This circuit uses a photo-SCR or LASCR that is not a common component today. The relay depends on the load, and the power is supplied by the power grid.
This circuit produces the ticking of a clock on a common piezoelectric transducer. The circuit has an...
The basis of this circuit is a double T in the feedback, which has the components calculated to...
This configuration was found in the Texas Instruments optoelectronics manual. PNP transistors...