This circuit for a digital module was found in the September 1989 Radio Electronics magazine. The source must be symmetrical to the operational amplifier.
This circuit was found in an 80's Electronic Engineering. The circuit uses a multivibrator with...
Figure bellow shows how many 40293 can be cascaded. The input CI of the first circuit is grounded. The...
This circuit is from Motorola documentation, but can be implemented with virtually any...