Ernie wrote:
12 years back there was a CB'er that had a double 3-500 Z amp with
3500 volts on the plate that lived next door to me.

One day he noticed he was running about half power instead of
full bore so he popped the top of the amp and noticed one of the
wires on the tube caps (PLATE) had come unsoldered.....so
instead of turning the amp off he melted the solder a bit with his
insulated soldering iron and forced the wire back into the molten
puddle....It worked!.......Then holding a large roll of bare solder in
his hand he added a bit more to the molten solder

It didnt take him long to let go of that roll of solder in his bare
hand!!!

Something similar happened to a friend who was doing some soldering on a
power amp that was still switched on. He wasn't as stupid as that CBer
above, oh no. He had passed his amateur exams, so he knew he was working
on a "safe" part of the amp, well away from the 3kV.

Well...

He was using a whole reel of solder, and holding the end between finger
and thumb, kinda like you do. But he wasn't paying too much attention to
the rest of the reel - it slipped off his other finger, and unwound into
the amp. Guess where?

He had a nasty little burn on his thumb, and an even nastier little hole
in his shirt-front where his chest had been pressed against the case of
the amp. He's very lucky indeed to be alive.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

I seem to recall that one of the early founders of amateur radio in
the US died from a similar accident.

Details escape me, although I recall reading about it sometime last
year.

Happy trails,
Gary (net.yogi.bear)
------------------------------------------------
at the 51st percentile of ursine intelligence

Gary D. Schwartz, Needham, MA, USA
Please reply to: garyDOTschwartzATpoboxDOTcom

On Sat, 21 Aug 2004 16:11:10 +0100, "Ian White, G3SEK"
wrote:

Hi Ian,

Was it you who carried out some tests a while ago trying to simulate
the measurement of S - parameters through Spice? I know you've got a
VNA, but I'm talking here strictly about *simulation* of transistor
reflection coefficients, for the avoidance of doubt. Was that
yourself?
--

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

Paul Burridge wrote:
On Sat, 21 Aug 2004 16:11:10 +0100, "Ian White, G3SEK"
wrote:

Hi Ian,

Was it you who carried out some tests a while ago trying to simulate
the measurement of S - parameters through Spice? I know you've got a
VNA, but I'm talking here strictly about *simulation* of transistor
reflection coefficients, for the avoidance of doubt. Was that
yourself?

No.

--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

On Sun, 15 Aug 2004 12:01:14 +0100 Paul Burridge
wrote:

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

Co-worker of mine wore his nice shiny new anniversary wrist watch
(with metal band) while working around his car battery. Pushed his
hand down into a tight spot and shorted the hot terminal to ground
with the band.

He said there was a flash and suddenly the band was starting to glow.
He jerked his hand out almost instantaneously, and the watch and band
sailed across the garage, hit the wall, and crashed to the concrete
floor.

He wore a bandage around his wrist for a couple of weeks, but all he
has to show for it now is the brand around his wrist that the
watchband left behind.

I have no idea what he told his wife....

-
-----------------------------------------------
Jim Adney
Madison, WI 53711 USA
-----------------------------------------------

Â*Â*Â*Â*Â*Â*Â*Â*I'veÂ*heardÂ*ofÂ*aÂ*telephoneÂ*exc hangeÂ*painter
putting a can of paint down on the main exchange 50V
bussbars: caused quite a fire too. Another phone tech
had a fuse that blew once a week, he kept putting a
larger and larger fuse in until the wooden exchange
building burnt down.

Mark H

"Reg Edwards" wrote in message
...

But in my case I would prefer the more lax and broader definition of
Quality
: The ability to serve the intended purpose.

Well done Reg. I agree that definition fits in nicely with my (adopted)
expression which is "Fitness for use".
Terry.
PS. As an ex-Brit one of my most interesting and ironic experiences (around
1959) was trying to explain to a USAF Tech. Sgt. neighbour, of Mexican
background, the significance of the Boston Tea Party!
Sort of along the lines of, "Well actually old boy we lost that one; the US
Colonies went their own way to become the USA! Got that Carlos?"
IIRC his name was Carlos Valencia and he was married to a girl from around
New England. He fixed aircraft and I fixed his TV/Radio etc. Nice chap.

