Re: Microwave oven capacitor.. Dead short overnight?

On Thu, 12 Jan 2006 18:57:37 GMT, "Rich256" <nospam@xxxxxxxxxx> wrote:

>
>"Jim Yanik" <jyanik@xxxxxxxxx> wrote in message
>news:Xns97496FBF3DBC4jyanikkuanet@xxxxxxxxxxxxxxxxx
>> maradcliff@xxxxxxxxxxxx wrote in
>> news:o56cs1lf6umfvrj2pvhkmnu06c3u6ird7h@xxxxxxx:
>>
>> > On 12 Jan 2006 01:49:06 GMT, Jim Yanik <jyanik@xxxxxxxxx> wrote:
>>
>> I once got across the sparkplug of the gas engine of my mini-bike;magneto-
>> generated,that's about 40KV,one heck of a pulse.I can guess what a TASER
>> shot feels like.
>
I bet that voltage made your voice go up a few octaves :)
I wonder why they have such a high voltage?
I may be wrong, but I think cars only have about 5KV to 10KV going to
sparkplugs.

>The megneto is a limited pulse. Doesn't quite approach what can be in a
>large capacitor. Both can hurt like hell.

Similar to an electric fence. They are basically a capacitor
discharge into a coil that puts out a pulse about the same as an
ignition coil.

>I got "bit" just turning the flywheel by hand on a mower engine. Checking
>how close the magnets came. The plug wire was close to my hand. Just made
>me jump a bit.
>
Thats good, then you knew the magneto was working. Thats how I always
test them. The shock is minimal when you turn by hand compared to
when the engine is running.

>I got my fingers across a 300 VDC source once. The current flowing from
>one finger to another. I had a hard time letting go. My army hurt for two
>weeks.
>

DC is much worse than AC. When I was a kid I had gotten an old tube
type army radio transmitter. I got about 1000VDC shock, in addition
to the RF coming from the unit. I was grounded to a metal microphone
in my other hand. The chair under me was a heavy oak chair. After
that jolt, I was sitting on the concrete floor about 20 feet away, the
chair was flipped over and 10 feet from my bench, and the microphone
was all the way across the basement, with the plug pulled out of it,
and it hit my friend as it flew. My friend said I was walking around
in a daze for at least a half hour, and I kept drinking water. He
said I was not making sense, but I did pull the plug on that
transmitter while stumbling around.
I vividly remember this happening, but I still to this day find this
void or memory loss for a short time. I think I darn near
electricuted myself that time. I know I touched a tuning capacitor
that was directly across the high voltage output of the power supply
with a huge electrolytic cap right ahead of it. I grabbed it bare
handed, and with that mic in my other hand, I got the full load.
Additionally, I did not have a decent load on the antenna (like I
should have), and got the full load of the RF too. This thing
transmitted in the AM band, and used to knock everyones AM radio
stations off the air. After several complaints from neighbors to my
parents, my father took that thing away from me. Probably the best
thing he ever did. Even though back then I was really mad at him.
The electronics devices in the 1950's and 60's were far more dangerous
than those made today. Today, most circuits are harmless, except for
capacitor discharges, and of course the 120VAC line cord.
.

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