[sdiy] Theremin

[James Patchell]

These things use an interferometer....something I am pretty familiar 
with....they are generally, tempremental.

At 09:09 PM 7/6/2004 +0200, Roman wrote:
>proffesional laser distance meters used by construction workers measure
>from 30cm up to 30m with 1mm resolution, or was it 1cm, can't remember.
>I played with it in shop. Big device as for handheld unit, and kinda
>expensive.
>This 30cm short limit is determined mostly by the instrument size -
>measurement
>counts from its back end, so it's possible to measure about 10cm of light
>travel
>with something that is made in thousands and sold to civilians.
>
>Roman
>
>----- Original Message -----
>From: "Scott Gravenhorst" <music.maker at gte.net>
>To: <synth-diy at dropmix.xs4all.nl>
>Sent: Tuesday, July 06, 2004 3:09 PM
>Subject: Re: [sdiy] Theremin
>
>
> > Reflected brightness is measured.
> >
> > I think the round trip time is a bit quick for simple analog circuits or
> > even digital to measure.
> >
> > "Paul Maddox" <P.Maddox at signal.qinetiq.com> wrote:
> > >Richard,
> > >
> > >> 'Scuse my dimness, but do you measure distance by calculating reflected
> > >> trip time, or reflected brightness?
> > >
> > >good question!
> > >
> > >> Yeah, but you don't get that cool 50s retro antenna look. ;-)
> > >
> > >50's?
> > >Man, you're to far ahead, try the 20's....
> > >
> > >Paul
> > >
> >
> > ---------------------------------------------------------
> > - Where merit is not rewarded, excellence fades.
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> > -- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
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> >

         -Jim
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