This circuit is from a June 1992 Radio Electronics. The circuit is for 4.5 MHz signals from old analog televisions or other similar applications.
An interesting and useful configuration for the control of power loads is shown in the figure. In this...
This circuit was suggested by Linear Technology in a 1980s documentation but can be implemented with...
This circuit, from a 1999 publication, uses an improvised optical coupler with LED or...