Bicron Internal Voltage Divider

[Addison.G]

I purchased a small square Bicron NaI(Tl) scintillator (.5X.5M3/.5L-X) a few months ago to use for general surveying. While it works well for the most part for that purpose, I've realized the voltage divider is too low of a resistance to pair well with my current meter so I'm considering modifying the voltage divider. I can unbolt the back cover and look inside but I'm concerned in case the crystal is unencapsulated. Does anyone have any familiarity with these particular scintillators and what I might expect if I open it up?

[Sesselmann]

Addison,

Yes, your suspicion is correct, the crystal is not encapsulated and the PMT's are glued directly to the crystal with a piece of glass and epoxy.

If it works I recommend leaving it, but if you really want to modify it you have to cut the top off and work on the PMT in situ.

Steven

[Addison.G]

Steven,

Thank you for that information. I'd seen conflicting information about similar detectors with some being built like you said and some having a removable crystal/pmt.
I somewhat misspoke when I said it worked, it loads the meter down fairly heavily requiring the meter have very fresh batteries and leaving count rates unstable as the batteries are used up.
Based on how you describe it, would you think there's a high likelihood of damaging the crystal if I unbolt the back cover or should I start looking at rigging up a glovebox with at least a very dry if not inert atmosphere.

Addison