| Patents for H04M 1 - Substation equipment, e.g. for use by subscribers (168,223) |
|---|
| 05/29/1979 | US4156797 Filter for voice operated triggering circuits |
| 05/29/1979 | CA1055461A1 Communication units |
| 05/22/1979 | US4156115 Apparatus and method for a multiple tone code sender system for automatic call initiation |
| 05/22/1979 | CA1055177A1 Telephone speech network |
| 05/22/1979 | CA1055176A1 Sound recording and reproducing machines |
| 05/22/1979 | CA1055175A1 Line card circuit for key telephone system |
| 05/17/1979 | WO1979000253A1 Communication system conferencing arrangement |
| 05/15/1979 | US4154990 Telephone set base member with bean bag attachment |
| 05/15/1979 | CA1054739A1 Telephone handset |
| 05/08/1979 | US4153823 Telephone lock |
| 05/08/1979 | US4153822 Telephone set |
| 05/08/1979 | CA1054278A1 Control unit mounting and interconnecting apparatus for telephone sets |
| 05/03/1979 | WO1979000227A1 Fastening arrangement in a telephone instrument |
| 05/03/1979 | WO1979000226A1 Driving method for a recording tape and apparatus for a telephone answering system |
| 05/01/1979 | US4152555 Artificial ear for telephonometric measurements |
| 05/01/1979 | US4152554 Hookswitch mechanism for telephone handset |
| 05/01/1979 | US4152553 Protective helmet with voice communication system |
| 05/01/1979 | US4152549 Suppressor of spurious ringing currents for telephone apparatus |
| 05/01/1979 | CA1053821A1 Receiver/sender for signalling between telephone switching facilities |
| 05/01/1979 | CA1053782A1 Telephone line transfer circuit |
| 04/24/1979 | US4151380 Post mounted public telephone |
| 04/24/1979 | US4151376 Amplifier for telephone handset |
| 04/24/1979 | CA1053391A1 Toll restricting method and apparatus |
| 04/17/1979 | US4150405 Remote control device for automatic telephone answering system |
| 04/17/1979 | US4150262 Piezoelectric bone conductive in ear voice sounds transmitting and receiving apparatus |
| 04/17/1979 | US4150259 Communication system conferencing arrangement |
| 04/17/1979 | CA1052923A1 Telephone pushbutton dial assembly |
| 04/10/1979 | US4149033 Acoustic coupler assembly |
| 04/03/1979 | US4147903 Telephone guard |
| 03/27/1979 | US4146753 Transmit/receive network for telephone-subscriber station |
| 03/27/1979 | US4146292 Telephone wall mounting |
| 03/27/1979 | US4146191 Microphone retriever |
| 03/27/1979 | CA1051352A1 Acoustical communications headset |
| 03/20/1979 | US4145583 Removable microphone hangup adapter |
| 03/20/1979 | US4145581 Automatic telephone dialer for use in intrusion detection systems |
| 03/13/1979 | US4144413 Rotary telephone dial |
| 03/06/1979 | US4143287 Photo coupling line isolation circuit |
| 03/06/1979 | US4143247 Automatic signal level adjusting circuits for use in telephone sets |
| 03/06/1979 | US4143243 Telephone system |
| 03/06/1979 | US4142312 Station set for mobile radiotelephone units |
| 03/06/1979 | CA1050154A1 Telephone conferencing apparatus |
| 02/27/1979 | US4142184 Digital multitone generator for telephone dialing |
| 02/27/1979 | CA1049670A1 Multitone pushbutton dial phase shift scanning circuitry |
| 02/20/1979 | US4140881 Telephone loop extending apparatus |
| 02/20/1979 | CA1049170A1 Signalling device for key telephone systems |
| 02/20/1979 | CA1049135A1 Communications headset with rotatable and tiltable electrical connector |
| 02/13/1979 | US4139744 Reversible hand-held microphone |
| 02/13/1979 | US4139743 Headset |
| 02/13/1979 | US4139741 Phone guard for locking out long-distance calls |
| 02/13/1979 | CA1048669A1 Subscriber loop verification device and method |
