| Patents for H04M 1 - Substation equipment, e.g. for use by subscribers (168,223) |
|---|
| 10/03/1978 | US4118602 Telephone answering device having simplified mechanical controls |
| 10/03/1978 | CA1039873A1 Amplifier circuit for increasing transmit and receive levels |
| 09/26/1978 | US4117542 Electronic pocket directory |
| 09/26/1978 | US4117276 Handset locking and release mechanism |
| 09/26/1978 | US4117274 Key telephone privacy circuit |
| 09/26/1978 | US4117272 Start circuit for telephone answering device |
| 09/26/1978 | US4117270 Telephone answering and call diverting system |
| 09/26/1978 | US4117266 Recorder actuator for communication lines |
| 09/26/1978 | CA1039360A1 Apparatus and method to test the condition of an electric service line and to determine the presence and/or removal of electrical equipment connected to the line |
| 09/19/1978 | US4115659 Electroacoustical telephone adapter |
| 09/19/1978 | CA1038980A1 Touch pad to dial conversion unit |
| 09/19/1978 | CA1038841A1 Light emitting diode indicator assembly for a multiple pushbutton array |
| 09/12/1978 | US4113995 Telephone cradle adapter |
| 09/12/1978 | US4113993 Automatic dialer having a recall memory |
| 09/12/1978 | US4113992 Automatic dialer for facsimile terminals and the like |
| 09/12/1978 | US4113991 Automatic dialer having a selective retry capability |
| 08/29/1978 | US4110583 Earphone construction |
| 08/29/1978 | US4110568 Dual tone multifrequency generator |
| 08/29/1978 | US4110567 Multi-frequency generator using digital technique |
| 08/29/1978 | US4110560 Communication apparatus |
| 08/29/1978 | CA1037628A1 Manually actuable repertory dialer |
| 08/29/1978 | CA1037627A1 Pushbutton dials |
| 08/29/1978 | CA1037626A1 Telephone answering system |
| 08/29/1978 | CA1037625A2 Transient controlled telephone line circuit |
| 08/22/1978 | US4109112 Telephone isolation device |
| 08/22/1978 | CA1037172A1 Telephone substation with line powered auxiliary services |
| 08/15/1978 | US4107481 Telephone instruments |
| 08/15/1978 | US4107477 Multi-subscriber telephone apparatus |
| 08/15/1978 | CA1036733A2 Station loop control arrangement for telephone switching system |
| 08/15/1978 | CA1036732A2 Station loop control arrangement for telephone switching system |
| 08/15/1978 | CA1036731A2 Station loop control arrangement for telephone switching system |
| 08/08/1978 | US4105866 Telephone answering machine busy signal detection devices with switching means |
| 08/01/1978 | US4104487 Telephone answering device with remote controlled playback |
| 08/01/1978 | US4104485 Telephone loud-speaker system |
| 07/25/1978 | US4103115 Memory tone dialer |
| 07/18/1978 | US4100653 Device for attaching a microphone-speaker to an article of clothing |
| 07/11/1978 | US4100379 Communication units |
| 07/04/1978 | US4099034 Fastening arrangement in a telephone instrument of the one-piece type |
| 07/04/1978 | US4099033 Telephone security device |
| 06/27/1978 | US4097691 Remote telephone coupler as for medical emergency data transmission |
| 06/20/1978 | US4096357 Toll-call restriction system |
| 06/13/1978 | US4095056 Toll restrictor access circuit |
| 05/30/1978 | USRE29655 Telephone answering device |
| 05/30/1978 | US4092502 Telephone attachment for plug-in headset capability |
| 05/30/1978 | US4092500 Device for selectively interrupting mechanical operation of a manually operated telephone |
| 05/30/1978 | US4092496 Variable impedance detecting circuit for a telephone line auxiliary device |
| 05/23/1978 | US4091244 Multiple contact switch |
| 05/16/1978 | US4090042 Acoustical communications headset |
| 05/16/1978 | US4090037 Telephone set |
| 05/09/1978 | US4088848 Holder for microphones and the like |
| 05/09/1978 | US4088844 Telephone station set interface circuit |
