Scientific instrument consisting of an electronic circuit that permits only voltage pulses of predetermined height to pass WordNet 3.0 & Open English WordNet

A pulse-height analyzer is an instrument that accepts electronic pulses of varying heights from particle and event detectors, digitizes the pulse heights, and saves the number of pulses of each height in registers or channels, thus recording a pulse-height spectrum or pulse-height distribution used for later pulse-height analysis. Wikipedia

An electronic instrument Wikipedia Disambiguation

Nuclear electronic instrument for sorting gamma rays or charged particles into bins by energy, counting them, and saving the spectrum of pulse heights obtained for further analysis Wikidata

A device for analyzing the amplitudes of electrical pulses. Wiktionary