Re: Modulation+Plasma Tubes(Was Stereo amplifier)

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Stephen Conner by way of Terry Fritz <teslalist-at-qwest-dot-net>" <steve-at-scopeboy-dot-com>

At 16:00 08/03/03 -0700, you wrote:
>As the audio frequency
>was swept from 20 Hz to 20KHz, the plasma in the tube went through dramatic
>changes in both color and appearance! There was a few audio frequencies that
>caused the plasma to break up into a series of beads! The RF frequency
>didn't seem to matter, it was actually the audio modulation that caused the
>changes!

As far as I know this is 'Acoustic Arc Resonance'. As the name suggests 
it's an acoustic standing wave set up inside the discharge tube by the 
audio modulation. I first read about it in a designer's manual for 
high-frequency lighting ballasts. I also saw it once when I was playing 
around with one of those electronic switching NSTs and an old piece of neon 
tubing. I don't know about the colour changes, though.

Steve C.