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From: minsky@media-lab.MEDIA.MIT.EDU (Marvin Minsky)
Newsgroups: sci.electronics
Subject: Re: Light-Dimmer Noise, was Re: Ferrite Beads
Message-ID: <4992@media-lab.MEDIA.MIT.EDU>
Date: 23 Jan 91 04:59:50 GMT
References: <1991Jan18.162458.29063@bronze.ucs.indiana.edu> <4931@media-lab.MEDIA.MIT.EDU> <1007@eplunix.UUCP>
Reply-To: minsky@media-lab.media.mit.edu (Marvin Minsky)
Organization: MIT Media Lab, Cambridge MA
Lines: 12

In article <1007@eplunix.UUCP> raoul@eplunix.UUCP (Nico Garcia) writes:
>In article <4931@media-lab.MEDIA.MIT.EDU>, minsky@media-lab.MEDIA.MIT.EDU (Marvin Minsky) writes:
>> Sorry about last message.  Does anyone know if ferrite beads can
>> reduce the RF noise from light-dimming devices?
>
>We avoided the whole issue and replaced the SCR light-dimmers with the
>bulky, hairy old linear light dimmers. They work great and don't make
>the occasional buzzing noise of the SCR's, which was a problem for our
>audio experiments.

How do the "linear" ones work?  A rheostat would be too hot, and a
variac too expensive (not really) -- and both are too large to fit in a
standard domestic switch-box.