Differential nonlinearity compensation enables the design of a low-cost networked MCA

An algorithm to compensate for the differential nonlinearity of an inexpensive integrated-circuit analog-to-digital converter (ADC) made it possible to develop a simple, low-cost multichannel analyzer (MCA). The cost is low enough ($250) to allow the use of an MCA per head in a plutonium continuous-air-monitoring (CAM) system. Multiple heads are connected to a standard personal computer via a simple networking scheme to allow a single computer to control a number of heads. The power requirements are low enough for the heads to be powered from a single power supply over the network cable. The system provides improved detectability, lower false alarm rates, lower installation costs, and lower maintenance. It is self-diagnosing for common problems and can even set its own filter change intervals. The authors discuss the design development, the circuit design, the software, and the performance