Digital Cardiac Period Meter With DA Converter

Abstract

A new type of cardiac period meter, which allows the simultaneous collection of digital and analog records, was designed. The wave‐shaper and the pulse sequencer in a digital counter were modified for the purpose of measuring successive heartbeat intervals. The output terminals of the counter were connected directly to a digital‐to‐analog (DA) converter. The pen‐oscillograph record of the analog output produces a stair‐case waveform characterized by sharp edges and stable horizontal lines.