pointers to transistor (semiconductor) curve tracer circuits/projects

On Mon, 29 Oct 2018 01:34:41 -0400, bitrex <user@example.net> wrote:

>On 10/28/2018 11:00 PM, Jeff Liebermann wrote:
>> On Sun, 28 Oct 2018 18:33:48 -0700 (PDT), jurb6006@gmail.com wrote:
>> 
>>>> ""youth", in quotes I'm just shy of 40"
>>>
>>> Wow, that explains why you're not conservative. You will be
>>> in about ten years, and don't worry, it doesn't hurt.
>> 
>> Y're right.  I'm just short of 71.  I started out as a radical
>> leftist, commie pinko, anti-everything, chronically protesting, hippie
>> freak:
>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-06.html>
>> Fast forward about 40 years, and today I'm an arch conservative,
>> somewhat reactionary, right leaning, registered Republican, member of
>> the establishment:
>
>Woah, how unusual.

Not really.  Many of my friends followed approximately the same path.
Some saw the problems with the idealism of the 1960's and switched
early, while others got the clue after they accumulated some
responsibilities.  I know a few that still look like they're
protesting something, but vote and put their money on conservative
candidates and policies.  My transformation was rather unusual:
<http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-wolf.html>

Patience.  Your turn will come.  Best you prepare yourself for the
inevitable metamorphosis.

>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-08.html>
>> It can and probably will happen to you.  Resistance is futile.

>You don't have to explain to us that the "baby boomer" generation were 
>sellouts with no real values who'd gladly hawk their souls for ten 
>bucks. We know, already ;-)

Ok, I won't explain.  You already have all the answers.  I'll give you
credit for recognizing that us baby boomers had "real values" to sell,
while your generation seems to lack any values worth selling.

11PM and I forgot to eat dinner.  Argh.

-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

On 10/29/2018 02:09 AM, Jeff Liebermann wrote:
> On Mon, 29 Oct 2018 01:34:41 -0400, bitrex <user@example.net> wrote:
> 
>> On 10/28/2018 11:00 PM, Jeff Liebermann wrote:
>>> On Sun, 28 Oct 2018 18:33:48 -0700 (PDT), jurb6006@gmail.com wrote:
>>>
>>>>> ""youth", in quotes I'm just shy of 40"
>>>>
>>>> Wow, that explains why you're not conservative. You will be
>>>> in about ten years, and don't worry, it doesn't hurt.
>>>
>>> Y're right.  I'm just short of 71.  I started out as a radical
>>> leftist, commie pinko, anti-everything, chronically protesting, hippie
>>> freak:
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-06.html>
>>> Fast forward about 40 years, and today I'm an arch conservative,
>>> somewhat reactionary, right leaning, registered Republican, member of
>>> the establishment:
>>
>> Woah, how unusual.
> 
> Not really.  Many of my friends followed approximately the same path.
> Some saw the problems with the idealism of the 1960's and switched
> early, while others got the clue after they accumulated some
> responsibilities.  I know a few that still look like they're
> protesting something, but vote and put their money on conservative
> candidates and policies.  My transformation was rather unusual:
> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-wolf.html>

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

> Patience.  Your turn will come.  Best you prepare yourself for the
> inevitable metamorphosis.
> 
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-08.html>
>>> It can and probably will happen to you.  Resistance is futile.
> 
>> You don't have to explain to us that the "baby boomer" generation were
>> sellouts with no real values who'd gladly hawk their souls for ten
>> bucks. We know, already ;-)
> 
> Ok, I won't explain.  You already have all the answers.  I'll give you
> credit for recognizing that us baby boomers had "real values" to sell,
> while your generation seems to lack any values worth selling.
> 
> 11PM and I forgot to eat dinner.  Argh.
> 

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

On 10/29/2018 02:04 AM, tabbypurr@gmail.com wrote:
> On Monday, 29 October 2018 05:34:47 UTC, bitrex  wrote:
>> On 10/28/2018 11:00 PM, Jeff Liebermann wrote:
>>> On Sun, 28 Oct 2018 18:33:48 -0700 (PDT), jurb6006@gmail.com wrote:
>>>
>>>>> ""youth", in quotes I'm just shy of 40"
>>>>
>>>> Wow, that explains why you're not conservative. You will be
>>>> in about ten years, and don't worry, it doesn't hurt.
>>>
>>> Y're right.  I'm just short of 71.  I started out as a radical
>>> leftist, commie pinko, anti-everything, chronically protesting, hippie
>>> freak:
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-06.html>
>>> Fast forward about 40 years, and today I'm an arch conservative,
>>> somewhat reactionary, right leaning, registered Republican, member of
>>> the establishment:
>>
>> Woah, how unusual.
>>
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-08.html>
>>> It can and probably will happen to you.  Resistance is futile.
>>>
>>>
>>
>> You don't have to explain to us that the "baby boomer" generation were
>> sellouts with no real values who'd gladly hawk their souls for ten
>> bucks. We know, already ;-)
> 
> you'll learn
> 

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...

