ORANGE COUNTY

Walter A. Zarris has been appointed as the new president and chief executive officer of the Frequency & Time Systems Inc. subsidiary of Anaheim-based Datum Inc. He replaces Dr. Helmut Hellwig, who has been selected as associate director of the National Bureau of Standards in Washington.

For the last 22 years Zarris has been involved in the development and marketing of technological products, beginning with the communications division of East Coast-based E.F. Johnson from 1964 to 1974. He then co-founded Elcomex Co. Ltd. in Bangkok, a maker of quartz crystals, which he also served as president for five years. He later became president of Ferronics, a maker of ferrite components headquartered in New York State. Immediately before joining the Datum subsidiary, based in Beverly, Mass., Zarris had been acting as an independent consultant in the areas of general management and technology.

Datum Inc. manufactures frequency and timing devices for military and commercial applications.