During the period from May 1957 to July 1958, four nuclear batiery powered timers were fabricated and tested from two basic designs in the time ranges of onesecond, three-second, and half-hour intervals. The timers were temperature-tested over a range of -65 to +165 F with accuracics over this temperature range from plus or minus 10 perceat to plus or minus 15 percent. Each unit has a volume of 10 cubic inches, and the timer can be initiated either by an explosive squib or a pull-out wire. At the end of the timing interval, the timer has ann output of 30,000 ergs. The cost of the program was,000. From the results of this development program, it appears quite feasible to build operable nuclear battery powered timers on a production basis.

Included are 88 references on thermionic conversion of heat energy and the use of radioisotopes as power sources. References on thermoelectric conversion are included if the primary energy source is a radioisotope.