Patents
Patents for H04Q 1 - Details of selecting apparatus or arrangements (11,745)
06/1980
06/03/1980CA1078980A1 Circuit arrangement for a digital multifrequency-signal receiver
05/1980
05/27/1980US4205203 Methods and apparatus for digitally signaling sounds and tones in a PCM multiplex system
05/20/1980US4204095 Telephone main distributing frame
05/20/1980US4204094 Tone applying line circuit
05/14/1980EP0011018A1 Recognition apparatus and method for a digital multi-frequency signal receiver
05/14/1980EP0010922A1 Device for determining periodic components of an alternating signal
05/14/1980EP0010783A1 Method and device for detecting the presence of one or more MFC-frequencies within a PCM-signal
05/14/1980EP0010720A1 Fully electronic loop closure circuit
05/13/1980US4203008 Digital signalling receiver for receiving PCM tones
05/06/1980US4202029 Transportable telephone exchange apparatus
05/06/1980CA1077162A1 Mounting device for electrical connectors
05/01/1980WO1980000905A1 Minimum break/make pulse corrector
04/1980
04/30/1980EP0010344A1 Digital signal detector
04/29/1980CA1076649A1 Interface for in band scpc supervisory and signalling system
04/22/1980US4199729 Variable peak detector
04/15/1980US4198547 Pulse circuit for two wire electronic PABX stations
04/08/1980US4197502 Digital signal detector
04/08/1980US4197434 Telephone exchange apparatus
04/02/1980EP0009124A1 Arrangement for subscriber circuits of digital time multiplex telecommunication systems, in particular of local PCM telephone exchanges
04/01/1980US4196321 Loopback test system
03/1980
03/18/1980US4194092 Device for detecting a frequency in a PCM coded signal
03/04/1980US4191862 Dual frequency tone decoder
02/1980
02/26/1980CA1072695A1 Telephone tone signalling receiver
02/26/1980CA1072671A1 Electrical connector block
02/26/1980CA1072670A1 Cross-connection assembly for communications wires
02/26/1980CA1072659A1 Electronic trunk scanner
02/20/1980EP0008220A1 Dual frequency tone decoder system interface
02/20/1980EP0008160A1 Programmable digital tone detector
02/05/1980US4187414 Circuit arrangement for an interference data alarm system in communication facilities, particularly in telephone equipment
02/05/1980US4187403 Voice-protected, frequency-selective signal receiver
01/1980
01/29/1980CA1070840A1 Cross-correlation arrangement
01/23/1980EP0007122A1 Forced-air cooling of an electronic assembly
01/22/1980US4185172 Method of and means for detecting digitized multi frequency-coded signals
01/22/1980CA1070430A1 Method and apparatus for generating digital dual frequency signals
01/15/1980US4184053 Ringing signal detector
01/08/1980CA1069599A1 Distributing device for a multiconductor cable
12/1979
12/18/1979US4179170 Connector assembly for telephone distribution equipment
12/11/1979CA1068021A1 Digital testing and power control in a digital communication system
12/04/1979US4177359 Post wire guide latching means
11/1979
11/27/1979US4176286 Signal translator with squelch
11/27/1979US4176257 Telephone connector block
11/13/1979US4174466 Multi-party telephone system allowing speech connection between extensions as between extensions and an outer line
10/1979
10/30/1979CA1065417A1 Sampled signal detector
10/23/1979CA1065041A1 Mounting apparatus for a telephone exchange unit
10/16/1979US4171466 Digital wave generator for composite tone
10/16/1979CA1064633A1 Receiver apparatus for detection of two voice frequencies in a multifrequency tone signal
10/04/1979WO1979000728A1 Signal translator with squelch
10/02/1979US4169969 Apparatus for detecting in-band signalling signals
09/1979
09/25/1979US4169221 Method and apparatus for testing a subscriber line group marker of a telephone central office cross bar switching device
09/25/1979CA1063272A1 Multifrequency signal parity detector
09/18/1979US4168515 Line protector for a communications circuit
09/18/1979US4168402 Electronic trunk selector
08/1979
08/28/1979CA1061490A1 Dial impulse relay circuit
08/28/1979CA1061440A1 Call processing restoration arrangement for telephone switching system
08/21/1979US4165450 Telephone signalling test system
07/1979
07/24/1979CA1059246A1 Holding circuit in a receiver for detecting two frequencies in a multifrequency tone signal
07/24/1979CA1059231A1 Modular distribution frame assembly
07/17/1979US4161630 Circuit arrangement for use in telephone systems
07/17/1979CA1058784A1 Digital decoder for multiple frequency telephone signalling
07/10/1979US4160880 Modular termination system for communication lines
07/10/1979CA1058313A1 Telephone distribution frame connector assembly
06/1979
06/19/1979US4158754 Mounting apparatus for communication exchange equipment
06/12/1979CA1056525A1 Pay telephone applique for subscriber carrier telephone system
06/12/1979CA1056505A1 Receiver for voice response system
05/1979
05/08/1979US4153847 Logic circuits
05/08/1979US4153819 Telephone tone signalling receiver with up-conversion of frequency of tones controlled by word instructions
05/01/1979US4152749 Matrix terminal block
05/01/1979CA1053821A1 Receiver/sender for signalling between telephone switching facilities
04/1979
04/24/1979US4151472 Selective calling circuit employing controlled power supply therefor
04/24/1979US4150867 Pre-wired terminal connecting block
04/24/1979CA1053389A1 Mfc receiver digital signal processing
03/1979
03/27/1979US4146755 Protecting for low voltage lines, in particular for telephone networks
03/27/1979US4146751 Solid state pulsing apparatus for pulsing selected line relay terminals
03/20/1979US4145580 Multi-frequency signal receiver
03/20/1979US4145576 DTMF and rotary dial signal receiver
02/1979
02/27/1979US4142177 Digital tone decoder system
02/22/1979WO1979000066A1 Multifrequency signal receiver
02/20/1979US4140885 Modular interchange termination system
02/20/1979US4140880 Hold tone scanner
02/13/1979CA1048628A1 interface and control system for telecommunication center
02/06/1979US4138599 Modular communication system having self-identifying modules
02/06/1979CA1048184A1 Pulse duration correction circuit
01/1979
01/30/1979CA1047611A1 Digital tone detector using concatenated detection intervals
01/23/1979US4136356 Wiring substrate for a matrix circuit
01/16/1979US4135062 Electric network for use in a subscriber's loop
01/09/1979US4133982 AC supervisory signal detector circuit
01/09/1979US4133979 Multifrequency sender/receiver in a multi-time slot digital data stream
12/1978
12/26/1978US4131934 Receptacle fixture for equipment units in electrical communication technology
12/26/1978US4131330 Mounting device for electrical connectors
12/19/1978US4130736 Telecommunication system with keyboard selection
12/12/1978US4129756 Telephone exchange signalling unit
11/1978
11/28/1978US4127748 Cable transfer panel
11/21/1978CA1043024A1 Multi-frequency signaling decoder
11/07/1978US4124898 Programmable clock
11/07/1978CA1042108A1 Tone detector using spectrum parameter estimation
10/1978
10/31/1978CA1041671A1 Serial digital bit stream code detector
10/24/1978US4122313 Telephone connector cutover block
10/17/1978CA1040732A1 Thyristor circuitry for providing automatic number identification services
10/10/1978US4119808 Multi-frequency receiver circuits
10/03/1978US4118091 Electrical connection assemblies