Manufacture of computer hardware, electronic devices and electronic assemblies, namely, acoustic, sonar, radar, tactical, combat, navigational and infrared signal processors, recorders and sensors, acoustic video display systems, mission data recorders, optical systems, complex cables, cable harnesses and circuit cards, magnetic broadcast audio heads, magnetic flight recorder heads and magnetic strip card readers to the order and specification of others, namely, military, industrial and commercial users; manufacture of commercial video recording products, to the order and specification of others, namely, for television and post-production facilities