The applications of neutron monitors extend to many critical fields such as leak detection in nuclear power plants, cosmic ray detection for space-weather monitoring, and homeland security in preventing the unauthorised transport of nuclear materials. The industry standard neutron monitor technologies are based on helium-3 but due to the volatile price and scarcity of this rare isotope, the production of these detectors, and scaling of projects involving them, is unsustainable and expensive. It is therefore valuable to explore and develop alternative technologies. Commercially available signal processing systems are costly and lack versatility, so this project aims to facilitate the scaling of neutron monitor networks by providing a platform for low-cost electronic systems for their operation. The project involves the final stages of development of a preamplifier and shaping amplifier system created for use with a PTI-110 boron-coated-straw neutron monitor and the verification and evaluation of its functionality with the use of a californium-252 neutron source. A second version of the preamplifier and shaping amplifier was created for use with high count rates (>1000cps) which incorporates a novel slew-rate-limited shaping architecture allowing few components to be required. The adverse effects of capacitor leakage and operational amplifier bias current are explored, and solutions are found to negate them. Testing showed the preamplifier and shaping amplifier has a desirable response curve whereby the amplitude of the output voltage pulse is directly proportional to the magnitude of the input charge. Furthermore, the system produces a desirably shaped pulse approximating a gaussian curve. A pulse height spectrum that is consistent with other similar detectors was obtained by exposing the detector to a neutron source. The shaping-time and gain of the system are widely variable by altering values of passive components. The project provides a low cost (£10), customisable platform for proportional counter tube operation with suggestions for alternative configurations and further optimisation.
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