H04Q 5 - Selecting arrangements wherein two or more subscriber stations are connected by the same line to the exchange

Patents for H04Q 5 - Selecting arrangements wherein two or more subscriber stations are connected by the same line to the exchange (6,717)
09/1979
09/06/1979	WO1979000648A1 Telephone system with a plurality of internal extensions and a plurality of outside lines
09/04/1979	US4166931 Miniature bridge lifter for telephone lines
06/1979
06/12/1979	US4158111 Exclusion system for a key telephone system
05/1979
05/15/1979	US4154987 Party intercept in selective multifrequency ringing systems
01/1979
01/23/1979	US4136263 Telephone system having space divided speech channels and a separate time divided data highway
11/1978
11/28/1978	US4127824 Sampling filter-detector
08/1978
08/22/1978	US4109112 Telephone isolation device
07/1978
07/25/1978	US4103114 Variable delay ringing detector
11/1977
11/01/1977	US4056694 Telephone ringing detectors
09/1977
09/13/1977	US4048551 Battery charging circuit
09/13/1977	US4048448 Multiparty telephone ringing
05/1977
05/03/1977	US4021617 Telephone ringer isolator
08/1976
08/10/1976	US3974342 Switching arrangement for telecommunications systems
03/1976
03/30/1976	US3947819 Apparatus for expanding channel output capacity
03/02/1976	US3941933 Paging intercommunication system
02/1976
02/17/1976	US3939308 Electronic side of line detector
02/03/1976	US3936614 PBX ground start trunk interface for station carrier systems