On Sun, 22 Aug 2004 12:26:33 GMT, Mark Harriss hath writ:

Another phone tech had a fuse that blew once a week,
he kept putting a larger and larger fuse in
:
:
until the wooden exchange building burnt down.

Problem solved! HI!HI!

73
Jonesy
--
| Marvin L Jones | jonz | W3DHJ | linux
| Gunnison, Colorado | @ | Jonesy | OS/2 __
| 7,703' -- 2,345m | config.com | DM68mn SK

"Paul Burridge" wrote in message
...
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.

Paul; I guess mine concerns 'zero amps'. Particularly, a motor generator
unit comprising a 48 volt 200 amp DC generator driven by a shaft coupled 3
phase 230 volt motor, which we moved a few miles. After supervising the
move, at night, I left the in charge technician and the crew to finish off
and went home to bed. Around 01.30h, I was roused by a phone call, "No
output". This unit HAD to be working by 09.30h at latest, next morning!
During the move the DC generator must have lost its 'residual magnetism' and
when restarted was putting out +9 volts instead of -48 volts and
consistently tripping the output circuit breaker when they tried to connect
it to the working equipment and batteries!
Although I had never encountered it before I had sufficient technical
background to surmise what had happened and after blowing a few fuses and
burning off a temporary lead in my hand was able to get sufficient negative
48 volt voltage onto the field winding of the unit. It recovered and was
there until all the equipment in that building was retired some 15-20 years
later.
Phew!
PS. 200 amps @ 48 volts is some 10 kilowatts, the output of one motor
generator set and there were 3 of them.

I heard of a newly installed phone exchange
generator that kept stalling when they cut it on to
the load: they pulled it all apart and checked every
part of the alternator and diesel motor with no
success.

Then one day they were trying again and these
linesmen rushed in from the pub next door shouting
and screaming: The grid in the area had been shut
down for line repairs so the immediate city block
had no electricity. They were knocking back a few
coldies when they heard the roar of the generator
and saw the lights in the pub flickering.

It seems the techs had wired it in without
relays to isolate the line input cables and were
trying to power an entire city block: no wonder it
was stalling. They were lucky they didn't fry a
linesman too.

AIEEEEE! :-o

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

Mark Harriss ) writes:
It seems the techs had wired it in without
relays to isolate the line input cables and were
trying to power an entire city block: no wonder it
was stalling. They were lucky they didn't fry a
linesman too.


There is a lot to be said for nipping in to a pub occasionally. Maybe one
could find a lot of safe linemen there.

.... Martin

While not low voltage, I remember reading in the '60s in Scientific
American an article which mentioned how many milliamps of current was
enough to be felt / dangerous / deadly, etc. It mentioned that
substantially larger currents could sometimes even be safer as they could
cause involuntary muscle contractions which would interrupt the current
flow.

The example given was of a worker at a high-rise construction site in New
York who was changing out of his work clothes at the end of his shift in a
temporary shack that also housed the site electrical power connections.
While doffing his trousers he accidentally backed into a high voltage
panel. An estimated 60 amperes passed from one buttock to the other
through muscles that immediately straightened, propelling him through the
shack and its door and into two lanes of road traffic which immediately
stopped.

Because the current didn't pass through any vital organs, he only
sustained surface burns and various bruises and scrapes though the
electrical panel manufacturer's logo is now mirror-image tattooed to his
behind.

I've *gotta* find the source of all this...

Jim Horn, WB9SYN/6

"James Horn" wrote in message
...
: While not low voltage, I remember reading in the '60s in
Scientific
: American an article which mentioned how many milliamps of
current was
: enough to be felt / dangerous / deadly, etc. It mentioned that
: substantially larger currents could sometimes even be safer as
they could
: cause involuntary muscle contractions which would interrupt the
current
: flow.
:
: The example given was of a worker at a high-rise construction
site in New
: York who was changing out of his work clothes at the end of his
shift in a
: temporary shack that also housed the site electrical power
connections.
: While doffing his trousers he accidentally backed into a high
voltage
: panel. An estimated 60 amperes passed from one buttock to the
other
: through muscles that immediately straightened, propelling him
through the
: shack and its door and into two lanes of road traffic which
immediately
: stopped.
:
: Because the current didn't pass through any vital organs, he
only
: sustained surface burns and various bruises and scrapes though
the
: electrical panel manufacturer's logo is now mirror-image
tattooed to his
: behind.
:
: I've *gotta* find the source of all this...
: Jim Horn, WB9SYN/6


60 amps though "Human flesh" will cook it well done! 15mA through
the vital organs will kill! As little as 30 microamps will cause
a severe muscle reaction and not even the sturdiest will be able
to resist movement if the current reaches 2 mA.

