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Subject: Re: [motm] Lights

From: KA4HJH <ka4hjh@...>
Date: 2003-10-20

>From: Dave Halliday <dh@...>
>Cold cathode tubes use an inverter to generate the voltages needed. I would
>not want to have that sort of electrical noise near my system. They do look
>way cool but noise is not a good trade-off... Same deal with using a
>switching supply for power.
>
>--LH--
>I wondered if the inverter would create any appreciable noise if it is
>powered from an isolated source like a decent size 12VDC wall wart. I
>certrainly would not use up capacity on my linear synth power supply for
>that. The design I was contemplating would contain all the inverter widing
>inside copper pipe. I have a couple I bought to play with. I'll have to do
>some experimenting to see if I can detect any induced noise.

It's worse than a switching PS. At least the output of that is DC. The
output of the inverter is pulsed DC at a high frequency. It should radiate
RFI (with a boatload of harmonics) all over the place.

Putting it inside a pipe is a start but the wires leading up to the lamp
and the lamp itself will all radiate.

>Do you have any particular experience with them causing noise in audio gear?

This specifically, no. Put it near an amplifier with some gain like a preamp.

Who knows, you might get lucky. But it sounds like a bad idea to me.
--

Terry Bowman, KA4HJH
"The Mac Doctor"