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VLF HV

  • Thread starter Dirk Bruere at Neopax
  • Start date
D

Dirk Bruere at Neopax

Jan 1, 1970
0
Another tricky problem in brain electrocution:)

I want to do some experiments on the effects of HV VLF electric fields on the
brain. The frequencies involved are 4Hz upwards and I'd like to use a sine
rather than spike waveform. Voltages to be approx 3000V/m upwards (values found
during thunderstorms).

The tentative setup would be to feed the AC signal to two large insulated
conductive plates, probably around 500mm x 500mm with a separation of at least
300mm, probably quite a bit more. The head would placed between them.

Now, transformers are not esp efficient at 4Hz, but then again I do not need to
drive much current (I think). Can anyone suggest what the transformer would look
like eg turns, core etc? Suggestions for driving circuit also welcome.


--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org
 
T

Tim Wescott

Jan 1, 1970
0
Dirk said:
Another tricky problem in brain electrocution:)

I want to do some experiments on the effects of HV VLF electric fields
on the brain. The frequencies involved are 4Hz upwards and I'd like to
use a sine rather than spike waveform. Voltages to be approx 3000V/m
upwards (values found during thunderstorms).

The tentative setup would be to feed the AC signal to two large
insulated conductive plates, probably around 500mm x 500mm with a
separation of at least 300mm, probably quite a bit more. The head would
placed between them.

Now, transformers are not esp efficient at 4Hz, but then again I do not
need to drive much current (I think). Can anyone suggest what the
transformer would look like eg turns, core etc? Suggestions for driving
circuit also welcome.
Not _my_ head!

At that low of frequency, and at the (implied) low current I would be
thinking of driving the plates with active devices. I suspect that
there are IGBT's that will do the job, and if not I have some VT-4C's in
my attic that should be able to stand 3kV on their plates.

Please note that I will have _nothing_ to do with this if you kill
somebody. Safety is your responsibility, not mine. If you sue me do it
in Kansas*. All of the safety measures that are implied by sticking
someone's head between a couple of plates carrying 1kV between them
should be observed (or even sticking a dog's or sheep's head in there
whilst and at the same time holding onto the animal). In fact, find a
few extra safety measures and stick to them, too.

- - - -

* My sister lived there for a while. While many of their cultural norms
make this agnostic, non-conformist west-coaster gag they do have the
refreshing opinion that if you do something stupid with someone else's
property it's your mistake to pay for, not McDonald's or my insurance
company.
 
D

Dirk Bruere at Neopax

Jan 1, 1970
0
Tim said:
Not _my_ head!

At that low of frequency, and at the (implied) low current I would be
thinking of driving the plates with active devices. I suspect that
there are IGBT's that will do the job, and if not I have some VT-4C's in
my attic that should be able to stand 3kV on their plates.

Please note that I will have _nothing_ to do with this if you kill
somebody. Safety is your responsibility, not mine. If you sue me do it
in Kansas*. All of the safety measures that are implied by sticking
someone's head between a couple of plates carrying 1kV between them
should be observed (or even sticking a dog's or sheep's head in there
whilst and at the same time holding onto the animal). In fact, find a
few extra safety measures and stick to them, too.
Well, I want sub mA current flow on short circuit, so it shouldn't be too
dangerous. I suspect your method might lead to instant lobotomy at best in case
of accident.

I suppose I'll have to work out the ballpark capacitance and stuff...

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org
 
A

Adrian Tuddenham

Jan 1, 1970
0
Dirk Bruere at Neopax said:
Another tricky problem in brain electrocution:)

I want to do some experiments on the effects of HV VLF electric fields on the
brain. The frequencies involved are 4Hz upwards and I'd like to use a sine
rather than spike waveform. Voltages to be approx 3000V/m upwards
(values found during thunderstorms).

How do you propose exposing the brain to the electrostatic field? The
skull and tissues of the scalp will be a pretty good electrostatic
screen at those frequencies.
 
T

Tim Wescott

Jan 1, 1970
0
Dirk said:
Well, I want sub mA current flow on short circuit, so it shouldn't be
too dangerous. I suspect your method might lead to instant lobotomy at
best in case of accident.

