We found this circuit in the September 1992 issue of Radio Electronics magazine. It can be triggered by any signal above ½ Vcc, where Vcc is the supply voltage.
The Toshiba TLP577x series consists of an infrared photo-emitter (IR) and a sensor integrated circuit...
This circuit allows the measurement of very weak currents indicated on an analog instrument or...
This circuit is from a 1988 publication, but we can assemble it with some component changes. For...