[opendtv] Re: Europe now debates i vs p

Yes, the hotter it is, the more rapid the cooling rate. But, I recall
observing (personally) many years back that you could modulate an
incandescent bulb at audio (music) frequencies without raising the bulb
temperature to a visible glow. This then was broad spectrum infra-red
transmission.

Barry Wilkins =20

-----Original Message-----
From: Craig Birkmaier [mailto:craig@xxxxxxxxx]=20
Sent: Monday, 13 September 2004 11:55 p.m.
To: opendtv@xxxxxxxxxxxxx
Subject: [opendtv] Re: Europe now debates i vs p


At 8:58 AM +0200 9/13/04, jeroen.stessen@xxxxxxxxxxx wrote:
>I'd say that Doug is right. I remember long time ago a hobby
>project (in a magazine) where a lamp was used to carry speech
>over a distance, by modulating the filament current. While it
>may take a long time for a filament to cool off completely,
>initially the cooling goes very fast. It has to do with the
>radiated power being proportional to the FOURTH power of the
>temperature. Thin white hot metal will cool very quickly !

YUP.

We are talking about the ability to perceive the modulation in=20
intensity of the "flickering" light source.

Regards
Craig
=20
=20
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