Patents
Sitemap › H04 - Electric communication technique › H04Q - Selecting › H04Q 1 - Details of selecting apparatus or arrangements
Patents for H04Q 1 - Details of selecting apparatus or arrangements (11,745)
10/1981
10/21/1981EP0038256A1 Switch with several crosspoints layers
10/13/1981EP0031369A4 Dialing interval transmission gating arrangement.
10/13/1981CA1110788A1 Telephone set with loop current interruption timing control
10/07/1981EP0037222A1 Line protector for a communications circuit
10/07/1981EP0037048A1 Signal affirmation device
10/07/1981EP0036979A1 Signalling process for telecommunication exchanges, especially telephone exchanges
10/06/1981CA1110349A1 Digital multifrequency signalling receiver
09/1981
09/29/1981US4292473 Loop supervision circuit
09/16/1981EP0035564A1 Binary coincidence detector.
09/08/1981US4288664 Neutralization signal developing device for an echo suppressor
09/08/1981US4288660 Test cord for telephone circuits
08/1981
08/26/1981EP0034336A1 Digital frequency transmitter
08/25/1981US4286326 Digital devices for spectrum analysis
08/25/1981US4286221 Multi-frequency signal receiving apparatus
08/25/1981US4286121 Telephone line cutover apparatus and switch
08/19/1981EP0033933A2 Process for feeding audible tones into conference communications
08/18/1981US4284853 Telecommunication subscriber line access circuit with ground key indication and a device for call signal generation
08/04/1981US4281885 Line telecommunications cable end system
08/04/1981CA1106513A1 Telephone signalling test system
07/1981
07/29/1981EP0032741A1 Circuit for transmitting signals to and from a subscriber of a private telephone branch exchange
07/22/1981EP0032365A1 Supervision device for a digital signal generator
07/14/1981US4279017 Method and device for detecting the presence of one or more pulse code modulated multi-frequency code signals
07/14/1981US4278842 Circuit for eliminating spurious pulses in a dial pulse stream
07/14/1981US4278315 System for interconnection of multiple insulated wires
07/08/1981EP0031369A1 Dialing interval transmission gating arrangement.
07/07/1981US4277650 Single frequency tone receiver
06/1981
06/30/1981US4276639 Telephone exchange with time shared speech paths and selectively attenuated speech signals
06/30/1981CA1104217A1 Coded multifrequency digital signal receiver
06/16/1981US4273966 Terminal apparatus for telecommunications lines
06/16/1981US4273965 Tone decoding circuit
06/11/1981WO1981001623A1 Programmable multifrequency tone receiver
06/09/1981US4272648 Gain control apparatus for digital telephone line circuits
06/09/1981CA1102919A1 Digital tone decoder system
06/09/1981CA1102887A1 Multifrequency signal receiver
05/1981
05/13/1981EP0028404A1 Receiver for push-button PCM-encoded multifrequency signals
05/06/1981EP0028104A1 Signal control system for a time-division speech network
05/05/1981US4266099 Pulse rejection and duration correction circuit
05/05/1981CA1100641A1 Multifrequency signal receiving system
04/1981
04/14/1981US4262173 Connecting blocks for telephone systems
04/14/1981CA1099345A1 Tone signal detector
04/08/1981EP0026413A1 Circuit arrangement for registering the switching state in a circuit especially constituted by subscriber lines in telephone exchanges
04/08/1981EP0026412A1 Circuit arrangement to avoid the adverse effect of the share of alternating tension during the registration of the switching state in a circuit especially constituted by subscriber lines in telephone exchanges
04/07/1981US4260856 Distributor
04/02/1981WO1981000946A1 Terminal apparatus for telecommunications lines
04/01/1981EP0025947A1 Electric distribution busbar
03/1981
03/25/1981EP0025729A1 Switch with several crosspoint layers
03/24/1981CA1098008A1 Post wire guide latching means
