Jon Noring wrote:

Robert Casey wrote:
Patrick Turner wrote:

Happy number crunching, but I prefer late nights with a soldering
iron & cro.

I number crunch (via simulations) first (to filter out the bad ideas
that are doomed to perform poorly) and then plug the soldering iron
in....

As a mechanical engineer with project management experience, we always
first brought in the number crunchers for proposed designs before we
went and built anything, big or small. Even though we recognized that
simulation has its flaws, so one should not blindly accept the
results, the models were sufficiently accurate that it at least put us
in the right ballpark before we went out and built something.

I'm glad bridges are designed and built with this process, and not
Patrick's process.

Unfortunately, you have guessed wildly at what my methods really are.

I crunch pages full of numbers before I actually solder a single joint.
I would have 200 exercize books full of sketches and drawings of all sorts
of things, and pages
of calculations, and my folder which contains my summary of useful
formulas is at least
twenty handwritten pages, taken from many sources.
I should throw all these out, to save room in a cupboard, but sometimes I
return to look,
and I don't have a nagging woman to tell me what I must throw out....

Before I took up electronics seriously, I trained as a carpenter who did a
Building Certificate course
over 5 years at night school. I spent 25 years constructing buildings, and
then had another
15 years as a design and construction contractor.
At night school, when I didn't fall asleep in class,
they slowly taught me how to design simple bridges and retaining walls,
and dams,
and multi-story buildings, and had I had the job of designing the trade
centres in NY,
they might be still standing, with repair work about completed by now,
because I don't like
flimsy design, or ideas.

So if you ever buy a house which I'd worked on, have no fear, it won't
collapse.

My website is full of formulas.



Now the question is how accurate are the simulations of circuits
which include factors for real-world (e.g. non-linear) performance?

Well judging by the success of the space mission to Saturn and its 31
known moons,
there is a lot to be said for simulation, and accurate calculations.

I wonder about God though.

They say he made a sheila, and left a little hole,
Then he made a bloke, and gave him a little pole.

Somehow these creatures of the mud got together, and each version have
been
trying to get the hang of life ever since, and in doing so are rooting up
this planet in a way that's worse than when one of God's tradgectory
simulations went awry,
and an asteroid hit the earth, to give the huge lizards a rotten surprize
about the weather.

We are left wondering about God, who the scientists say couldn't have
existed
before the Big Bang, but I ask these morons "but what was there before the
BB?"
and they haven't the feintest idea.

Now you should remember the COWPAT formula.

COWPAT = chance of working perfectly any time =
1 divided by N squared, where N is the number of things you have to
have taken into consideration for something to turn out right.

So if you have 3 basic numbers wrong, picked the wrong tube to plug in,
had a blue wiith the missus the night before, and got drunk,
and your soldering iron fused this morning, you have 5 crook things,
and so the chance of finishing the latest IF amp stage by midnight is
1/25.

God had rather a lot of things to consider, so COWPAT virtually = 1 /
infinity, or 0.


Patrick keeps saying to get out the soldering gun and see how things
turn out, which I find perplexing since I assume the circuit
simulation codes that exist today are quite powerful.

But I don't need to spend a month of sundays to learn to drive simulators.

I can simulate well enough in my brain for a simpe thing like a detector.

It would not
surprise me if many commercial electronic circuits are first
designed entirely by computer using simulation and optimization
techniques, then prototypes built for final tweaking and testing.

Nearly all things are now designed by simulation.
A computer works it all out.


But there comes a time in a man's life where you develop a feel for an
idea,
knowing the capabilities of the elements at hand, and presto, you make
something half decent
without *too much* calculation.
Its a bit like playing chess.
Deep Fritz, the computor, can beat Kasparov, but DF has to make
perhaps billions of calculations and simulations before he can decide
where to move a pawn.
Kasparov, on the other hand takes a look at the board, thinks for awhile,
and makes
a move.
Its only in the last few years that puters developed enough power and
speed to beat the best men,
and both are essential with chess because its a timed game.

Kasparov will never be able to think like DF, and calculate and plot the
same way,
he'd take 20 years to do one move.
Picasso had this brilliance with a canvas, and probably was hopeless with
calculations and
simulations. He just "had it".

Alas, my friend here who has been our town chess champion a few times
will beat me at the game when he gives me 10 minutes on the clock
and he has set his clock for 1 minute.
He is utterly helpless with any sort of tool used to do anything real.
His ex wife and students gave him a nervous breakdown,
and he had to give up his career as a math teacher.
But at chess he is something else, he soars above the rest of us at the
cafe.
I don't like playing him much, its like being beaten up by a thug.

When you browse the pages of the last 50 years of magazines like
Wireless World which later evolved into Electronics World,
you see the evolution of some very gifted guys who are far more able than
I to
contemplate ideas, and bring electronics from what it was in 1954
to what it is now, bleeding incomprehensible for us poor mortals.

Did the fathers of the PC ever decide they had to make a detector better
before moving on?.
Nope, they probably were bored ****eless by radio, since it wasn't
interactive enough to warrant their attention.
Even bright geeks are emotional!

Simulation saves an enormous amount of calculation time with modern
circuits.
Computers design computers, we just give them the basic functions they
have to
perform, and leave them to it, and we get other computers to iron out any
bugs.
Some of the boffins in charge are bright enough to have some alarmingly
clever
insights as to why a persistant bug exists in a given prototype, and the
human's
way of thinking intuitively combined with the machine way of thought is
going
to build a future existance for our species which is utterly unimaginable
at present.

Clashes between men, and computers like HAL, in 2001, are unlikely.
And it is cheaper and probably more effective *not* to send
men on a Saturn mission, because men are complex, and have to eat,
and poo, and get along, all problematic on long space flights.
A man is too complex, like an output transformer, to ever simulate
correctly.
So there are no output trannies, or men, on the Saturn jaunt.

But if there was a good supply of oil out there,
maybe the US would send the troops to secure it.

They might find a billion times what Earth already has,
and that would spell catastophe for us, because we can't afford to
fit our sky with all that smoke.


Jon Noring

Patrick Turner.