[R-390] Tube Shield Painting

[chuck.rippel at cox.net]

Painting the INSIDE of the nickel shields flat black helps.  Its an old 
trick used in RF amplifiers which employ glass tubes.  The idea is to 
paint the
surfaces around the tubes flat black so that infra-red heat from the 
tubes is absorbed and not reflected by what may be shiney metal surfaces 
back into the dark structure
of the tube itself.

Its not an IERC or WPM shield which actually wicks heat off the tube 
bulb itself but better than nothing.

---
No  trees were killed to deliver this message.  However, a large number 
of electrons were terribly inconvenienced.

Chuck Rippel



> I wonder about the idea of painting shields to make them black.
> Wouldn't the thickess of the paint polymer act as an insulator?
> The black IERC shields look like they've been anodized black
> which is a lot thinner.
>
> Cheers, Gord VE3EOS