P

Assignee

TIE COMMUNICATIONS

US20 patents

Top patents by PatentIndex Score

US4740955AApr 26, 1988

Communications system having voice and digital data capability and employing a plurality of voice and data buses in main service unit and serial packetized transmission to and from telephones

TIE COMMUNICATIONS101 citations91
US4173714ANov 6, 1979

Communication circuit with combined power feed and data transmission over a phantom channel

TIE COMMUNICATIONS91 citations91
US4667142AMay 19, 1987

Three-way power source circuit

TIE COMMUNICATIONS35 citations90
US4203011AMay 13, 1980

Computer controlled key telephone station set

TIE COMMUNICATIONS32 citations88
US4577310AMar 18, 1986

Station interface for digital electronic telephone switching system having centralized digital audio processor

TIE COMMUNICATIONS38 citations87
US4338495AJul 6, 1982

Electronic key telephone systems

TIE COMMUNICATIONS21 citations77
USD307418SApr 24, 1990

Telephone base

TIE COMMUNICATIONS7 citations72
USD299460SJan 17, 1989

Telephone set

TIE COMMUNICATIONS6 citations72
USD299458SJan 17, 1989

Telephone set

TIE COMMUNICATIONS9 citations72
USD299459SJan 17, 1989

Telephone set

TIE COMMUNICATIONS11 citations72
US4341927AJul 27, 1982

Data transmission apparatus

TIE COMMUNICATIONS14 citations71
US4757521AJul 12, 1988

Synchronization method and apparatus for a telephone switching system

TIE COMMUNICATIONS14 citations68
US4715062ADec 22, 1987

Speakerphone control circuit having low gain states and method for controlling gain of speakerphone

TIE COMMUNICATIONS17 citations68
US4140877AFeb 20, 1979

Muliple highway time division multiplexed PABX communication system

TIE COMMUNICATIONS20 citations68
US4894860AJan 16, 1990

Trunk interface circuitry for telephone systems

TIE COMMUNICATIONS11 citations63
US5081329AJan 14, 1992

Key assembly, switch assembly and method of making same

TIE COMMUNICATIONS18 citations60
US4773068ASep 20, 1988

Dual channel transmission method and apparatus with inherent channel identification and extraction

TIE COMMUNICATIONS3 citations60
US4679228AJul 7, 1987

Speakerphone sensing circuit

TIE COMMUNICATIONS6 citations60
US4674118AJun 16, 1987

Telephone line hold and hold release apparatus

TIE COMMUNICATIONS5 citations60
US3963879AJun 15, 1976

Telephone dial assembly

TIE COMMUNICATIONS1 citations51