580

Telecommunications Equipment-Namely, Multi-Frequency Remote Recall Units and Adapter-Intercom Units; Carrier Detector, Modulator and Demodulator Units for Digitized Data and Voice Signals; Pulse Code Modulated Carrier Systems-Namely, Channel Banks, Logic Units, Encoders, Decoders and Repeaters; Telecommunication Switching Systems-Namely, Private Branch Exchanges, Central Offices, Community Dial Offices, Automatic Call Distributors, Command and Control Stored Program Based Switching Controllers and Networks, Digital Pulse Code Modulated Switching Controllers and Networks, Remote Switching Units; Multiplexers and Demultiplexers; Printed Circuit Boards; Power Supplies; and Testing and Maintenance Units and Structural Mounting Components for All the Above Mentioned Items