Sinus-, Rechteck- und Dreieckgenerator (für Audiofrequenzen)

Programmable frequency dividers are particularly useful for producing a large number of frequencies from one reference frequency. An example of the type of circuit in which such dividers can be used is a frequency synthesiser. Programmable dividers are generally rather expensive. The circuit given here offers a less pricey solution. In this instance, two 7490s connected in cas- cade are made programmable by provid- ing a switchable reset point.