From: Robert Baer
X-Mailer: Mozilla 4.75 [en] (Win98; U)
Subject: Re: Home brew linear accelerator?
References: <3D8B60B3.1090107@BOGUS.earthlink.net> <3D8C1E99.74B9964D@earthlink.net> <3D8DC36E.516C8809@webaccess.net> <3D8EC823.7A1A0777@Physik.Uni-Muenchen.DE> <3D9033D3.992ED850@Physik.Uni-Muenchen.DE>
Date: Wed, 25 Sep 2002 06:59:37 GMT
NNTP-Posting-Date: Tue, 24 Sep 2002 23:59:37 PDT
Organization: EarthLink Inc. -- http://www.EarthLink.net
George Gonzalez wrote:
> Sorry, I see your reasoning, but IMHO it's a tad faulty:
> (1) The fact that atmospheric pressure will oxidize a getter does not tell
> us much what will happen at 0.0000000001 atmos. pressure.
> (2) One very old trick, to resuscitate a gassy tube, was to use a propane
> torch to heat the flashed area of the glass. This would sometimes do the
> trick. This would tend to indicate that cold getter material doesnt absorb
> much if any gas.
> (3) I too have seen power tubes with oxidized getters. It's not clear to me
> whether the getter was doing its job, or if the high glass tempeerature of a
> runaway gassy tube did the oxidation, or both.
> I'd say the evidence is inconclusive, either way.
Excuse me, the getter system worked only *once*, after the
manufacturer pulled a vacuum and sealed the tube, then the getter was RF
activated ("flashed"), evaporating some of the surface material.
That created an ionizes metal vapor which reacted with any oxygen and
adsorbed other gasses; the vapor depsoited on the inside of the glass,
making a silvery deposit.
If that deposit ever showed oxidation, then one knew for a fact the
tube was gassey and useless.