DEWAG make Neutron Monitor is designed to monitor neutron flux in a closed area. Neutron radiation is detected in a BF3 proportional counter which is embedded in a high density polythene moderator. Ionization charge from the detector is converted to voltage pulse signal in a charge sensitive pre- amplifier. Fast neutrons are thermalised into this moderator. The pre-amplifier is mounted right on the BF3 counter.
The pre amplifier output signal is then transmitted to the main monitor unit. The main monitor unit receives the pulse signal from the pre amplifier and after signal processing is given to frequency to voltage converter. The output voltage is proportional to the count rate from the detector. The linear output is then converted to a log converter which converts the 3 decade of count rate of counter output in to log scale.
Log output is then displayed on an analog meter which is calibrated in terms of neutron/Cm²/Sec. The analog output of the monitor is given to a microcontroller based RS485 interface which is connected serially to various monitors and controlled through an embedded web server in remote location/control room.