A survey meter or area monitor with a spectrometer to separate pulses received from a detector according to pulse size. Pulse size is proportional to energy of the detected radiation. It typically consists of a detector (usually a scintillation or semiconductor detector), a linear amplifier, an analogue-to-digital converter (ADC), a computer memory for storing information from the ADC, a scalar or count rate meter. The memory permits automated data processing, e.g., background subtraction and spectrum striping, which permits the analysis of complex spectra.