PDT10A and PDT20A compact neutron monitoring modules designed for high radiation environments connect directly He-3 detectors. Each instrument contains a precision wide band charge sensitive pre-amplifier followed by an amplifier, wave shaping and discriminator circuits. When connected to He-3 detectors, these instruments detect the presence of charged-sensitive particles. Our focus is to create a compact (1 inch diameter), simple to use, high perbance instrument with a variety of features available.