engineering is hard

You applied for entry for a degree course to a Faculty , Arts, Law, Science , Engineering etc. They guy I knew changed course during the first term

Switching courses in the same Faculty, was probably easier. Engineering was the same course for all disciplines 1st year. Maths Physics and Chemistry mostly.

It had and has great departments of civil engineering and medicine.

But it ranked near the top, or maybe actually #1, in party schools, which attracted kids from all over the country. When I was there, a

The undergrad EE education was OK, the standard physics and circuit theory and signals-and-systems and communications theory. We also had to take two sessions of Electrical Machinery, which seemed silly at the time but I'm glad I did it.

Engineering Design Analysis was the first intro course. About dimensional analysis and common sense. That was wonderful. The other fabulous course was Signals and Systems. And Beginners' Tumbling.

Introduction To Girls wasn't a formal course at Tulane but that was great too.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

I've never heard of either.

Pity that none of it sank in.

Your idea of common sense lets you think that Donald Trump has it.

Did you know which was which?

I should have met my wife when we were undergraduates at Melbourne - fortunately we never met until we'd had time to mature. I'd got my Ph.D, and she'd got her MA by then. She then went of to Texas to do a Ph.D. in Psycholinguistics and I went to England to do a post-doc,and we ended up getting together permanently in the UK. That took some nine years.

Oh yes I'd noticed that but it works both ways. I don't think highly of the way you insist that you know better than anyone else. I also don't think highly of the way you are quick to tell someone else that their grasp of reality isn't great. Or the way you like to tell other people what they think.

I don't care much for emitter coupled monostables myself. It was probably Rufus Turner's FET circuits where I first saw a circuit for one. So I'm happy to ignore the fact that people have been using it since then, or before then.

But, as usual, you didn't explain why. I didn't put in any provision to level shift the output - my 1979 paper describing a fast. but more conventional, monostable used a transmission line transformer, which was pretty bizarre, but fine in the application. Not knowing what kind of output you wanted or your power supply constraints, I didn't bother to elaborate the Spice model to include one. It wouldn't be difficult.

And you didn't complain about it being a bizarre version of an emitter coupled monostable - you claimed that it was just a gain of ten amplifier, with the implication that it wasn't a monostable at all.

For the fast input pulses that you used, with carefully teased levels, as I recall, it amplified and the positive feedback was too slow to do anything.

But repost it and we can discuss it.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Everybody needs a starter wife.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Here we have a big University (Stanford, UC Berkeley, Cornell) that has schools or colleges within it, like the school of engineering or the business school or the school of fine arts. There is no big barrier against changing schools.

Universities often have satellite campuses, and again there is no big barrier to taking classes here and there or moving around.

We had a lot of EE labs, but we tended to bail early, right after the instructor left, and fake the lab reports.

Neither work nor school is efficient after eight hours a day, or maybe six. Some people conjecture four.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Not a great idea. Your fertility is high, and you are likely to have kids before you realise that you can't sustain a relationship with your "starter" wife.

The human brain is fully grown by the time you are about eighteen, but it doesn't get edited into it's final form until you are about 25.

I was lucky in that my first serious relationship fell apart after a couple of years, while I was still working on my Ph.D. I didn't feel all that lucky at the time, but getting the Ph.D. was a useful distraction.

On 5/11/2025 3:05 am, john larkin wrote:

There wasn't anything carefully teased about the levels. It was much the same pulse that I'd had to stretch further back in 1979.

The full-width at half max of the input pulse was about 400psec. The output pulse had FWHM of about 1nsec. Push up C1 to 10pF and it goes up to 2nsec.

That's not "nothing".

Perhaps.

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google solve differential equations

Gosh, everybody else is wrong.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

I don't make a habit of that, but on those rare occasions when I do know better than some specific person I won't shy away from making the point

Pity about that. I do try to avoid being that undiplomatic, but some people don't respond to subtle suggestions.