On 10/29/2018 02:04 AM, tabbypurr@gmail.com wrote:
> On Monday, 29 October 2018 05:34:47 UTC, bitrex  wrote:
>> On 10/28/2018 11:00 PM, Jeff Liebermann wrote:
>>> On Sun, 28 Oct 2018 18:33:48 -0700 (PDT), jurb6006@gmail.com wrote:
>>>
>>>>> ""youth", in quotes I'm just shy of 40"
>>>>
>>>> Wow, that explains why you're not conservative. You will be
>>>> in about ten years, and don't worry, it doesn't hurt.
>>>
>>> Y're right.  I'm just short of 71.  I started out as a radical
>>> leftist, commie pinko, anti-everything, chronically protesting, hippie
>>> freak:
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-06.html>
>>> Fast forward about 40 years, and today I'm an arch conservative,
>>> somewhat reactionary, right leaning, registered Republican, member of
>>> the establishment:
>>
>> Woah, how unusual.
>>
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-08.html>
>>> It can and probably will happen to you.  Resistance is futile.
>>>
>>>
>>
>> You don't have to explain to us that the "baby boomer" generation were
>> sellouts with no real values who'd gladly hawk their souls for ten
>> bucks. We know, already ;-)
> 
> you'll learn
> 

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.

jjhudak4@gmail.com writes:

> I have made (in the past) the typical transistor curve tracer that
> shows the curves on a scope - cute but not precise enough for my
> intentions. I am more interested in a lab type instrument.

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

On 10/28/2018 09:33 PM, jurb6006@gmail.com wrote:
>> ""youth", in quotes I'm just shy of 40"
> 
> Wow, that explains why you're not conservative. You will be in about ten years, and don't worry, it doesn't hurt.
> 

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!

On 29/10/2018 18:36, Mikko OH2HVJ wrote:
> jjhudak4@gmail.com writes:
> 
>> I have made (in the past) the typical transistor curve tracer that
>> shows the curves on a scope - cute but not precise enough for my
>> intentions. I am more interested in a lab type instrument.
> 
> 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
> 

I bought one of these:
https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/eval-ad5522.html

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.

On 10/28/2018 11:00 PM, Jeff Liebermann wrote:
> On Sun, 28 Oct 2018 18:33:48 -0700 (PDT), jurb6006@gmail.com wrote:
> 
>>> ""youth", in quotes I'm just shy of 40"
>>
>> Wow, that explains why you're not conservative. You will be
>> in about ten years, and don't worry, it doesn't hurt.
> 
> Y're right.  I'm just short of 71.  I started out as a radical
> leftist, commie pinko, anti-everything, chronically protesting, hippie
> freak:

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"

On 10/29/18 00:46, jjhudak4@gmail.com wrote:
> I find myself in a situation where I am repairing some high end audio amps and cassette decks that have house numbered semiconductors, mainly transistors as well as JDEC p/n that are NLA.
>
> I have found a few transistors that are dead and need to be replaced.  Fortunately, they are in parts of the amp where the other channel has an identical transistor.
> Having one transistor as a base will allow me to match something close to the original.
>
> I have made (in the past)  the typical transistor curve tracer that shows the curves on a scope - cute but not precise enough for my intentions. I am more interested in a lab type instrument.
>
> Basically what I am looking for is a curve tracer that has a micro attached to it that have some A/D's on them that can record the data of interest (e.g. Ib (vb), Vce, etc.
> I've considered an arduino based approach but they have the limitations of  5V max on the input for the A/Ds and don't want to scale it.
> I've looked for old Heathkit and Tek curve tracers that I could augment with a micro but they seem to be very scarce, in addition to having transistors in them that are NLA.
> I could design one myself but in all honesty, I'd prefer to find something where someone has 'plowed the ground' and at the very most, I'd have to augment it with a micro.  Yea, I am a bit lazy - the intent was to fix the amp, not develop a curve tracer....
> Thanks in advance
> J
>

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

On Sun, 28 Oct 2018 23:09:46 -0700, Jeff Liebermann wrote:

> On Mon, 29 Oct 2018 01:34:41 -0400, bitrex <user@example.net> wrote:
> 
>>On 10/28/2018 11:00 PM, Jeff Liebermann wrote:
>>> On Sun, 28 Oct 2018 18:33:48 -0700 (PDT), jurb6006@gmail.com wrote:
>>> 
>>>>> ""youth", in quotes I'm just shy of 40"
>>>>
>>>> Wow, that explains why you're not conservative. You will be in about
>>>> ten years, and don't worry, it doesn't hurt.
>>> 
>>> Y're right.  I'm just short of 71.  I started out as a radical
>>> leftist, commie pinko, anti-everything, chronically protesting, hippie
>>> freak:
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/
jeffl-06.html>
>>> Fast forward about 40 years, and today I'm an arch conservative,
>>> somewhat reactionary, right leaning, registered Republican, member of
>>> the establishment:
>>
>>Woah, how unusual.
> 
> Not really.  Many of my friends followed approximately the same path.
> Some saw the problems with the idealism of the 1960's and switched
> early, while others got the clue after they accumulated some
> responsibilities.  I know a few that still look like they're protesting
> something, but vote and put their money on conservative candidates and
> policies.  My transformation was rather unusual:
> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/jeffl-
wolf.html>
> 
> Patience.  Your turn will come.  Best you prepare yourself for the
> inevitable metamorphosis.
> 
>>> <http://www.learnbydestroying.com/jeffl/pics/jeffl/slides/
jeffl-08.html>
>>> It can and probably will happen to you.  Resistance is futile.
> 
>>You don't have to explain to us that the "baby boomer" generation were
>>sellouts with no real values who'd gladly hawk their souls for ten
>>bucks. We know, already ;-)
> 
> Ok, I won't explain.  You already have all the answers.  I'll give you
> credit for recognizing that us baby boomers had "real values" to sell,
> while your generation seems to lack any values worth selling.
> 
 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