Roger Gt wrote:

60 amps though "Human flesh" will cook it well done! 15mA through
the vital organs will kill! As little as 30 microamps will cause
a severe muscle reaction and not even the sturdiest will be able
to resist movement if the current reaches 2 mA.


Generally true, Roger, but *time* is as important a variable as well. To
cook anything well done takes substantial energy and that's a function of
current, voltage and time. The point of the story was that the effect was
immediate, the current flow brief, and the surface was still burned.

I don't volunteer to try recreating the experiment though!

Jim Horn, WB9SYN/6

"James Horn" wrote in message
...
: Roger Gt wrote:
:
: 60 amps though "Human flesh" will cook it well done! 15mA
through
: the vital organs will kill! As little as 30 microamps will
cause
: a severe muscle reaction and not even the sturdiest will be
able
: to resist movement if the current reaches 2 mA.
:
:
: Generally true, Roger, but *time* is as important a variable as
well. To
: cook anything well done takes substantial energy and that's a
function of
: current, voltage and time. The point of the story was that the
effect was
: immediate, the current flow brief, and the surface was still
burned.
:
: I don't volunteer to try recreating the experiment though!
:
: Jim Horn, WB9SYN/6
:


I wasn't trying to paint a picture, that was the story tellers
job, I only volunteered a little information. However, I do
doubt that he got 60 amperes through his buttocks! The current
would have caused the required impulse to part with the voltage
rather early on. (:)

I actually worked in a place where they were testing nerve
stimulus devices which allowed for diagnosing whether there was
damage in some particular part of the body. As a final test they
had the technicians put needles into their arms to take a sample
reading. I passed on that one. Those poor guys ever got stopped
by the police they would have a hard time explaining the tracks.

OK, some more stupid tricks.
In Jr. High school science fair some kid
brought in a one tube radio, powered by
a 1.5v A battery and a 90 volt B battery.
Radio wasn't working so some brainiac
said 'test the batteries'. How do you test
them? Kid said he tested transistor radio
batteries by touching them to his tounge,
to taste the sour a good battery caused!!!

Well he tried that with the B battery!

PS...It was VERY GOOD!!!!!

(just how far did he threw that battery
across the room, I forgot!)

Gary S. wrote:
I seem to recall that one of the early founders of amateur radio in
the US died from a similar accident.

Details escape me, although I recall reading about it sometime last
year.

Happy trails,
Gary (net.yogi.bear)
------------------------------------------------
at the 51st percentile of ursine intelligence

Gary D. Schwartz, Needham, MA, USA
Please reply to: garyDOTschwartzATpoboxDOTcom
Russ Hall was eletrocuted by a CRT power supply
in the 30's while building an early TV receiver.

Paul Burridge wrote in message . ..
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.

Hi Paul,

Here's some to remember next time you are raising an antenna near power lines:

Guy on PCP grabs 16,000 volts and lives:

http://members.tripod.com/~StormTrooper_2/index2.htm

High Voltage Sparks and Arcs - cursor down to "Crane Tangles with a 46 kV Feeder..."

http://205.243.100.155/frames/longarc.htm

Best

Mike

: Paul Burridge wrote in message
. ..
: 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.

Yes.

On 30 Aug 2004 07:38:34 -0700, (Mike Monett) wrote:

High Voltage Sparks and Arcs - cursor down to "Crane Tangles with a 46 kV Feeder..."

http://205.243.100.155/frames/longarc.htm


Wow. Spectacular videos. I cranked up the sound for maximum effect on
the 500KV one, and after several plays, one of my destop speakers walked
off the desk and fell on the floor.

This comment reminded me of a High Current Horror Story related to me by
an older friend. In his youth he repaired radios, hi-fi systems, and the
like. One well-heeled customer had large, expensive speakers at the room
corners, with the hi-fi in the middle. He'd put the speaker wiring in
the walls. For connectors, he'd used ordinary mains AC power
receptacles, with matching cord and plug on each speaker.