I suppose I'll have to work out the ballpark capacitance and stuff...
Resistor-coupled amplifiers, with high resistance will give you
automatic current limiting:


3kV
+
|
|
.-.
| | R = BIG
| |
'-'
|
o----------
|
|/
------------| (or some other amplifying device)
|>
|
|
===
GND
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

But I'd be concerned about capacitances, also.
 
D

Dirk Bruere at Neopax

Jan 1, 1970
0
Adrian said:
How do you propose exposing the brain to the electrostatic field? The
skull and tissues of the scalp will be a pretty good electrostatic
screen at those frequencies.

Probably.
However, they will not be perfect.
I'm interested because I have not seen anything documented on the effects of HV
fields, or lack of effects.

I assume that there will still be a polarising effect that extends through the
head. Apparently even a few hundred mV applied directly can cause quite
noticeable effects.

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org
 
F

Fred Bartoli

Jan 1, 1970
0
Dirk Bruere at Neopax said:
Probably.
However, they will not be perfect.
I'm interested because I have not seen anything documented on the effects of HV
fields, or lack of effects.

I assume that there will still be a polarising effect that extends through the
head. Apparently even a few hundred mV applied directly can cause quite
noticeable effects.

There can't be E field inside a conductor. Well at low frequency, and 4Hz
is... low.
 
D

Dirk Bruere at Neopax

Jan 1, 1970
0
Fred said:
on the


of HV



There can't be E field inside a conductor. Well at low frequency, and 4Hz
is... low.

Depends how good the conductor is.
Anyone tried it?
I would also have thought that it might induce current flow by capacitative
coupling.

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org
 
F

Fred Bartoli

Jan 1, 1970
0
Dirk Bruere at Neopax said:
Depends how good the conductor is.
Anyone tried it?
I would also have thought that it might induce current flow by capacitative
coupling.

Get some sense of reality:

How much is the intrinsic capacitance of 0.2m diameter sphere?
How much is the resistivity of human tissues.
Evaluate the time constant.
Then you can have an idea of the voltage gradient wrt to your frequency.

But I know in my bones, err... preferably in yours, that it'll be almost
nothing.

But then, if you do want to induce some real E field, why don't you put the
electrodes directly in contact?

I guess Joerg can give you some advice on building a debrainillator...
 
D

Dirk Bruere at Neopax

Jan 1, 1970
0
Fred said:
Get some sense of reality:

How much is the intrinsic capacitance of 0.2m diameter sphere?
How much is the resistivity of human tissues.
Evaluate the time constant.
Then you can have an idea of the voltage gradient wrt to your frequency.

But I know in my bones, err... preferably in yours, that it'll be almost
nothing.

Well, as part of the expt I will also be trying VLF modulation of kHz fields.
But then, if you do want to induce some real E field, why don't you put the
electrodes directly in contact?

Because I know about that technology already.
Armchair theorists say all kinds of things are not possible, until some
experiment shows they are. Then it's a case of "...of course it will work if XXX
is taken into account". An ounce of experiment is worth a tonne of theory.
I guess Joerg can give you some advice on building a debrainillator...

google, electrosleep
http://www.google.co.uk/search?hl=en&q=electrosleep&btnG=Google+Search&meta=
12000 hits

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org
 
W

Winfield Hill

Jan 1, 1970
0
Dirk Bruere at Neopax wrote...
Well, I want sub mA current flow on short circuit, so it shouldn't be
too dangerous. I suspect your method might lead to instant lobotomy at
best in case of accident.

I suppose I'll have to work out the ballpark capacitance and stuff...

If you don't think it's too dangerous, that's a very bad sign.

You mention 3kV/m with 0.3m plate spacings, which works out to 900V.
My latest HV amplifier design does +/-1200V, which would meet those
specs, but I think I'll not give you the details! Ahem. Here's a
+/-4kV amplifier on eBay ... However I recommend against it in your
case, http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7545103067
 
D

Dirk Bruere at Neopax

Jan 1, 1970
0
Winfield said:
Dirk Bruere at Neopax wrote...



If you don't think it's too dangerous, that's a very bad sign.

