Found on a 1969 EDN this circuit switches a current from a digital control signal. The impedance of the circuit ON is approximately 10 ohms. Modern equivalent transistors may be used.
The presented logical configuration uses one comparator of the four existing in an LM139 or...
This circuit was found in a 1987 publication. A 4017 sequentially counts time in steps set by...
This wideband circuit with the 4046 PLL was found in the December 1989 Radio Electronics magazine. The...