Re: CO2 Funny

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:v2uhs7$39s6m$1@dont-email.me...

On 26/05/2024 4:38 am, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:v2na16$1nvei$1@dont-email.me...

On 23/05/2024 3:52 am, john larkin wrote:

On Wed, 22 May 2024 18:10:58 +0100, Pomegranate Bastard
<pommyB@aol.com> wrote:
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...

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John Larkin doesn't seem to 'design" anything. He throws together the stuff he sells like every other tinkerer.
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Why does that matter to you so much?
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I have two books in front of me.
One is "Introduction to Solid State Physics, C. Kittel"
The other is "FET Circuits. Rufus P Turner"
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If I open the physics book at a random page I find a contour integral.
I wasn't bad at math and can handle contour integrals but it is also true that I grew up in a very practical electronics
environment
where getting things working was way more important than understanding every little detail of the theory of how they worked.

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I got into electronics while a I was doing a Ph.D. physical chemistry. Win Hill started a Ph.D. in chemical physics, but had better
advisors.

Getting things working is always important, but understanding the detail of what's going on can be vital to getting them to work
well.

So both of these are needed if you want the best design.

When I was working at Cambridge Instruments (1982-1991) it was mostly on projects,but between projects I'd get stuck with "mods"
which was looking at what production was complaining about and reworking the circuit that they were complaining about to make it
better behaved. A lot of that was correcting the original designer's minor mistakes.
One of them wasn't all that minor - somebody has used a 741 in a place where it's pop-corn noise got amplified to the point where
the heaters in our GaAs single crystal puller were effectively pulse width modulated with a cycle time of about a minute or so.
Replacing the 741 with a marginally less ancient part with a pop-corn noise spec meant that the heaters ran continuously at
something like 30% of full capacity.
It made the operating environment a lot more peaceful and may have produced more-nearly-strain-free single crystal GaAs.

I could write a book about what I encountered when I left academic study and started designing electronic
products for production. I had the advantage (or disadvantage?) of many previous years of practical
experience of circuits designed by others and some designed by myself but not for volume production.

Before starting work I did a course in Power Electronics.
The lecturer used many thyristors but the gate was never connected to anything.
I wanted to ask whether you could just connect the gate to a logic output but never did.

After starting work it was clear to me that most of the issues I encountered arose because they weren't important to academia
so none of the textbooks covered them.

I encountered boards with none of the power pins on the chips connected to anything.

I also remember bringing a book into work and one of the experienced designers was amazed that such a book existed.

Most of the electronic circuit texts available at the time which were used in academia where excessively detailed
and about as useful as the average Wikipedia page.

This book was different, it actually covered subjects such as why you shouldn't expect the output of an op amp to go above its +
supply rail
and why a circuit wasn't likely to do much if the op amp was part of the circuit which produced its own supply rail.

I'll leave you to guess which book that was. Shame that the current edition is the last.

If I open the FET book at a random page I find a circuit which may be usable as the basis of something I want to "design".
This isn't true of the physics book but that doesn't mean I don't find it to be interesting or useful knowledge.
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Human psychology obviously plays a big part in electronics design as it does in electronics designers.
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It does seem to be a trait of many (not all) electronics designers that if another designer isn't doing it the way they would do
it
then they must be doing it wrong.

It usually takes a while to work out why they did it that way, and it's pretty much essential to spend that time before you start
fiddling with the circuit. That wasn't true of the guy who'd put in the 741. He was very much in the John Larkin "if it sort of
works, ship it" camp.

Which of John Larkin's products have you purchased and tested and what improvement
do you think should have been made before it was shipped?

Management liked him because he was quick. Production was less enthusiastic.

Management likely expected that problems would be found which would have to be dealt with at a later time.

Would you be kind enough to give your opinion of John Larkin once per month instead of twice per day?

When he starts claiming to do electronic design once a month rather than twice a day.

I still don't see why it matters so much when the two of you are in different countries and, correct me if I'm wrong,
you've never used or tested any of JL's products.

You can't deny that JL has a successful business.
Whether his business would be more successful if he adopted different design techniques is not something I wish to go into
because it simply doesn't matter to me.

--
Bill Sloman, Sydney