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.
With this circuit any number of 4017 integrated circuits can be connected in series. The circuit is...
This useful instrument has dual function, operating both as signal injector and continuity tester. The...
This circuit allows you to vary the duty cycle without changing the frequency. An interesting...