An electronic programmable clock timer permits a program of times to be set so that certain electrical functions either AC or DC, can be operated responsive to the times set. A high and low range temperature selector can be set to turn ON or OFF thus operating certain electrical functions such as heating, cooling, lights, etc. When in the selected operating time range, means are provided to eliminate operation of the device on certain days or within certain time periods. Extensive use is made of I.C. circuitry, including memory circuits, comparator circuits and the like.