vac tubes / was Re: Schematics of Atanasoff-Berry

[Pete Turnbull]

On 05/09/2008 14:37, dwight elvey wrote:
>> Date: Thu, 4 Sep 2008 11:59:04 -0400> From: wdonzelli at gmail.com> To: cctalk at classiccmp.org> Subject: Re: vac tubes / was Re: Schematics of Atanasoff-Berry> > > There is no green Ne-2. You can put a filter on a NE-2 and> > get a nice red or yellow but not green.> > Well, you are technically correct, as "NE-2" was originally a standard> - the little orange glowing tube we all know and love, but there were> some makers that did make a green version. The inside of the glass> bulb was frosted with a green phosphor.> > --> Will
> Hi
>  Yes, I've seen the phosphor ones but I think they may use
> a different mixture of gas.
>  Using a diffraction grating or prism on a neon shows one yellow
> and two red bands( as I recall ).
>  I suspect that the phosphor ones would have different
> operating voltages.

I don't think so, or at least not very different (I didn't actually 
measure it).  I've got a couple here, salvaged from flashguns that had 
one red/orange neon and one green one.  They look the same, except for 
the band of phosphor at one end of the green ones, and ran off the same 
voltage.  The green ones aren't completely covered with phosphor inside, 
and it's possible to see the usual orange glow when you look in the end 
with the wires, too.  I must go and find a diffraction grating -- I know 
I've got one here somewhere...

-- 
Pete						Peter Turnbull
						Network Manager
						University of York