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 # Geiger-interface
 
+### J3x5 Tube specification
+| Property                                   | J3x5                                 |
+|--------------------------------------------|--------------------------------------|
+| Radiation type                             | beta, gamma                          |
+| Dimensions (max), mm                       | d11 x 107                            |
+| Country of Origin                          | China                                |
+| Vendor’s calibration<br>radioactive source | Co-60                                |
+| Sensitivity                                | 44 CPS at 1 mR/h<br>Co-60            |
+| Dead Time                                  | TBD                                  |
+| At the background level                    | 25 pulses/minute                     |
+| Internal background <br>noise              | 0,2 pulses/s<br>12 pulses/minute     |
+| Recommended operating<br>supply voltage    | glass tube 380 V<br>metal tube 400 V |
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