It's has it's defects. You can't use the classic version to produce a

Roughly speaking yes, but the edges can sometimes be blurred.

It is virtually impossible to get into Law, Medical, Vet or Dentistry by any other means than direct acceptance by the department.

Unpopular under-subscribed courses are less fussy about who they accept.

Hard sciences, medical and engineering are expensive to teach because of complex practicals and laboratory space required.

More or less. I applied to do chemistry when I went to university but then jumped ship to physics when I saw their fabulous new laboratory. The university I went to actually allowed you to choose a specialism in the second year from a wider range of possible Natural Sciences.

Typically at school in the UK there was only Biology, Chemistry & Physics. First year courses at my university included in addition Crystalline Materials, Biochemistry, Geology, Pathology, Pharmacology, Earth Sciences and a few others I have probably forgotten.

The most extreme jump that I can recall was someone accepted to read chemistry and changed to theology. Most universities in the UK don't offer much flexibility to move between departments at all. Moving between the science faculty and humanities (or vice versa) was exceptionally rare.

When I went to university in the UK it was very much choose your subject first and then look for the universities with the best department for that subject (assuming that you were good enough to make the grade).

You basically pick a list of 5 and go visit any that want to see you. It narrows down to a choice of two later (before the exams) - the one you really want and an insurance policy. Current rules are here:

In the UK it can do if you are any good at it and a supervisor wants to take you on. A known quantity often being preferred to a pig in a poke.

Our maths for scientists course was pretty extreme. Vector calculus was taught in the first term and it went onwards and upwards from there.

The mathematics for theoretical physics course was even worse - designed to put off anyone who might not make the grade in the first week!

Lab work was an afternoon a week in each science subject and you were expected to study 3 science courses and maths in the first year. The practical exams at the end of the year required knowledge of experimental techniques taught in the practical classes.

Specialising was really only in the second and third years.

No. You are. You can use differential equations to solve problems, but what google pulls out doesn't mean what you'd like it to mean.

I can't imagine any reason to make a discrete transistor monostable these days.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

It's a bad habit. I didn't fake my lab reports, but found out later that they had had an uncanny habit of reappearing years later in other other peoples hand-writing.

Efficiency is just output as a proportion of input. You've got measure both in terms of same units. You can be more productive if you work in short bursts, but what you put in is your time, and what you deliver is something that somebody else can read or look at or use.

What you probably mean is that people are more productive if they work in short bursts, but if you lose track of what you are doing between bursts of work, you will probably end up skipping one or more of the tasks you needed to complete.

That wasn't really the case in Scottish universities upto at least the

Fast integrated circuits tend to run at rather low voltages.

The electron beam blanking systems in Cambridge Instruments electron microscopes needed more voltage swing than you could get out of a fast integrated circuits.

Our stroboscopic electron beam tester needed +/-7.5V to keep the electron beam far enough away from our 100 micron diameter aperture, and we wanted to get it back to the aperture for just 0.5nsec.

The electron beam microfabricator was less demanding. The original electron beam resists were pretty insensitive and we needed a 200nsec dwell time to expose them. Then we got a faster resist, and I had to rework several bits of the machine to run at 10MHz rather than 5MHz, and nobody wanted to rework the column to let me get the beam blanking electrodes as close to the electron beam as the were in the electron beam tester.

I ended up delivering +/-60V unblanking pulses about 100nsec wide.

Your laser modulators will be even worse.

In message <10ed7ne$3o5rl$ snipped-for-privacy@dont-email.me, Don Y snipped-for-privacy@foo.invalid writes

Pretty much. However this was a considerable time ago .There was a little bit of flexibility . I go to do Astronomy as a subsidiary subject in 4th year as I needed one . The Civil Engineers were allowed this to teach them spherical trig. I really enjoyed it. I suppose if I'd asked to do Mediaeval History, it might have not gone down too well.

Brian