When the repair was finished, my friend plugged the speaker back into
the outlet. He knew exactly what had happened the moment he plugged it
in when he heard a monstrous, deafening hum -- but even then it was too
late, the speaker was cooked. Let's see, 120^2 / 8(*) = . . . now,
that's LOUD!

Roy Lewallen, W7EL

(*) and I suspect that the speaker impedance was somewhat lower yet at
60 Hz.

Rex wrote:

On 30 Aug 2004 07:38:34 -0700, (Mike Monett) wrote:


High Voltage Sparks and Arcs - cursor down to "Crane Tangles with a 46 kV Feeder..."

http://205.243.100.155/frames/longarc.htm



Wow. Spectacular videos. I cranked up the sound for maximum effect on
the 500KV one, and after several plays, one of my destop speakers walked
off the desk and fell on the floor.

And you reminded me of something too. Not really a problem, but could
have been.

When I was working on mainframe computers in the 70's we installed a new
machine in Europe. The power for the computer was supplied by a big
motor generator with an output of 3-phase 208 V 400 Hz (or was it CPS
back then?) power to the computer. I learned from the customer that they
discovered that a wiring error had routed the motor generator power to
the wall sockets in the computer room.

I told the customer that it was very good they had found this problem
before people used the sockets. If the cleaning lady had come in and
plugged a vacuum cleaner into the 400 Hz power, it would have probably
sucked all the air out of the room. :-)

-Rex, KK6MK


On Mon, 30 Aug 2004 23:42:03 -0700, Roy Lewallen wrote:

This comment reminded me of a High Current Horror Story related to me by
an older friend. In his youth he repaired radios, hi-fi systems, and the
like. One well-heeled customer had large, expensive speakers at the room
corners, with the hi-fi in the middle. He'd put the speaker wiring in
the walls. For connectors, he'd used ordinary mains AC power
receptacles, with matching cord and plug on each speaker.

When the repair was finished, my friend plugged the speaker back into
the outlet. He knew exactly what had happened the moment he plugged it
in when he heard a monstrous, deafening hum -- but even then it was too
late, the speaker was cooked. Let's see, 120^2 / 8(*) = . . . now,
that's LOUD!

Roy Lewallen, W7EL

(*) and I suspect that the speaker impedance was somewhat lower yet at
60 Hz.

Rex wrote:

On 30 Aug 2004 07:38:34 -0700, (Mike Monett) wrote:


High Voltage Sparks and Arcs - cursor down to "Crane Tangles with a 46 kV Feeder..."

http://205.243.100.155/frames/longarc.htm



Wow. Spectacular videos. I cranked up the sound for maximum effect on
the 500KV one, and after several plays, one of my destop speakers walked
off the desk and fell on the floor.

Our newer systems back in 1985 used dual MG setup 400 Hz and 50-60 VAC

anyway, one of the tape drive units had failed, IBM arrived and was checking
power connections in the power supply (they call it a power tub).
Other IBM guy (new young pup) kept leaning on the control unit while
the old timer IBM guy was trying to probe the voltages at the breakers.
Almost gave him a large shock before we told him to get off our control unit.

Same young pup wants to get under the floor to unplug the large
power connector russelstoll 30 amp 3 phase, old timer grabs him by
his belt from behind, and saved his life !

IBM guy takes the rubber cord and then gently glances the RS
connector to the floor supports (all metal and gounnded with copper cables)
large sparks when he did this !

Young ibm pup almost pee in his pants.

Turns out somebody on work crew did not wire the ground cables properly
so the floor was HOT HOT HOT ! Good thing it was carpeted flooring in the
computer center.

allen


Rex wrote:

And you reminded me of something too. Not really a problem, but could
have been.

When I was working on mainframe computers in the 70's we installed a new
machine in Europe. The power for the computer was supplied by a big
motor generator with an output of 3-phase 208 V 400 Hz (or was it CPS
back then?) power to the computer. I learned from the customer that they
discovered that a wiring error had routed the motor generator power to
the wall sockets in the computer room.

I told the customer that it was very good they had found this problem
before people used the sockets. If the cleaning lady had come in and
plugged a vacuum cleaner into the 400 Hz power, it would have probably
sucked all the air out of the room. :-)

-Rex, KK6MK