Radiation Detection

Oh, I see that all the time... Bad crystal. Used Ludlum 44-2 are often found with bad 1X1 crystals, and one way to quickly diagnose is to see the response to a low energy source like Am241. With a good crystal (and good PMT), you should have gotten plenty of counts at less than 800 volts using an Am...

Chris - Please check out your "Private messages" from me and contact me at my email address. Thanks, Tom

Peter - I've actually never seen that happen and have soldered directly to the pins of thousands of PMTs. Perhaps it is possible by using excessive heat and/or poor soldering technique, or excessive stressing of the pins with certain especially fragile PMTs, but it is not something to usually worry ...

Cool effect indeed, but I'm guessing only finding 2 such samples over your many years is a good thing in this instance. :)

Your first question... Just based on what I can see, and without an available datasheet, I'd guess probably not. 2nd question... I'm guessing the coax with the BNC is signal out, and the leads terminating in the green connector are HV. This scheme "might" be compatible with the GS-USB-PRO ...

Andrey - This is one of the nicest and most useful projects for field detecting I've seen recently. You and Charles have done an excellent job with its design and construction. I really like the idea of variable tones combined with a squelch control. FANTASTIC!

Hi Andrey -
Nicely documented build, and very nice results. The larger detector is a nice addition to your stable.

Here is LaBr3 2X2 detector with background in grey and 5 pounds of Kitty Litter in Green.

It's still possible to pick out the Cs134 peaks from Fukushima with LaBr3...

Hi Tim, and welcome to the group Of course, I’m sure you know light needs to travel from the crystal to the PMT. To get there, it must pass through several surfaces. Usually on the crystal there is a glass window, then there is an air gap between the glass window of the crystal and the glass window ...