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Old fashioned vacuum gauge

So Bettina doesn't feel alone with the anti-gauge label I will state my reasons
for not have a vacuum gauge on my system. Around 20 years or so ago I read this
book by Sam Miller where he says on page 183...Pump the tubes down until only a
barely visible glow occurs when the test coil is applied. If the pumps will not
reach this degree of vacuum, or if they require too long a time to reach it,
there is something wrong with the system. He then goes on to say... When the
tube has been pumped out to the required degree of high vacuum (five microns or
less), the main-pump stopcock is closed. He includes this fancy table 10-1
"Degree of Vacuum by Color, Using a Spark-coil Tester". All of this time I have
been a believer in this method. I can tell you that my tubes last for a very
long time (at least 20 years now of continuous burning) using this method. The
Table defines 5 microns as when the blue discharge disappears and no glow is
visible in the tube with a blue haze near the glass wall. 

What I like about this system is it's simplicity and the fact that it NEVER goes
out of calibration. It relies on powers of observation and one of my
favorites... the laws of physics. I really don't think it matters what method
you use as long as it works for you and you are certain that you understand the
pumping process and you are not having any problems with units aging up
immediately or failing prematurely in the field.

On the Tempilaq, unlike the crayons, it goes clear from opaque so it is very
easy to see when the change happens (especially when the tube is lit during
bombing). Maybe Tecnolux will consider selling the stuff... If not, I can
probably order it in some quantity next time. It lasts so long we don't order
very often. As for UV or HV affecting it in an adverse way, I doubt that. 

Bettina, as for your question about phosgene, I don't know enough about what is
in Sta-Zon to be able to tell you about break down by products. It doesn't sound
right to me thought. Maybe another source at the same site (nah, nothing like
that in Brooklyn). Any idea why the shop blew up?


  - Tom Biebel, 19-Feb-1996
  - Neoman
  - Plasma Graphics Neon