This heartbeat sensor circuit was found in the July 1992 issue of Radio Electronics magazine. The circuit uses a 741 with a single power supply.
May 2017 - Panasonic's new APS1 series of optical couplers with 3 750 V insulation and up to 50...
Found in an EDN from the 90s, this circuit uses an electret microphone. The output can be used to...
The purpose of this circuit, found in a 1994 documentation, is to provide resources for testing...