[R-390] Re: Refinishing meters

[Scott, Barry (Clyde B)]

Roy,

Well, I got quite a surprise last night.  I got the room completely dark and
looked at the meters.  Nothing.  A minute passed.  What's this?  A faint
glow??  Several more minutes passed and to my surprise, all four meters
glow!  It's faint, but it's there.  Presumably the stuff they coated it with
that did the actual glowing is all but gone but they still do glow however
dimly.

I had tried this before, but I didn't wait to let my eyes adjust.  Very
interesting.  Is it possible these are not radium-caused effects but simply
a process that absorbs light and then glows for a while?  I doubt it...

I plan to do some photography (the camera should pick up what my eyes
don't).

Thanks for the info.

Barry(III) - N4BUQ



Barry,

Many harmless meters are in fact "sealed" and are not intended to be opened 
for repair. I would not depend on the marking "Sealed do not open" as an 
indication one way or the other that the thing contains any radioactive 
material.

Instead, I suggest you do two things:

  1) Become familiar with the visual appearance of the radioactive 
markings. (Yellow-ish, thick, indistinct edges, may appear to have been 
dobbed on the surface over existing paint markings.)

  2) Look at the meter in the dark, complete darkness, after you have also 
been in the dark for at least 15 minutes to allow your eyes to 
adjust..  Also, try this after exposing the meter close range to the sun, 
or to a flourescent lamp (preferably a cool white one). This may 
"re-charge" the glowing material a bit.
<snip>