Hello,

I have a coil made that consists of 240 feet of 20 AWG magnet wire. It is
actually 3 - 80 foot strands in parallel strands in the same coil to reduce
DC resistance of the coil. The coil is wound in a manner so as to provide
parallel wires laterally around the forehead, (9 rows of 3 parallel 20 AWG
wires and 4 layers thick). I am going to feed it with either one of two
methods.

One of them would be a higher frequency, say 50 - 100 Hz 30% duty cycle
square wave pulses with that pulse train to be switched on and off at the
frequency I am trying to induce (4 - 14 Hz) with that switching frequency
also at a 30% duty cycle. The exact frequency would depend upon the
inductive reactance of the output coil which I have yet to test to
ascertain.

The other method would be to simply feed the coil with a 30% duty cycle at
the fundamental frequency I trying to induce, 4 - 14 Hz). This would be
another possibility and more direct than trying to accomplish the
entertainment with a higher frequency pulse train modulated at the frequency
of entertainment I am trying to achieve.

I plan to use a signal generated by a computer parallel port to generate the
fundamental frequency, as I already have that signal to control a CES unit I
have created. I have that signal optoisolated and will use a set of
darlington transistors to actually drive the coil. The general scheme would
be the same as is commonly used to drive a relay coil from a parallel port
complete with a diode to protect the transistors when the field of the coil
is dropped and the field collapses.

I have two questions:

The first one is which of the two driving methods above do you think would
be most effective. By that I mean use the higher frequency pulse train
(50 - 100 Hz) modulated at the fundamental frequency I am trying to entrain
at or driving the coil directly at the fundamental frequency it's self.

The second question is do you think I should actually use 2 coils spaced a
small distance apart wired in reverse so as to create a field with one in a
north and the other in a south ward orientation. This would create a
difference field, one positive and one negative across the top of the
forehead. This might act somewhat like a figure eight coil creates, with a
north and south face applied to regions of the head, thus possibly inducing
a current directly under the axis of the differential fields.

Any feedback would be greatly appreciated. Oh yeah, also... Has anyone
here ever tried to create a rTMS with a retriggerable coil gun circuit? The
discharge of some big caps through a coil like they do in coil guns to sling
a magnet or nail must create one heck of a field. Winding a figure eight
coil should not be to difficult to use with such a circuit.

Please excuse the delay in my replying as I am working several hours from
home and long hours, therefore I will probably not see any reply for several
days after it is posted. I am however very interested in any replies or
responses I can get.

Thank you all for your time and help.

Mark (grgeek)
----- Original Message -----
From: "Mark Jones" <grgeek@...>
To: <mindexplorersw@yahoogroups.com>
Sent: Friday, August 06, 2004 12:38 AM
Subject: information request for anyone out there


> Hello,
>
> I have an experiment I am involved in. I am looking for some advice. I
> have built a headset that has sound (for binaural beats) and photonic
> stimulation incorporated into it. I also have a CES device that I created
> that is controlled from the same circuitry for CES device. I use it to
aid
> in the induction of hypnosis. It is actually fairly effective.
>
> I am seeking now to add electromagnetic brainwave entertainment to it. I
> will add a large (long, but narrow) coil to the headset. My question is
> what do you think the most effective waveforms to feed the coil with would
> be? Would it be sinewave? Pulsed? Positive or negative spikes? What
> about pulse widths? Any ideas about if it would be logical to use a
series
> of short pulses at a high frequency gated to the actual frequency I am
> trying to achieve (say between 14 - 5 Hz)?
>
> I have looked at the Shakti Lite, but the goals are different there. I am
> seeking to entrain brain waves. Any information or references would be
> greatly appreciated.
>
> Thank you much.
>
> Mark (grgeek)
>