We found this circuit in a 1965 Electronic Design. Transistors are still common but admit equivalents for some of them. The circuit drains a current of only 4 mA.
This circuit was obtained in an old American manual. The circuit is valid for any operational. The...
This two-relay circuit gives drive logic that is clear when analyzing the circuit. In the original...
This circuit, suggested by Philips Components (1980), uses a fast voltage comparator and requires...