| 05/09/1978 | US4088837 Combination telephone and calculator with common keyboard having reversible indicia |
| 05/02/1978 | US4087659 Tamperproof handset for railroad applications |
| 05/02/1978 | US4087653 Sound attenuating earcup assembly provided with receivers and contact microphone |
| 05/02/1978 | US4087650 Column and lever construction for a charactered telephone |
| 05/02/1978 | US4087638 DTMF Communication system |
| 04/25/1978 | US4086445 Telephone handset transmitter with improved output response |
| 04/25/1978 | US4086443 Automatic dialer with a programmable pause |
| 04/25/1978 | US4086442 Repertory diallers |
| 04/25/1978 | US4086440 Telephone set with loop current interruption timing control |
| 04/04/1978 | US4082920 Telephone testing equipment |
| 04/04/1978 | US4082919 Interconnect control for automatically connecting a simplex or half-duplex radio network to a standard telephone system |
| 03/28/1978 | US4081630 Telephone disabling device |
| 03/28/1978 | US4081629 Snap-in bracket for mounting a telephone dial within a telephone housing |
| 03/28/1978 | US4081624 Key telephone intercom line system |
| 03/28/1978 | US4081623 Sight operated telephone and machine controller |
| 03/28/1978 | US4081620 Sidetone control circuit for a telephone set |
| 03/28/1978 | US4081619 Switching arrangement for telecommunication subscriber stations using key-operated selection units |
| 03/28/1978 | US4081618 Automatic telephone dialling apparatus |
| 03/14/1978 | US4079211 Protection device for a subscriber's telephone set |
| 03/14/1978 | US4079200 Apparatus for recording replies to pre-recorded messages |
| 03/14/1978 | US4079196 Telephone control apparatus |
| 03/07/1978 | US4078155 Telephone apparatus for use in a conference room |
| 02/21/1978 | US4075439 Method for providing temporary telephone service |
| 02/14/1978 | US4074081 Apparatus for detecting the level of direct current or voltage on a telephone line |
| 02/14/1978 | US4074078 Telephone privacy device |
| 02/14/1978 | US4074071 Automatic telephone answering device with paired transducers |
| 02/07/1978 | US4072824 Automatic dialer for paging system or the like |
| 01/31/1978 | US4071715 Push-button switch for a multifrequency dialling telephone set |
| 01/31/1978 | US4071713 Telephone speech network |
| 01/31/1978 | US4071699 Apparatus providing for the remote display of calling numbers in a telephone system |
| 01/31/1978 | US4071696 Telephone wall jack cover |
| 01/31/1978 | US4071040 Water-proof air-pressure equalizing valve |
| 01/24/1978 | US4070554 Digital testing and power control in a digital communication system |
| 01/24/1978 | US4070553 Personal audio listening system |
| 01/17/1978 | US4069397 Automatic telephone answering device |
| 01/17/1978 | US4069396 Power saving circuit for use with a converter circuit in a telephone switching installation |
| 01/10/1978 | US4068282 Protective device for low current transmission circuits |
| 01/10/1978 | US4068178 Variable frequency waveform synthesizer |
| 01/10/1978 | US4068102 Wall-stand for telephone sets of standing handset type |
| 01/10/1978 | US4068095 Portable terminal with self-contained collapsible stand |
| 01/10/1978 | US4068092 Voice control circuit |
| 01/03/1978 | US4066848 Telephone ring detector circuit |
| 01/03/1978 | US4066842 Method and apparatus for cancelling room reverberation and noise pickup |
| 12/27/1977 | US4065755 Touch-Tone encoder unit for mobile radio transmitter |
| 12/27/1977 | US4065646 Power converter |
| 12/27/1977 | US4065642 Message signaling and alerting system and method thereof |
| 12/27/1977 | US4065362 Purification of organic isocyanates |
| 12/20/1977 | USRE29499 On premise telephone loop tester |
| 12/20/1977 | US4064377 Electronic hybrid and hybrid repeater |