The Fountain of Discordia
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How would I go about building a simple circuit that...
Hi, me and a friend are interested in the idea of Brainwave Entrainment, but not in the weaker, light and sound based forums of it. Therefore, we
wanted to build a magnetic helmet. Now, before going "Oh god, another newage fool." Just know that this type of device is used in clinical serttings
to help treat suicidal depression and other conditions, to great sucess. So, the basic problem is I'm not quite sure how to build a circuit that would
let me modulate the frequency of the magnetic pulses. Would anybody be willing to help me out?
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woelen
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You can use a voltage controlled oscillator for modulating the frequency of the signal. Simply apply a variable voltage on one of the pins of this
circuit and you have your variable frequency signal.
http://www.alldatasheet.com/datasheet-pdf/pdf/8985/NSC/LM566...
This is a single integrated circuit, you need to provide things like power supply and of course you also need to supply an external voltage, which
does the modulation.
The output of this little chip must of course be amplified, such that it can drive an electromagnet for generating a magnetic field.
From a non-technical view: Are you attempting to do this on yourself or your friend? Making a variable magnetic field can be a fun project on its own,
but experimenting with this on your own body does not seem like a wise thing to me. But that's just my opinion, it is your body and your
responsibility.
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not_important
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That application requires fairly good control of frequency, 0,1 Hz as a minimum for frequencies in the 3 to 20 Hz range, several experiments reported
values to 1/100 Hz. A simple oscillator may not be precise, accurate, or stable enough to be useful.
The waveform can be important, most studies used sine waves. Pulses or square waves are going to produce harmonics all over the place, from some
reports a rather undesirable condition.
Control of field strength is also needed, I assume you have means to measure it? Or maybe not seeing as you are asking about a rather basic technique.
I'd go for direct digital synthesis with the result driving a 8 to 12 bit DAC, or mixing two sine waves in the audio range and low pass filtering the
result.
Actually applying such fields to a subject means having good control of the signals, not using some cobbled together kludge of dubious quality. Stick
to the audio based forms until you've learned enough electronics that you don't need to ask how to build such devices.
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chemrox
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I've heard rumors of such devices being used to treat addictions eliminating abstinence syndromes for tobacco, alcohol and heroin. I cannot find any
papers and am reminded of the inventor that discovers a pellet made of cheap common ingredients that when added to water makes a fuel that competes
with gasoline. The story goes the inventor is killed or retired to the So Pacific...A more modest clinical accomplishment might be more impressive.
I'd be interested in reading if you have some refs.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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Mr. Wizard
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I t would also be possible to use the output of a computer's sound card to obtain almost any sound-wave or combination thereof. I'm sure there are
free-ware sound generation applications available, and the electronics is sitting in front of you. Even an old 'junk' PC could serve as a source of
sound to feed an audio amplifier. The audio amplifier is made to supply current to make electromagnetic pulses. You will have to match the 'impedance'
of the coil to the 4, 8, or 16 ohm amplifier.
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Vogelzang
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In the book Psychedelic baby reaches puberty by Peter G. Stafford they discuss the hallucitron, a device that alternately flashes lights on closed
eyes to produce various illusions.
http://www.google.com/search?hl=en&client=firefox-a&...
[Edited on 28-5-2009 by Vogelzang]
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chemoleo
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I think this is what he refers to:
http://en.wikipedia.org/wiki/God_helmet
May you find thy spirit with electromagnetic fields!
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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Vogelzang
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Maybe it can facilitate out of the body experiences.
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hissingnoise
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Or, failing that---out of the head experiences. . .
People having multiple mini-strokes have reported having being overcome by pleasant feelings of great anticipation just before the onset of a stroke.
This is thought to relate to electrical/magnetic disturbances which appear to be connected to the build-up to strokes.
As for the GodHelmet, it isn't something I'd want anywhere near my remaining quota of brain cells---and I would have credited Dawkins with the
intelligence to avoid such contraptions, but perhaps he simply wanted to display total fearlessness. . .
When I feel in need of an expansion of consciousness, a few tokes of cerebral ganja suffices!
[Edited on 29-5-2009 by hissingnoise]
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not_important
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A better Wiki link would have been http://en.wikipedia.org/wiki/Transcranial_magnetic_stimulati...
This is somewhat different than the earlier sinewave stimulation research. TMS uses short pulses of current to drive electromagnets generating fields
of 1 to 4 Tesla, using particular patterns that are more easily produced using a computer rather than from simple circuit. The coil shape is somewhat
important, as are its electrical characteristics as the pulses have short (~100 usec) rise times.
Indeed, there are commercial products meant to be used with PC sound cards, and coming with the software to produce the desired patterns. One such
product, which by no means am I endorsing, is
http://www.shaktitechnology.com/winshakti/rotating/index.htm
Or you could take a different route, as per Sasha
| Quote: | My response to him was to ask him three questions. One: Was he familiar with the psychedelic experience? "Yes," he said. Two: Would he trust me as a
guide in such an experience? He looked at me strangely for a moment, and then said, "Yes, of course." Three: Would you come down the hall with me to
the chemistry lab and trust me if I would try a quick experiment? "Sure," he said. So we went down to the lab where there was a giant dry-ice
container, and I opened it up, and asked him to put his head inside this container and to breath twice, deeply, through his mouth. He did this, and I
caught him as he stumbled backwards. "Wow," he said. "That was a totally unexpected turn-on." "Did it remind you of LSD?" "Yes," he said. "Initially I
went out there quite far, but you were there and I had no problem re-centering myself."
We returned to the office. I asked him, "Do you think you could separate the mechanisms of action of LSD on you, as distinct from the actions of
carbon dioxide?" He told me quite honestly, "No, they sure came on in the same way." So, I asked him, could you possibly design a research project
that would result in an explanation of the difference of the action of LSD and of carbon dioxide? He shook his head. He admitted that it might be very
difficult to explain the action of LSD (which has some 49 atoms in its structure) if he couldn't explain the action of carbon dioxide, which contains
only 3 atoms. |
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hissingnoise
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Let's all get...er...asphixiated. . .
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