03/19/1981WO1981000800A1 Improved binary detecting and threshold circuit
03/17/1981CA1097753A1 Pulse controlled switching circuits
03/10/1981US4255623 Apparatus for pulse train measurement
03/10/1981CA1097415A1 Matrix terminal block
03/03/1981US4254305 Current limited subscriber line feed circuit
02/1981
02/17/1981CA1096076A1 Dtmf and rotary dial signal receiver
02/11/1981EP0023689A1 Logic apparatus for the preprocessing of alarm signals
01/1981
01/22/1981WO1981000183A1 Dialing interval transmission gating arrangement
01/20/1981CA1094150A1 Line protector for a communications circuit
01/13/1981US4245325 Digital multifrequency signalling receiver
12/1980
12/30/1980US4242721 Electrical connector assembly for interconnecting remote signal stations to central signal processing systems
12/30/1980CA1092721A1 Wiring substrate for a matrix circuit
12/30/1980CA1092665A1 Multi-frequency signal receiver
12/16/1980CA1091834A1 Electric network for use in a subscriber's loop
12/16/1980CA1091796A1 Modular termination system for telecommunication devices
12/02/1980US4237346 Bridge lifter module
12/02/1980CA1090928A1 Dual mode telephone subscriber loop current detector
11/1980
11/12/1980EP0018697A1 Digital frequency detector for detecting one or more of a plurality of fixed frequencies in an analog signal
11/04/1980CA1089133A1 Telephone subscriber line circuit
10/1980
10/29/1980EP0017764A1 Subscriber line circuit with ground key activation indication, high ohmic commutable feeding and apparatus for ringing-signal generation
10/29/1980EP0017763A1 Subscriber line circuit with ground key activation indication and insulation fault indication
10/28/1980US4231018 Tone signal detector
10/28/1980US4230912 Dial pulse sensor and repeater circuit
10/28/1980US4230908 Telephone summing circuit
10/28/1980CA1088686A1 Tone applying line circuit
10/28/1980CA1088638A1 Frequency selective detector circuit
10/07/1980US4227248 PCM Tone signal generator
10/07/1980US4227055 Multifrequency receiver
10/07/1980US4227054 Digital constant-percent break pulse corrector
10/01/1980EP0016692A1 Frequency comparing circuit and selective calling device comprising such a circuit
09/1980
09/16/1980US4223185 Multifrequency digital signal receiver
09/16/1980US4223184 Minimum break/make pulse corrector
09/09/1980US4221936 Loop to ground start circuit
09/09/1980CA1085498A1 Multi-frequency code signaling between registers
09/02/1980US4220834 Telephone line attenuator network and attenuator pad therefor
09/02/1980CA1085075A1 Multy-party telephone system
09/02/1980CA1085074A1 Solid state pulsing apparatus for pulsing selected line relay terminals
08/1980
08/26/1980US4219699 Telephone supervision system using DTMF signals
08/20/1980EP0014328A1 Busy-circuit for the "incoming" c-conductor in a telecommunication device
08/19/1980US4218589 Method and apparatus for testing tone generators
08/19/1980CA1084126A1 High-speed tone decoder utilizing a phase-locked loop
08/12/1980US4217023 Device for connecting racks to distribution frames in telecommunications exchanges
08/05/1980US4216463 Programmable digital tone detector
08/05/1980CA1083256A1 Telephone exchange apparatus
07/1980
07/15/1980US4213013 Telephone network/subscriber interface device
07/15/1980US4212507 Selective interconnection system and connector
07/08/1980US4211897 Multifrequency signal receiving system
07/01/1980US4210375 Connecting unit for dispatchers systems
06/1980
06/17/1980CA1079882A1 Pulse counting circuit for key telephone system
06/10/1980US4207436 Constant percent break type dial pulse corrector
06/10/1980CA1079388A1 Method and trunk line network between units
06/10/1980CA1079368A1 Tone detection synchronizer
06/03/1980US4206323 Dual tone multifrequency signal receiver
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