This circuit simulates a resistor controlled by digital signals. We found it in American documentation from the 90s. The basic component is a CMOS 4016 or 4066 digital switch.
This circuit was obtained from the February 1992 Radio Electronics magazine. In it, a bar of 4...
This circuit for the two-meter band of radio amateurs was found in 1980s documentation....
This programmable circuit emits a signal that can be sensed by the dog at a distance. The circuit is...