ORIGINAL MESSAGE:
On Sun, 24 Sep 2006 12:05:38 -0000, "pentalab" <jim.thomson@...>
wrote:
### Are u talking about 3-500Z's and 4-1000's ???? [glass
tubes] I have had new 4-1000's that glowed blue. It was
not gas either.... it was an anomoly/defect in the glass....per
Eimac. The glass would glow blue.... only when drive applied.
------------ REPLY FOLLOWS ------------
I don't think this is a defect. Many tubes show a fluorescence on the
inside of the glass when operating. I was told it was "soft" x-rays
caused by electrons impacting the anode and then striking the glass.
Whether that is the real cause or not, I've seen it many times.
Nothing to worry about.
The tubes that do not fluoresce probably have a different mix of
compounds or elements in the glass.
This should not be confused with a blue glow between the elements.
That is gas and is something to worry about.
Bill, W6WRT
