[R-390] meter luminescence

[rbethman]

Specifics on the CDV-700 Model:

The CD V-700, as a true Geiger counter, is capable of measuring ambient 
background levels of gamma radiation and detecting the presence of beta 
radiation in the environment, and thus can be used to detect such common 
low-level radioactive artifacts as uranium-doped marbles, Fiestaware 
plates and radium watch faces. This differentiates them from other civil 
defense radiation meters such as the CD V-715, CD V-717 and CD-V-720, 
which are ion chamber meters that can measure gamma radiation levels far 
above (up to 500R/h) what the CD V-700 can (up to 50mR/h). Conversely, 
the ion chamber units are so insensitive to low-levels of gamma 
radiation that no legally exempt radiation source can make them register 
at all.

This makes them rather useless for use other than Nuclear warfare.  
Which is precisely what they were designed for, and have not been 
produced for over 50 years.

Bob - N0DGN


On 1/15/2014 1:27 PM, Adam Vaughn wrote:
>   (apologies for the blank messages; it seems that the mailing list does not agree with my email system's online client, for some reason)
>
> The meters on my '67 EAC R-390A have lighter-colored markings than the meter on my '51 Collins R-392. The R-390A meters do indeed show a small, brief amount of green glow when exposed to a bright light source, such as a camera flash; the R-392's meter shows nothing. Testing with my Cold War-era Victoreen CDV-700 geiger counter shows very little radiation from the R-390A's meters, while the R-392's meter is very 'hot'. The substance in the paint on these meter markings which actually glows is apparently zinc sulfide, which degrades much quicker than the radium which induces the glow
> -Adam
>
> --
> Adam Vaughn
> Collector of old computers, video game systems, radios and other electronic
> equipment...
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>