Telephone privacy device with conference and indicator features
Telephone switch call control unit
Telephone switching system for easily implementing modification
Telephone system
Telephone system
Telephone system and speech level adjusting method therefor
Terminal based adjunct call manager for a communication system
Thermal management for a thin environmentally-sealed LCD...
Trading telephone
Trunk circuit with loop length gain equalization
Two line voice/data switch
Two-line apparatus for telephone intercom
Versatile communication device with a facsimile function and...
Voltage-sensitive telephone line monitor