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Re: NEON- more pinhole suckins...

Dear John, 
thanks for your detailed description.

are there some of the 30 units which are dead on the transformer, but not 
punctured so the vacuum is lost? If so, try to fire them with your bomber.
If a discharge occurs when flashing your bomber, pressure is too low.
At those low pressures, electrons emitted go straigt from the the trode
and hit all in their way. when used with a 15kV transfo, the amount
of "cathode rays" will give enough energy to melt the glass at that point.

It reminds me to some Crookes tubes with small metallic parts inside 
filled with nitrogen at 1e-2 mbar, and powered by a large inductor,
will give a white heat (and melt) the metal within a few seconds 
STRAIGHT from the cathode. 

These tubes might not have been processed properly, so either there was 
to low pressure filled, or there were impurities remaining, which started to 
sputter the trode and getter the rare gas. 
If you're below 2mbar, it's just a question of hours till your cathode rays
will destroy the glass. (Be also aware of X-rays....)

Marcus

BTW: Thanks for your description of TEXAS business ethics, thinking about
practicing in the old world keeps me smiling. 


> 
> I've just gotten an entire load (approx 30 units) of clear-red repairs.
> About 80% of them have the proverbial "pinhole suckin" we talked about
> earlier.  This is a hole in the double back right where the electrode
> aims:
> 
>               -----  <-------- here
>              |  _  |
>              | | | |
>              | | | |
>              | | | |
>              | |  -
>              | |
>              | |
>              | |
> 
> On every one:  the suck in is indeed right where a bullet would land if
> fired from the trode shell.
> 
> All are 15mm clear red.  Most around 5-7 feet.  I didn't make any of
> these, but they appear to be not that old (they're Eurocom 'trodes,
> glass is still clear and fresh, boots still intact, etc).
> 
> There is more sputtering than I would expect for tubes of this age, so I
> am assuming that the fill may have been too low.
> 
> What I'd always assumed from seeing these before is that the 'trode
> arced thru to the metal letter, or a piece of GTO.  After discussing
> this on the list several months ago, examining these units (and talking
> to the installers), I agree this is NOT what's happening.
> 
> Anyway, I'm really interested in the electron bombardment theory (or is
> it a known fact?)  Why would electrons emit in such a narrow, focused
> beam? George Doll mentioned that Al Sklar wrote an article on pinhole
> suckins - does anyone know where I can find a copy?
> 
>     -John
>
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