Thermo/Eberline Model RO-20 Ion Chamber

Ion Chamber radiation meter

Radiation Detected: : Beta, gamma, and xray.
Ranges: : Five linear ranges: 0-5, 0-50, 0-500 mR/h and 0-5, 0-50 R/h
Meter: : Scale length, approx. 3 inches (7.6 cm), 2% accuracy. Linear markings from 0 to 5 in 50 minor increments. The meter is back-lit. Response Time: : 90% of final reading within 5 seconds
Linearity: : Within ± 5% of full scale.
Battery Dependence: Reading is independent of battery voltage when the battery check indication is in the green arc.
External Controls: : Range switch, including Off, Zero, and Battery checking positions. Zero knob used to set meter to zero when Zero position of range switch is selected or when in no significant radiation field. Light switch, for meter light.
Internal Controls: : Five calibration controls, one for each range. Batteries: : Main power: Five "C" cells.
Chamber Bias: : Ten 3 volt lithium coin cells, 30 volts.
Temperature: : Operable from -40 °F to 140 °F ( -40 °C to 60 °C). For operation below 0 °F (-18 °C), alkaline or nickel-cadmium "C" cells should be used.
Temperature Compensation: The detector is fully compensated over the operational temperature range for output accuracy within 10% ±0.5 mR/h.
Humidity: : Operable from 0 to 95%, non-condensing
Weight: : Approximately 3.6 pounds (1.63 kg) with alkaline C cells.
Size: : 4.2” wide x 7.9” long x 7.7” high (107 mm x 201 mm x 196 mm), including handle.