installation and repair of wired and wireless message, voice and data communications, storage and retrieval systems

computer programs for use in the field of communications; DC-DC converters; power supplies; message administration systems comprising a telephone exchange terminal, a printer, a port concentrator, and a number of computer screens and keyboards; controllers for communications systems; radio transmitters; radio receivers; radio transceivers; radio repeaters; radio tone encoders and decoders; telephone and radio modems; paging terminals; voice message terminals; radiotelephone base station termi...

PAGING AND VOICE MESSAGE TERMINALS; TELEPHONE MESSAGE ANSWERING TERMINALS; RADIO MODEMS; RADIO REPEATERS AND BASE STATIONS; RADIO PAGING TRANSMITTERS AND REPEATERS; RF POWER AMPLIFIERS [ ; TELEPHONE CABLE TEST UNITS ]

Apparatus for Locally and Remotely Monitoring Data Associated with the Operation of a Vehicular Transportation System; Interrogator/Transponder Apparatus; Telephone Central Office Apparatus; Power Supplies; DC-DC Converters; Industrial Control and Monitoring Consoles and Panels; Mobile Mounting Racks for Electronic Apparatus; Mobile and Base Station Radiotelephone Apparatus-Namely, Mobile Radiotelephone Control Heads, Base Station Radiotelephone Terminals, and Mobile and Base Station Tone Enc...