the force and sense pins together on the eval board, but that should be easily fixed with a scalpel and some fine wire. I could make my own board, but in quantity of 1, I could not buy the parts for the price of that eval board.

Unfortunately the supplied software is just enough to show that it works and not enough to make it a usable lab instrument. I plotted the I-V curve of a LED with it but more than that would require some new software.

If someone did make a board with that chip, write some nice software, maybe add some isolators in the digital signal path, and put it in a box with power supplies, I think it would be pretty handy, e.g. for fitting SPICE models to actual transistors and stuff like that. I think it would be a marketable product, even if not as good as the HP / Keysight / Keithley versions.

Reply to
Chris Jones

I was never a hippie or communist myself but doesn't surprise me the radical left and radical right in the US are kissing cousins. it's called "I'm an attention-seeker please pay attention to me"

Reply to
bitrex

Tektronix made very good curve tracers, 575, 6 and earlier models. A worthwhile addition to any lab, but quite expensive now. Have a Fairchild Model 6200-B here in the lab. Not often used, but a real time saver when it's needed.

Chris

Reply to
Chris

You seem to be impuning 'his generation' for the 'lack of "real values" to sell', forgetting that it was our generation's responsibility to install those "real values" for them all to sell in the first place. :-(

It's not entirely our fault but it's a complex story involving technological developments that allowed our "Golden Rulers" to shape society through commercial and political propaganda so as to turn the consuming masses into the cash cow resource that it is today.

As I said it's a *complex* story but that's what seems to be at the core of Humanity's problems today. I have my own hypothesis as to how Humanity's problems will ultimately be resolved but since it's in that class of hypothesis known as "Conspiracy Theory", I shan't bore you with its gory details. :-)

--
Johnny B Good
Reply to
Johnny B Good

My late father was a WW2 combat veteran (I'm the youngest of four) not some shit-talking fake ass "tough guy" never-served as the leadership of the Right appears to be full of now. I think I'll be okay.

Reply to
bitrex

the hustle such as it is is not particularly sophisticated, Trump is the best friend the military-industrial complex has ever had, his role is to transfer as much money to billionaires as possible and in turn they will spend millions and billions to keep him, or a guy like him, in power as long as possible.

All you have to do to impress about 50% of Americans is just tell them you're going to give their money to billionaires instead of a black man and they'll love you forever. Easily-played dupes and rubes, like taking candy from a baby, really.

The Potemkin village will eventually collapse, however, and the Trumps and Waltons and Peter Thiels will get while the getting's good. And if you thought Hillary Clinton was bad wait until you see the true terror of the New Left that will drop in to fill the void; any duffy old MAGA-boomer without the scratch to escape to New Zealand with the billionaires and unfortunate enough to remain behind will be torn to pieces.

And probably me too, by association. Thanks assholes I kinda liked it here.

Reply to
bitrex

On Sun, 28 Oct 2018 21:08:18 -0400, bitrex wrote: \

Cassette decks? Why?

--
John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  
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Reply to
John Larkin

Don't ask me man, I went completely solid-state ages ago I don't even own any CDs anymore. People are peculiar about their dumpy ol' Onkyos which need constant maintenance with their very-impressive-for-the-time

75dB SNR or whatever. I assume that some of them have critical sections in say the pickup amps which require low noise or matched transistors but it's also been ages since I've worked on one

There's some stuff from the past that's worth preserving but some shit is best left in the past like vinyl and cassettes they were never that great.

Reply to
bitrex

Oh and Newt Gingrich is another example

Reply to
bitrex

@bitrex You are either a troll or had way too much coffee. GIve it a rest man.I have some high end audio gear from the 80s and I do some repair for friends/clients. I also do format conversions for myself and other ppl. I posted a question and 60% of the drivel that flowed is totally unrelated or begged the question about usefulness. I always thought that an IQ test should be given to ppl before they got an on-ramp to the net. Most would fail the test. I don't care about your technology views, your likes/dislikes, or your perspective on audio or electronics, your political view, or what your father did or did not do. Mine was a WWII vet - fighter pilot but has nothing to do with the question I asked.

Why a cassette deck? I am repairing one for a friend. He and I both have a Nakamichi 1000ZXL. It appears his preamp died. I didn't challenge him as to why he *still* uses it...to each their own. take a back seat, shut up, and enjoy the ride, or leave.

Reply to
three_jeeps

Thank you, I know that. Thermal properties arnt my concern. J

Reply to
three_jeeps

Yes, I know, I mistyped - thanks I agree with you about the circuit clues. Since my background is math/control theory and hardware/digital architect (as in design of CPUs), my analog skills have gotten a bit rusty. If I have some questions, perhaps I can bounce them off you privately? Thanks J

Reply to
three_jeeps

You sound obnoxious. This is an unmoderated newsgroup, and we discuss electronics. If you want paid consultants, you'll have to pay for them.

If power doesn't matter, there are generic gumdrop NPNs and PNPs and they are all pretty much the same. Casettes are noisy all by themselves, so the transistors won't matter.

I think there is a reason that people like Tek used to sell curve tracers and transistor testers, and don't any more.

I'd like a box that characterizes RF fets (phemts, SiC, GaN) for both DC specs and capacitance, but we do that other ways now, and wouldn't pay a lot for a dedicated box.

--
John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  
 Click to see the full signature
Reply to
John Larkin

Keysight has a curve tracer, the B1505A Power Device Analyzer. It's around $80K.

We have a couple of their SMUs, which can be programmed to do curve tracing, and lots more.

--
John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  
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Reply to
John Larkin

Am 29.10.18 um 01:46 schrieb snipped-for-privacy@gmail.com:

I have bought this one, since I don't want yet another boat anchor and want the results on my disk. No more screen photos. Price was so that I could survive the loss.

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It seems to work; the documentation is a hard to understand pidgin.

Sometimes there are unexpected results, like in one of the

plots where the drain current goes suddenly into saturation

for no reason.

Might be operator error, can't tell easily from the docs.

These plots have been done with it:

<
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> and left/right.

regards, Gerhard

Reply to
Gerhard Hoffmann

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