We found this circuit in the July 1988 Radio Electronics magazine. The frequencies are given by capacitor C1 and the voltage input is made at pin 1.
This circuit of an EDN divides the input pulse frequency by even values. The circuit is TTL and...
This circuit, which appears from other sources on this site, converts a voltage into a current....
This circuit cut the noise peaks by means of diodes so that they do not appear in the output...