You mention 3kV/m with 0.3m plate spacings, which works out to 900V.
My latest HV amplifier design does +/-1200V, which would meet those
specs, but I think I'll not give you the details! Ahem. Here's a
+/-4kV amplifier on eBay ... However I recommend against it in your
case, http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7545103067

Well, we have Fred saying how there will be no effect whatsoever, and you
implying that it's a suicide machine.
Care to elaborate? Bear in mind that electrosleep machines have a very long and
safe history when it comes to actually passing sub mA current through the head.

You think the electric field alone will be more dangerous?

And I *do* know how to build amplifiers that will pump out kV and kW - it's just
that I don't actually want high power and complexity. Hence the transformer
question.

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org
 
W

Winfield Hill

Jan 1, 1970
0
Dirk Bruere at Neopax wrote...
Well, we have Fred saying how there will be no effect whatsoever,
and you implying that it's a suicide machine. Care to elaborate?

If the electrodes are exposed, they're dangerous to the touch.
You don't believe that? If the electrodes aren't exposed, on
account of insulation, most of the electric field ends up being
developed across the insulator, and not across the conducting
subject matter, the head and brain.

If you want to induce 500uA electrosleep currents in the head,
use electrodes: "The electrodes may be saline-gauze sponges over
metal plates applied between frontal and occipital locations."

There's also the electrosleep band. "Musically electrosleep assault
and dazzle the listener with dueling guitars, cascading keyboards
and manic vocals." No electrodes needed... Here's a sample:
http://stickfiguredistro.com/stickfigurerecords/stick016cd.mp3

Also, I found this: "I would advise against making your own machine
unless you are a very good electrical engineer with a good bio-medical
background. Good luck in finding a doctor who won't laugh his narrow-
minded, prejudiced, priest-like ass off when you mention this."
 
D

Dirk Bruere at Neopax

Jan 1, 1970
0
Winfield said:
Dirk Bruere at Neopax wrote...



If the electrodes are exposed, they're dangerous to the touch.

Not if they are powered at 900V with a short circuit current not exceeding 1mA
That's why I don't think your amp is of much use to me.
And it is why I asked a question about transformers at VLF. Certainly not
efficient, but I don't want efficiency. The voltage is only going to insulated
electrodes with a capacitance in the pF so the current should be negligible at
sub 10Hz frequencies.
You don't believe that? If the electrodes aren't exposed, on
account of insulation, most of the electric field ends up being
developed across the insulator, and not across the conducting
subject matter, the head and brain.

Probably.
And it will *probably* have no effect, but it's worth trying as part of the
expt. The other part of the expt involves modulating a kHz kV waveform with VLF.
If you want to induce 500uA electrosleep currents in the head,
use electrodes: "The electrodes may be saline-gauze sponges over
metal plates applied between frontal and occipital locations."

No, been there, done that.
There's also the electrosleep band. "Musically electrosleep assault
and dazzle the listener with dueling guitars, cascading keyboards
and manic vocals." No electrodes needed... Here's a sample:
http://stickfiguredistro.com/stickfigurerecords/stick016cd.mp3

Also, I found this: "I would advise against making your own machine
unless you are a very good electrical engineer with a good bio-medical
background. Good luck in finding a doctor who won't laugh his narrow-
minded, prejudiced, priest-like ass off when you mention this."

Actually, I do have a doctor friend who doesn't laugh at such things.
However, this has nothing whatsoever to do with medicine.


--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org
 
R

Rich the Newsgroup Wacko

Jan 1, 1970
0
Another tricky problem in brain electrocution:)

I want to do some experiments on the effects of HV VLF electric fields on the
brain. The frequencies involved are 4Hz upwards and I'd like to use a sine
rather than spike waveform. Voltages to be approx 3000V/m upwards (values found
during thunderstorms).

The tentative setup would be to feed the AC signal to two large insulated
conductive plates, probably around 500mm x 500mm with a separation of at least
300mm, probably quite a bit more. The head would placed between them.

Now, transformers are not esp efficient at 4Hz, but then again I do not need to
drive much current (I think). Can anyone suggest what the transformer would look
like eg turns, core etc? Suggestions for driving circuit also welcome.

