Model 977 Series Wide Range Ion Chamber Detectors
- Wide range ion chamber/preamp For use with Model 945A monitoring system Range: 10-1 to 107 mR/h Energy response: ±10% from 60 keV to 3 MeV Three twisted pair with overall shield connection to remote readout recommendedConsult factory for use with existing cable No local power supply required With preamp shielding
- For use with Model 945A monitoring system
- Range: 10-1 to 107 mR/h
- Energy response: ±10% from 60 keV to 3 MeV
- Three twisted pair with overall shield connection to remote readout recommended
Note: Consult factory for use with existing cable - No local power supply required
- With preamp shielding, life expectancy can be extended to approximately 107 rads
The wide range ion chamber detector design includes a single ion chamber with a volume of approximately 1000 cc. The chamber walls are made of tissue equivalent plastic. An outer wall, made of aluminum, is provided to protect the ion chamber and to mechanically interface with the Model 848-8 Field Test Source. The ion chamber is biased at a nominal 500 volts and produces an output current proportional to radiation absorbed in the chamber. The current is approximately 8 x 10-11 A/R/h. The ion chamber assembly makes use of a double seal design, where the actual ion chamber is back filled with nitrogen at atmospheric pressure. The connector area is sealed against moisture and particulates through the use of a sealed, liquid tight flexible conduit between the detector and preamplifier electronics. The preamplifier contains a microprocessor controlled, auto-zeroing, integrating electrometer, a programmable gain amplifier, an analog-to-digital converter, an asynchronous serial communications interface, an electronic check source, and the detector high voltage power supply. Communication with the Universal Digital Ratemeter (UDR) is accomplished via the optically isolated serial communication loop driver/receiver circuitry.