SBM20 Tube Hard Beta and Gamma Radiation GM Detector

Military  SBM-20  ( СТС-5 ;STS-5) Hard Beta and Gamma GM Detector (TESTED)Made in USSR Lot of  1  piece. SPECIFICATIONS:Working Voltage                                    360 - 440VInitial Voltage                                        280 - 330V Plateau Length                                      80VPlateau  Slope                                        0.125% / 1VInherent counter background (cps)       0.45 Pulses/sPulse Sensitivity                                     24 Pulses/sInterelectrode Capacitance                    7pFLoad Resistance                                     5 - 10 MOhmsWorking Temperature Range                 -40   +50 СLength                                                    110mmDiameter                                                 9mm