GN1221 Specifications

Energy Compensated Geiger-Mueller Tube.
Halogen Quenched, γ Radiation Tube.

Electrical Characteristics

Recommended Operating Voltage (volts)450
Operating Voltage Range (volts)400 - 600
Maximum Dead Time (μs)200
Maximum Plateau Slope (%/100 volts)15
Minimum Anode Resistor (MΩ)2.7
Recommended Anode Resistor (MΩ)3.3
Gamma Sensitivity Cs137 (cps/mR/hr)150
Max. Background Shielded 50mmPb+3mmAl (cpm)60
Tube Capacitance (pF)10

Mechanical Characteristics

Nominal Active Length (inch/mm)9.42 / 239.3
Window Thickness (mg/cm2)-
Active Diameter (inch/mm)0.83 / 21.1
Cathode MaterialCr - Fe
Cathode Wall Thickness (inch/mm)0.025 / 0.64
Operating Temperature Range (°C)-40 to 70
Fill GasNe/Ar + Halogen
Type of ConnectorFlying Leads
Approx. Weight (grams)350
Maximum Altitude (ft)TBD

Equivalent models: ZP1221 , 7807

Global Nucleonics has the design and engineering capability to produce detectors to your specifications.