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Static electricity detector for the blind?

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Brian Gaff

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Jul 1, 2019, 4:43:15 AM7/1/19
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Hi does anyone produce a probe that can detect rising electrostatic charge,
say on a person. I have a friend who you can hear crackle when they use my
vacuum cleaner. I do not have this trouble, but it occurred to me the only
way currently I know of is a gold leaf electroscope, though these days
tending to use aluminium coated plastic, which move apart as you bring the
electrode near a body which is charged up.
What I was looking for was the static equivalent of a metal detector, where
a rising tone can be heard as you bring the probe near a charged up item.
Anyone seen such a thing?
Not much good if it costs an arm and a leg though!

Brian

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J. P. Gilliver (John)

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Jul 1, 2019, 3:52:58 PM7/1/19
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In message <qfch32$dlu$1...@news.albasani.net>, Brian Gaff
<bri...@blueyonder.co.uk> writes:
>Hi does anyone produce a probe that can detect rising electrostatic charge,
>say on a person. I have a friend who you can hear crackle when they use my

Your friend is improperly earthed [smiley] ...

>vacuum cleaner. I do not have this trouble, but it occurred to me the only

More seriously: does your friend tend to wear clothing made from
man-made fibres more than you do? That could be an explanation. Do they
tend to get more of a charge walking across certain carpets than you do?
[]
> What I was looking for was the static equivalent of a metal detector, where
>a rising tone can be heard as you bring the probe near a charged up item.
> Anyone seen such a thing?

Sorry, not aware of anything. The input impedance of most multimeters
these days is probably sufficient that - especially with a series
resistor - they could yield something, but ...

> Not much good if it costs an arm and a leg though!

... the only talking one I've ever seen _was_ expensive.
>
>Brian
>
John
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Listen, three-eyes, don't you try to out-wierd me, I get stranger things than
you free with my breakfast cereal. (Zaphod Beeblebrox in the link episode)

Brian Gaff

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Jul 2, 2019, 2:40:43 AM7/2/19
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Yes tandy used to make a talking Multimeter based on an old Sharp chip.
I imagine its now very obsolete. They tended to brand stuff already out
there.
No way back in the 1970s, at TV factories they bought an eht probe, It
seemed to basically be some kind of inert plastic tube with a big metal bit
on the end and it ran on a pp3. Not much inside, just a single FET I think,
and a meter, plus a few bits and pieces.

Thus one might assume it would have been relatively simple to use the meter
output to change the frequency of an audio oscillator.
It actually could pick up voltages on stuff some feet away, and was
surprisingly immune to RF or magnetic field spurious signals on what must
have been a very high impedance probe.
You were right about clothing though. We used to try it on the office girls
as they walked through, very funny showing them how electrically 'hot' they
were. OK the hormones of youth!

These days though one does not need such things except perhaps when handling
mosfet based components not connected to anything, but I remember noting how
charged up a vinyl record could get by just sliding it out of its inner
sleeve. I often wonder why they did not press them out of the inert plastic
they made the probe shell out of, but maybe it was not suitable.

If I see the lady this week I'll ask her about the soles of her shoes though
since it seems that as I have carpets here which are mostly synthetic,
certain types of plastic soles can gather the free electrons needed to
charge put the person. However it is odd since the vacuum cleaner hose is
all made of plastic except the very end bit about 6 inches long, and one
would not expect such a small mass to be able to give the sound or the
shocks she generates.
I guess she could be an alien, but if so, I do not think the Earth has much
to worry about!

Brian

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J. P. Gilliver (John)

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Jul 3, 2019, 7:39:19 AM7/3/19
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In message <qfeu9a$p3o$1...@dont-email.me>, Brian Gaff
<bri...@blueyonder.co.uk> writes:
>Yes tandy used to make a talking Multimeter based on an old Sharp chip.
> I imagine its now very obsolete. They tended to brand stuff already out
>there.

I miss Tandy; though far from perfect, they were there. Maplin too.

> No way back in the 1970s, at TV factories they bought an eht probe, It
[]
>Thus one might assume it would have been relatively simple to use the meter
>output to change the frequency of an audio oscillator.

Indeed. Probably not done in the workplace as it'd be irritating to
sighted colleagues (and they might actually be able to make a health and
safety argument stick for saying the area/work was unsuitable for vis
folk).
[]
> You were right about clothing though. We used to try it on the office girls
>as they walked through, very funny showing them how electrically 'hot' they
>were. OK the hormones of youth!

[smiley]
>
>These days though one does not need such things except perhaps when handling
>mosfet based components not connected to anything, but I remember noting how

Wriststraps and the like have become the norm (for a decade or two) in
most electronic servicing now, or at least were at messybeast, perhaps
less so at BBA Reman.

>charged up a vinyl record could get by just sliding it out of its inner

Especially when the inner sleeve was polythene!

>sleeve. I often wonder why they did not press them out of the inert plastic
>they made the probe shell out of, but maybe it was not suitable.

More likely cost.
>
>If I see the lady this week I'll ask her about the soles of her shoes though
>since it seems that as I have carpets here which are mostly synthetic,
>certain types of plastic soles can gather the free electrons needed to
>charge put the person. However it is odd since the vacuum cleaner hose is
>all made of plastic except the very end bit about 6 inches long, and one
>would not expect such a small mass to be able to give the sound or the
>shocks she generates.

Vacuum cleaners generate charge more from the air rushing through, in a
way not a million miles from how a Van der Graaf generator or Wimshurst
machine works. Or so the manufacturers of the static-dissipative vacuums
sold for computer and electronic servicing would claim.

> I guess she could be an alien, but if so, I do not think the Earth has much
>to worry about!

I told you she wasn't earthed!
>
>Brian
>
John
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

The thing about smut is it harms no one and it's rarely cruel. Besides, it's a
gleeful rejection of the dreary and the "correct".
- Alison Graham, RT 2014/10/25-31

Brian Gaff

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Jul 7, 2019, 3:34:02 AM7/7/19
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Yes vacuums do generate static, but the fact that only one person gets the
shocks says to me its not that. In any case the Bosch and the Henry act the
same for her.

With regard to Maplin they must have been around late 70s, but only mail
order as the used to advertise in Practical Wireless.

In my day, health and safety was not an issue since it was the age when folk
were assumed to still possess common sense, ie keep one hand in your pocket
etc near high voltages.
I regularly got shocks from the mains but only on one hand. A curse here
and there was normal.

Brian
Brian

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