On Mon, 16 Aug 2004 04:00:56 +0000 (UTC), "Reg Edwards"
wrote:

Paul,

I could have been even richer if I'd charged for all those computer
programs. But I have been much happier just by producing them instead of
setting up a waste-of-my-time sales and marketing organisation. But it's a
fact I never realised at the outset how popular they would become. I was
under the impression I was a late-comer to the field. But it seems I was
not. I was perhaps the originator of this type of program.

And I am confiding in you, even now, only because I am half-way down a
bottle of Californian medium-sweet white. Must keep international relations
in good order.

Well you're doin' a great job, Reg. Keep it up! What's the next
program you've got in mind to write? And which language to you
generally use for this purpose?
--

"What is now proved was once only imagin'd." - William Blake, 1793.

Anyone got any high-current/low-voltage horror stories they'd care to
share?

I friend who is a power IC developer told me about FETs being blown up by
the enery stored in the self inductance of the IC bond wire.

Wim

Paul wrote -
Well you're doin' a great job, Reg. Keep it up! What's the next
program you've got in mind to write? And which language to you
generally use for this purpose?

================================

Paul, what makes you think I do a great job? Nobody ever tells me. It's not
just idle curiosity. I'm not fishing. Feedback needed.

I always have several programs on the go at any point in time. Some have
lasted, on and off, for years. But little to do with complexity. More to
do with reliability and freedom from bugs.

I have an unfinished program which calculates the L and C values of a
parallel tuned circuit. It can be connected in an antenna wire to resonate
it to two frequencies. It is not a trap. The circuit's resonant frequency
doesn't matter very much. But on the low side of resonance it behaves as an
inductive loading coil and on the high side it behaves as a capacitance
load. The antenna becomes resonant at one frequency below the wire's natural
frequency, and at another frequency above the wire's natural frequency.

Unlike use of a trap, at both frequencies the wire radiates over the whole
of its length. Furthermore, at its lower resonant frequency, the wire is
shorter than a 1/4-wavelength.

I do not claim to have invented the arrangement. It has been previously
discussed on a newsgroup. But I doubt if the L and C values have been
explicitly calculated before.

I hesitate at making the program available to all and sundry for ever more,
because I am unable to erect an actual antenna to prove the calculations
correct. Although I am reasonably confident they are correct.

I use Pascal source code. Its an old language and you can't teach an old dog
new tricks. But programming languages have settled down. There's little
further room for improvement. I like Pascal because it is disciplined and
structured. There's no such thing as a "Go-to" command as with BASIC. The
compiler won't allow you to make logical mistakes. The quality of a program,
the finished working product, doesn't have much to do with the language
used. Chinese is just as good as English.
----
Reg, G4FGQ

Paul Burridge wrote:
On Mon, 16 Aug 2004 00:37:32 +0000 (UTC), "Reg Edwards"
wrote:


Being in the Far East, the anti-radar defence rumour, spread by the Germans,
that exposure to radar beams caused sterilisation to radar mechanics had not
reached me.

Anyway, as my wife at intervals some years later allowed me to think, I
eventually became the father of 5 children.


Perhaps you shoulda stood a bit closer to the waveguides, Reg. You'd
have been rich by now without all those kids. Plus you might even have
grown an extra brain. ;-)
Hey there was this radar tech in the army who used to sit near the
big dish in the winter to keep warm. One day they increased the
radar transmitter power 10 fold but this tech wasn't informed.

Let's just say he won the 'Darwin' award for a job 'well done'

On Mon, 16 Aug 2004 21:42:56 +0000 (UTC), "Reg Edwards"
wrote:

Paul wrote -
Well you're doin' a great job, Reg. Keep it up! What's the next
program you've got in mind to write? And which language to you
generally use for this purpose?

================================

Paul, what makes you think I do a great job? Nobody ever tells me. It's not
just idle curiosity. I'm not fishing. Feedback needed.

You make a worthwhile overall net contribution to the hobby, Reg. Your
programs save untold people an awful lot of time and f*cking about
with the kind of calculations that typically invite careless errors
and torn-out hair. I regularly visit your site and grab what I can!
Anyone with any sense would!
Will that suffice? ;-)
--

"What is now proved was once only imagin'd." - William Blake, 1793.

Behold, Wim Ton signalled from keyed 4-1000A filament:

Anyone got any high-current/low-voltage horror stories they'd care to
share?

I friend who is a power IC developer told me about FETs being blown up
by the enery stored in the self inductance of the IC bond wire.

Wim

That's why FET is known by many to stand for Fire Emitting Transistor ;-)

--
Gregg t3h g33k
"Ratings are for transistors....tubes have guidelines"
http://geek.scorpiorising.ca

On Tue, 17 Aug 2004 05:39:28 GMT, Gregg wrote:

Behold, Wim Ton signalled from keyed 4-1000A filament:

Anyone got any high-current/low-voltage horror stories they'd care to
share?

I friend who is a power IC developer told me about FETs being blown up
by the enery stored in the self inductance of the IC bond wire.

Wim

That's why FET is known by many to stand for Fire Emitting Transistor ;-)

Not so much your GP FETs, but power MOSFETs, certainly. They do tend
to go 'pop' quite spectacularly.

--

"What is now proved was once only imagin'd." - William Blake, 1793.

In message , Paul Burridge
writes
Hi all,

Anyone got any high-current/low-voltage horror stories they'd care to
share? You know; where your messin' about with a car battery or
something like that and forget to take your watch off or whatever.

p.
Although I knew how crowbar protection worked on PSUs I was shown in a
dramatic way when I used a bench PSU to charge a car battery, for what
ever reason the crowbar operated and put a short across the battery,
lots of bright white wire and smoke for a few seconds.
A colleague of mine was a vehicle radio fitter and always wore metal
watch straps, until the day one bridged a battery supply and chassis. He
always wears a leather strap now and takes his watch off before working.
How more of us are not maimed or killed I'm not sure.
--
Bill

Back in the 60's I recall being at a party where everyone had too much
to drink and some YL's car would not start. The 'guys' went out to help
and checked the battery water level. The guy doing the checking could
not see as it was dark and asked for light. He was talking about a
flashlight and a helping hand showed up with a Zippo lighter. The
battery exploded! Very lucky none were killed or blinded.

On Tue, 17 Aug 2004 05:39:28 GMT, Gregg wrote:

Behold, Wim Ton signalled from keyed 4-1000A filament:

Anyone got any high-current/low-voltage horror stories they'd care to
share?

You should see a 440 RMS working volt 50,000 Joule MOV on a 600 amp
440 line that has received an over voltage spike.

The only thing left are the connecting wires and they are pointed
straight out. They are blinding if you happen to be looking at one
when it blows, or deafening if you are near. They'd put any 12 gauge
shotgun to shame.

These things are about 3 X 4 inches and just shy of an inch thick.
Used across a pair of 1200 VAC 1200A (as I recall) SCRs (Thyristors)

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
I friend who is a power IC developer told me about FETs being blown up
by the enery stored in the self inductance of the IC bond wire.

Wim

That's why FET is known by many to stand for Fire Emitting Transistor ;-)