[Drake] cleaning dial of TR 3 and TR 4

[fkamp at comcast.net]

John King wrote:
> 
> One of my transceivers has a dirty or nicotine stained
> plastic dial. Has anyone successfully cleaned a Drake
> plastic dial without removing or destroying the
> numbers and letters on the plastic dials.
> 
> Please tell me your methods and experiences cleaning
> the dials. Thanks and 73, John, K5PGW
> 

I suppose it could be yellowed by nicotine, but my
experience has been that these dials yellow with
age regardless of environment.

It is some sort of reaction of the plastic
material due to exposure to heat (from the pilot
light) and sunlight.  The yellow is generally not
a surface film but goes through the plastic.

If you try to clean it all you will accomplish is
to remove the markings.

Regards,
Frank Kamp
K5DKZ