[TCML] flourescent light trick

[Peter Terren]

I once had a modified neon tube with a filament. Because it couldn't be 
bombarded properly it was gassy but had beautifull striations the full 
length of the tube. I was in a hurry and couldn't photograph it immediately. 
When I returned in the morning it was largely gone to my regret.
There is structure in single sparks in air with frequent gaps in a 
proportion of single sparks which I have studied here:
http://tesladownunder.com/HighVoltage.htm#Spark%20structure
They occur towards the negative end within the last third of the total 
length. They affect up to 50% of impulsive single discharges and are mostly 
seen at lower intensities and are still present when simultaneously viewed 
in two directions with a mirror.
Peter

----- Original Message ----- 
From: "William Beaty" <billb at eskimo.com>
To: "Tesla Coil Mailing List" <tesla at pupman.com>
Sent: Sunday, November 18, 2007 4:06 PM
Subject: Re: [TCML] flourescent light trick


> On Wed, 14 Nov 2007, Chris Swinson wrote:
>
>> One thing I noticed with flu-tubes, that if you walk away from the coil
>> slowly, it goes dim, but just before it goes out totally the light
>> alternates inside the tube, such as 1" on, 1" off.. all the way up the
>> tube..
>
> That's called "positive column striations," and fluorescent tubes always
> have them all the time... but usually they're vibrating back and forth too
> fast to notice.   If you have a straight piece of clear neon sign tube,
> and sweep it rapidly back and forth while lit, then you can see the moving
> patterns.  They're also called "jellybeans" by neon sign makers.  With
> just the right gas mixture and high-freq power supply you can create
> stable ones in a neon sign, so the sign is made of "dotted lines."
>
> I wonder if sparks at one ATM also have them.   If the blotches are moving
> around fast, we might never realize that they exist.   (View sparks with a
> spinning mirror and look for swerving stripy patterns.)
>
>
>
>> always thought that was pretty neat! never understood why it would
>> light up alternate inches in the tube though!
>>
>> Chris
>
>
>
> (((((((((((((((((( ( (  (   (    (O)    )   )  ) ) )))))))))))))))))))
> William J. Beaty                            SCIENCE HOBBYIST website
> billb at amasci com                         http://amasci.com
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