[Fwd: Re: biofeedback]/ theremin

[patchell]

    I would like to double this .......

    One of the big problem with anything that is powered off of your AC line is
leakage through the transformer.  I remember one place I worked sold a video
character generator to a hospital.  Even though nothing in this thing would be
connected to anybody, it still had to meet the leakage requirements.  I had to
order special transformers in order for them to buy the equipment.  I don't
remember what spec they had to meet (this was 20 or so years ago), but it wasn't
hard to find them....

    But still, the battery power thing is probably a good idea, and the thing
should be isolated if at all posible from your AC wiring.

Peter Blackett wrote:

> Hi,
> just one safety point .
> If your going to be experimenting with any direct electronic connections
> to your body then please either
> 1. use battery powere equipment with built in amplifiers [ so no mains
> connectors ].
> or
> 2 make sure that there is good isolation between the signal electrodes
> that connect to your body and the rest of the circuits.....
> I think you could use opto isolators or transformers to provide the
> isolation .
> But it might be possible to make a Theremin type device that would be
> safe and not too dificult to control .
> I think the changes in skin resistance / nerve signals are small
> compaired to the background noise , so some filtering would be needed .
> regards for the new year also ....
> Peter
> South London England
>
> -------- Original Message --------
> Subject: Re: biofeedback
> Date: Tue, 2 Jan 2001 20:06:49 +0100
> From: Torbjörn Hörnfeldt <torbjorn.hornfeldt at telia.com>
> To: <synth-diy at node12b53.a2000.nl>, "Dave Krooshof" <krooshof at xs4all.nl>
> References: <l03110706b676a77ebf23@[194.109.165.97]>
> <l03110706b676a77ebf23@[194.109.165.97]>
> <l0311070db676d554877b@[194.109.164.133]>
>
> Nice seeing Michel Waisvisz being mentioned on the list. After looking
> at
> the web-site I am a bit confused though. I remember the Cracklebox as
> having pots as well as touch surfaces. (This is from some issue of the
> STEIM
> publication which I subscribed to at the time.) Must have been something
> else though. Anyone who has a clue?
>
> Torbjörn
>
> ----- Original Message -----
> From: "Dave Krooshof" <krooshof at xs4all.nl>
> To: <synth-diy at node12b53.a2000.nl>
> Sent: Tuesday, January 02, 2001 2:05 AM
> Subject: Re: biofeedback
>
> <snip>
>
> > I am, however, very much interested in brain-electronics contact.
> > Now it's still one way for me, as in playing my open synths by toughing the
> > boards of the electronics. (http://www.xs4all.nl/~mwais got me into this)
> > If the resistance of the skin is this high, yet can do so much interesting
> > stuff, it must really interesting to use the muscle or even nerve
> > electronics, as that is more active control.
> > Touching electronics gives me the feeling I control the actual process,
> > rather then just triggering it. (compare bow vs. plucking strings). Pushing
> > the electronics by thought must be a fantastic experience.
> >
> >
> > Dave
> >
> >
> >
> >
> >
> >
> >
> > --------------------------------------------
> > Dave Krooshof http://www.xs4all.nl/~krooshof
> > geluidstechnicus @ http://www.ahk.nl/the/theatertechniek_ov.html
> > webmaster: http://www.popronde.nl
> >
> >

--
 -Jim
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