[R-390] meters arrived

[2002tii]

Brian wrote:

>He also told me from 1962 onwards, the spec on r-390a meters changed from
>"s" for self-luminant to "p" for "phosphorescent", which means there may
>well be many 390A meters pulled that are not radioactive at all.  How to
>tell the diff, I haven't a clue...

Leave them in the dark for a day or two, then see if they glow.  If 
yes, they are self-luminant (radioactive) meters.  If no, they MAY be 
phosphorescent (or they may just be old, tired self-luminescent meters).

Or, just use your Geiger counter.  You do have one, don't you?

Best regards,

Don