| 02/06/1979 | US4138598 Headset construction |
| 02/06/1979 | CA1048184A1 Pulse duration correction circuit |
| 01/23/1979 | US4136266 Telephone intruder alert system |
| 01/23/1979 | CA1047182A1 Push button telephone attachment |
| 01/16/1979 | US4135058 Dual tape transport system with related method and means for reducing cueing time |
| 01/16/1979 | CA1046672A2 Automatic dialer accessory for a conventional telephone |
| 01/16/1979 | CA1046671A1 Automatic dialer accessory for a conventional telephone |
| 01/09/1979 | US4134141 Recording and reproducing means |
| 01/09/1979 | US4134032 Audio signal discriminator circuit |
| 01/09/1979 | US4133983 Electronic network for telephone set |
| 01/02/1979 | US4132871 Digitally synthesized multi-frequency signal generator |
| 01/02/1979 | US4132863 Automatic gain and return loss compensating line circuit |
| 01/02/1979 | US4132861 Headset having double-coil earphone |
| 01/02/1979 | CA1045734A2 Digital echo suppressor |
| 01/02/1979 | CA1045733A1 Tone receiver |
| 01/02/1979 | CA1045715A1 Recording and/or reproducing apparatus |
| 12/26/1978 | US4131769 Telephone lock |
| 12/26/1978 | US4131768 Telephone switch control clip |
| 12/19/1978 | US4130743 Terminal equipment for a multiplex carrier current telephone system |
| 12/19/1978 | US4130742 Switch actuator for one-piece telephone |
| 12/19/1978 | US4130740 Telephone handset with rotatably locking receiver |
| 12/19/1978 | US4130738 Bidirectional data transfer and storage system |
| 12/19/1978 | US4130731 Portable telephone system |
| 12/19/1978 | US4130728 Combined mounting for through-the-wall viewer and intercom |
| 12/19/1978 | CA1044831A1 Tape monitoring and control for centrally located automatic answering and recording equipment |
| 12/19/1978 | CA1044830A1 Centrally located automatic answering and recording equipment |
| 12/19/1978 | CA1044803A1 Remote control transcribing device |
| 12/12/1978 | CA1044389A1 Key telephone privacy circuit |
| 12/12/1978 | CA1044314A1 Coupling circuit for providing bilateral protection from hazardous voltages |
| 11/21/1978 | US4126768 Portable automatic number outpulser |
| 11/21/1978 | US4126763 Control circuit for a remote controlled telephone answering device |
| 11/14/1978 | US4125872 Multiline automatic calling system adapter |
| 11/07/1978 | US4124785 Telephone set |
| 11/07/1978 | US4124781 Telephone toll restrictor |
| 11/07/1978 | US4124773 Audio storage and distribution system |
| 10/31/1978 | CA1041684A1 Telephone line amplifier with selective gain |
| 10/24/1978 | US4122308 Telephone call metering device |
| 10/24/1978 | US4122307 Telephone voice frequency response system for message recording |
| 10/24/1978 | US4122306 Telephone answering apparatus providing selective message communication |
| 10/24/1978 | US4122304 Control circuitry for a radio telephone |
| 10/17/1978 | US4121061 Telephone holder |
| 10/17/1978 | US4121052 Telephone data recording system |
| 10/17/1978 | US4120107 Telephone bracket for holding advertising and writing instrument |
| 10/17/1978 | CA1040769A1 Telephone answering system with remote playback |
| 10/10/1978 | US4119810 Pushbutton telephone apparatus with automatic dialing and combinational sequential control signalling capabilities |
| 10/10/1978 | US4119809 Braille lens for telephone dials |
| 10/10/1978 | US4119801 Mode switching and voltage regulator circuitry for a telephone answering device |
| 10/10/1978 | US4119800 Radio-telephone interconnection system |
| 10/10/1978 | CA1040327A1 Active hybrid sidetone producing circuitry for sidetoneless telephone |
| 10/03/1978 | US4118606 Acoustical voice transmitting headset |