Re: Electronic damage

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

Original poster: "Jolyon Vater Cox by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>

Speaking from personal experience of temporary "damage" or interference to
electronic systems from a Tesla coil , I can confirm of several instances
when my 3"
mini-coil has reset the time/date settings on my digital watch to "Sunday
1st January
1996"; on all occasions the watch was successfully adjusted to the correct
time/date
afterwards. Moral: keep digital/quartz watches away from the immediate
vicinity of a
operating Tesla coil. I think there more likelyhood for trouble with watches
with
plastic cases as these provide little shielding from the high voltage
electrostatic field
whereas a metal-cased watch would more likely be protected by the Faraday
cage
effect.

The RF field affects the working of a Kodak digital camera so it is
difficult to get
close-up pictures with the coil running. The field is so strong that the CFL
energy-saving lamp in my room flashes dimly in sympathy with the spark-gap
despite the fact that the lamp is 50" away and my TC is low powered (driven
by
ignition coil from low-voltage DC supply) with a 6" max spark
capability -good
evidence that the high voltage field extends a fair way from even a
modestly-sized
Tesla coil; with a big coil it is likely to be even worse.

Damage-wise, I understand CMOS chips (used in most computers, digital
cameras
and other electronic systems today) are more sensitive to electrostatic
discharge that
other technology although this may be less may be less of a problem when
they are
connected into a circuit as conductors and associated components prevent
tend to high
voltages from developing across the pins; electromagnetic induction in the
wires
might be a problem however. Needless to say, it is a good idea to keep
unconnected
CMOS chips well away from the high voltage field of a TC -or at least keep
the pins
shorted with conductive foam or aluminium foil to prevent damage.


Jolyon
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, June 18, 2002 8:14 PM
Subject: RE: Electronic damage


> Original poster: "Vanderputten, Gary by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <gvp-at-pvaintl-dot-com>
>
> I have used coils in theatre environments. With only a 1k w unit with a
15"
> secondary:
>
> * Fried my new $200 fluke taking a current measurement  - older models
were
> unaffected - Fluke was very nice about it.
> * Froze the digital theatrical lighting dimmer control board at twenty
feet,
> no permanent damage but had to faraday  the front of the tech booth  with
> chicken wire.
> * Used a digital camera and a camcorder at 3 feet with no ill-effect
> * Froze my computer at 10 feet - totally stupid of me - when I testing the
> tank circuit in the next room - no permanent damage.
> * Cell phones were noisy but otherwise unaffected.
>
> I recommend the obvious-
> * Establish good RF ground
> * Isolate your equipment mains as much as possible from other equipment.
> * Use EMI devices on all of your equipment
> * Faraday screen between important electronics and coil - this worked very
> well for me.
>
> Gary
>
>
>
>  -----Original Message-----
> From: Tesla list [mailto:tesla-at-pupman-dot-com]
> Sent: Tuesday, June 18, 2002 9:35 AM
> To: tesla-at-pupman-dot-com
> Subject: Electronic damage
>
> Original poster: "Anthony by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <firework-at-firework.co.nz>
>
> Hi there,
>
> I am new on the list. Years ago when I worked in a University Physics
> Department building lecture demonstrations I built a 2 metre high Tesla
> powered with three neon sign transformers in parallel.
>
> It worked very well and we just charged in to the lecture theatre and used
> it with no thoughts of all the electronics just through the wall in the
> back room. It would dimly light dimly all the fluorescent in a room
seating
> 350 students when we ran it. They had thyratron dimmers.
>
> We never had any damage problems. But  recently I was asked to run and
> event where a touring artist with his Tesla coil is going to figure on
> stage indoors.
>
> I am very leery of it but am I being too conservative?  Todays electronics
> items are I think vastly less forgiving than those of 25 years ago.
>
> We are also to supply pyrotechnic effects and they will be foil wrapped in
> locked metal trunks  well  away till he is done.
>
> But has any one had a computer blown?  I realise that in a small garage
> damage is easily done, but has any one ever run a coil on stage in a
> theatre with all the lights and sound gear up and running?
>
> Any one fried all the nearby cell phones or killed a walkman or blitzed
the
> lighting dimmers on the wall?
>
> I see how damage is possible but does it occur easily in practice?
>
> Interested to hear of your actual experiences in the matter as I am so out
> of touch now.
>
>
> Kind Regards     Anthony Lealand             Firework Professionals
> Ltd          Web   www.firework.co.nz
>
>
>
>
>