Maybe start with something like one of these:
http://www.jcau.com/energymedicine/products/p7.html

Good Luck!
Rich

(Of course, if you really want to trigger a person's brain into action,
just find their hotbuttons and prod them until you piss them off. >:-> )
 
R

Rich Grise

Jan 1, 1970
0
Not if they are powered at 900V with a short circuit current not exceeding 1mA
That's why I don't think your amp is of much use to me.
And it is why I asked a question about transformers at VLF. Certainly not
efficient, but I don't want efficiency. The voltage is only going to insulated
electrodes with a capacitance in the pF so the current should be negligible at
sub 10Hz frequencies.

Well, I got a very respectable jolt once from a car coil that I had hooked
to a toy train transformer: 19 VAC, 60 HZ to the primary, and making fun
arcs with what came from the secondary, until I got my thumbs on opposite
terminals. BZZZZAAAAAAAT!!!

Of course, that had nothing to do with my current mental condition, nope,
no brain damage at all, not a bit, nope, nope, nope, nope.....

;-P
Rich
 
R

Rich Grise

Jan 1, 1970
0
There can't be E field inside a conductor. Well at low frequency, and
4Hz is... low.

FOUR HERTZ!!?!?!? I first read Dirk's post as "4 KHz".

Heck, just get a big rubber balloon, rub it in your hair, and wave
it around!

Good Luck!
Rich
 
C

Chris Jones

Jan 1, 1970
0
Winfield said:
Dirk Bruere at Neopax wrote...

If the electrodes are exposed, they're dangerous to the touch.
You don't believe that? If the electrodes aren't exposed, on
account of insulation, most of the electric field ends up being
developed across the insulator, and not across the conducting
subject matter, the head and brain.

If you want to induce 500uA electrosleep currents in the head,
use electrodes: "The electrodes may be saline-gauze sponges over
metal plates applied between frontal and occipital locations."

There's also the electrosleep band. "Musically electrosleep assault
and dazzle the listener with dueling guitars, cascading keyboards
and manic vocals." No electrodes needed... Here's a sample:
http://stickfiguredistro.com/stickfigurerecords/stick016cd.mp3

Also, I found this: "I would advise against making your own machine
unless you are a very good electrical engineer with a good bio-medical
background. Good luck in finding a doctor who won't laugh his narrow-
minded, prejudiced, priest-like ass off when you mention this."
If he is actually wanting the high electric field inside his flesh, then
obviously there will be a problem. Providing he is investigating the
effect of the head being placed in a volume of air which has an electric
field in it, then he should be fine. I think it would be possible (but
tedious) to do this in a way that meets all appliance safety regulations.
(e.g. TV sets can cause high electric fields in front of the glass.) I
thing that if the plates are insulated behind 6mm of polypropylene (or
whatever thickness one is legally supposed to use for the voltage in
question), then the electric field in the gap between the plates will
hardly be affected by the insulation, (at least for AC fields). Since the
dielectric constant of the insulating sheets will be greater than that of
air, the insulating sheets will drop less AC voltage than the same
thickness of air would.

Actually this idea of applying high voltage AC fields to the head sounds a
bit like the electrostatic headphones I built, adapted from from some in a
'70s Wireless World magazine. I think I had about 500Vp-p (1kVp-p
differential) of audio on each set of perforated plates (which were just
100mm square plates of single sided FR4 with lots of 3mm holes, and etched
sections around the edge), with a piece of kitchen cling-film stretched
over spacers in between the plates, the cling-film was charged to about 1kV
DC, through a resistor of a few tens of Megs made out of many resistors in
series so that several could fail quite safely. I connected several high
voltage ceramic capacitors in series with each amplifier output (each one
rated for more than the supply voltage), with a DC bias resistor from the
headphone connector to ground. The amplifier output stages were common
emitter with resistive loads so the resistors would stop it from killing me
anyway even if all of the many series connected caps were to fail. The AC
signal current from the amplifier was not dangerous, it just tickled if you
touched it, since it could only provide enough current to drive the couple
of hundred pF of the headphones.

The headphones sounded really good. With the voltage of my amplifier they
weren't quite loud enough, and had a tendency to collect dust inside, so
they needed frequent disassembly and cleaning.

Chris
 
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