[sdiy] Static Damage to ICs

[KA4HJH]

>>If I've read this somewhere else I wouldn't belive it.

I can't think of any other list where the off-topic stuff is as interesting
as on Synth-DIY.

>>What's the deal here? Is it the charachteristic of the tape
>>or is it charged during unrolling the tape?
>>
>>
>Apparently the charge is created by the unrolling of the tape, so it is caused
>by the material that the tape is made from as well as the unrolling/unsticking
>action.

Unrolling a piece of plastic tape works REALLY well for generating static
electricity! I notice this all the time when wrapping/opening packages.

This is why such a simple device as the van de Graaf generator--which
doesn't have anything touching the belt except the pulleys it's running
around--can create such high potentials. The electrode on top provides a
place for electrons to accumulate (imagine a capacitor with one plate and
the surrounding air as the dielectric). The charge is all on the outside of
the electrode--there's none on the inside because the electrons spread out
on the outer surface in their attempt to avoid each other. A sphere is the
most efficient shape since it can hold the maximum charge while having the
least corona discharge. Torroids also work well.

Then there's that electrostatic generator that works off of water dripping...


>I just rubbed my sleeve against my shirt and was easily able to peg the meter
>at well over 20KV!

I have an ancient 30kV electrostatic voltmeter that looks like something
out of the Frankenstein lab. It has a big insulated electrode sticking out
of it. I don't dare set it anywhere near the van de Graaf when it's running
for fear of frying it.


Needless to say none of this has much to do with building analog
synthesizers but what a great list.

Ozone smells much better than burnt epoxy and melted lacquer.
-- 

Terry Bowman, KA4HJH
"The Mac Doctor"

"It gets calls when nothing else works"--Walter Eugene Scott, PdD,
explaining somewhat facetiously why a "TV preacher" was smoking a cigar.