Re: Light Sensitive GM Tube

[Stan <swilson@emory.edu>]

Not exactly, but I have observed the same phenomenon in an 
Ebeline HP-190 which had been well used, and probably had 
been subjected to overvoltage ~1100 kV at least 
once.... photoelectrons? 

:>---                                                       ---<:
Stanley L. Wilson, M.M.Sc	            Phone (404)-727-0729
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On Thu, 25 Jul 1996 epombier@mednet.med.miami.edu wrote:

>      We have a Ludlum Model 44-7 thin end window G-M detector which appears 
>      to have become light sensitive.  When the window is exposed to bright 
>      light you get a significant response.  If you mask half of the window 
>      you find that the response varies as you rotate the mask.  The 
>      detector still responds appropriately to radiation and the background 
>      is not inordinately high at normal indoor lighting levels.
>      
>      Any thoughts as to the cause of the phenomenon.
>      
>      Ed Pombier
>      Director 
>      University of Miami Radiation Control Center
>      (305) 243-6369
>      epombier@mednet.med.miami.edu
>