Bob - Tempilaq, or Omegalaq when it is bought from Omega, can be used to
measure your 4-1000A seal temperatures if applied carefully. I have not used it
with glass tube envelopes, only ceramic/metal. Several things must be done.
Make sure the paint is liquid enough to apply a thin film of a coating. Make
the marks very small. If the stuf is thickened, then appy their approved
Thinner and shake well. You don't want a thick dot or blob. As you know, when
the temp is reached, the paint will run and change color/appearance. I usually
use 125, 150, 175, 200 deg C paints when measuring power tube seal temps. Apply
them in several locations around the tube, in clusters of the colors that you
can later look at and identify which has run. This might identify hot spots
such as when using connections for RF cavities which only contact one side,
etc. Try not to bridge over large portions of the tube, just keep it in small
clusters. I am not certain how glass will handle the paint on it,
guess is as good as ceramic if you keep the dots or smears very small, <3/16
inch, perferable smaller. Put the dots near where electrodes poke through the
glass. Even better put them on the metallic posts sticking out.
> Message: 8
> Date: Mon, 27 Aug 2007 17:27:57 EDT
> From: W7lr@aol.com
> Subject: [Amps] temperature
> To: firstname.lastname@example.org
> Message-ID: <email@example.com>
> Content-Type: text/plain; charset="US-ASCII"
> I purchased a used HF amp with a 4-1000A but no blower. To verify that the
> blower I have is adequate I would like to measure seal temperatures. I
> believe that this can be done using Tempilaq. How successful is doing that?
> maximum seal temperatures are 150C for the base and 200C for the plate. To
> be conservative, I expect to use tempilaq laquer values well below those
> temperatures. What values of temperature do you usually experience with an
> adequate blower? If you have the model of such a blower that would be
> helpful too.
> Thanks. Bob W7LR firstname.lastname@example.org
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