Abstract: An autocalibrating multichannel analyzer (MCA) for spectroscopy. The autocalibrating MCA includes a data collection unit, wherein is included a detector and a multichannel buffer (MCB). The detector produces an analog signal representing selected parameters of a radioactive sample. The MCB includes a signal conditioner for converting the analog signal into a digital signal and a processor for sorting and counting the signals received from the detector. The interface unit includes a processor for data analysis, at least one output device to display information, at least one input device to accept commands, at least one memory device for storing data, and an automatic calibration system to correct data for errors introduced by the data collection unit and the surroundings. The automatic calibration system compares parameters collected from a known calibration sample against parameters stored in the system with little intervention by the operator.