This circuit was found in a Popular Electronics from the 90's. The CMOS integrated circuit used is not very common nowadays. The range depends on the infrared LEDs. R7 can be changed.
This circuit is from the Motorola Linear Databook of 1990. The circuit controls a Triac from a...
The circuit shown uses the LM324, but can be implemented with other operational ones. The source...
This circuit makes use of a stroboscopic tube, a component that no longer exists today. The...