Re: Complete destruction if the Geeks perfectly good p133...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Mark Broker by way of Terry Fritz <twftesla-at-qwest-dot-net>" <broker-at-uwplatt.edu>

>Original poster: "Jason Petrou by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jasonp-at-btinternet-dot-com>
>
>Hi all (esp. chris)
>
>I had a look at the pics from the geek frying that poor old PC... I am very
>impressed, and I have a couple of questions, and a theory...

We were equally impressed, as well.  "Hit it again, it ain't dead yet!"

>Theory - why the motherboard didnt die when it was hit with arcs - the
>capacitance between the ceramic casing of the chip and the air, and the
>board and the air caused the skinn effect to take place, making the
>electricity shoot over the surface of the board/components to the grounded
>case, not damaging it. Dont ask me about the reeboot thou :)

Skin effect is only valid for good conductors.  Last time I checked, the
ceramic casing of a chip was not too conductive.

More likely reason was that the case was grounded.  The inside of the
plastic PC case was a sheet of aluminum.  A similar Faraday cage is around
most monitors (presumably the one we fried had it, and I know that the 20" 
HP I'm curerntly staring at has one...).  The PC didn't die until we
REMOVED the ground plug from the power cords.  After that it was all over.

The mouse and keyboard were atop the monitor during the beginning, and
recieved FREQUENT hits.  Neither were operable upont reboot.

>Question - What dod you plug the computer into? It seems pretty daft to plug
>it into the mains when you have a million volt arcs hitting the thing...

Standard $10 Walmart-type power strip and 50 foot extension cord into the
120 mains.  The video camera was also on the 120mains, presumably on a
different circuit, and there is noticable ghosting when the sparks were 
flying.

>Question 2 - I have a pretty pants computer and wouldnt mind one that could
>take million volt arcs  and still work - who was the computer made by? Just
>to show how well it must have been built...

We'll build you a good one!  :-)


>From this experiment, we feel that as long as a PC is well grounded, you
should be fine.  It helps if the coil is running on a completely different
circuit away from other wiring.  Our testing doesn't get much more extreme.....

Mark Broker
G-5 #10