All Forums  GQ Electronics Forums  2.GQ Geiger Muller Counter  GMC-600+ Reading too high for sample?

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Screensize: 640 x 480 800 x 600 1024 x 768 1280 x 1024 UserName: Password: Format Mode: Basic  Help  Prompt  Format: Font Andale Mono Arial Arial Black Book Antiqua Century Gothic Comic Sans MS Courier New Georgia Impact Lucida Console Script MT Bold Stencil Tahoma Times New Roman Trebuchet MS Verdana   Size 1 2 3 4 5 6   Color Black Red Yellow Pink Green Orange Purple Blue Beige Brown Teal Navy Maroon LimeGreen Message: * HTML is OFF * Forum Code is ON Smilies [quote][i]Originally posted by Rightfrog[/i] [br]I have a new GMC-600+ and recently ran it against a sample of uranium ore certified at 1109 CPM using a GCA-07W. The CPM number is "combined alpha, beta, and gamma radiation emissions". The measurement was taken at zero distance from the sample and at the highest reading spot. Just setting my unit over the container with the lid off is giving me a CPM of over 3000 and that's a consistent number after letting it measure over 3+ minutes. If I move the sample directly in front of the tube, it reads over 16000. I've tried setting fast estimate to 60 seconds (defaulted to dynamic) but it still reads > 3000. The unit seems to read background levels OK. On its own, it's usually 30-40CPM. What am I missing? [/quote]    Insert an Image File Check here to include your profile signature.