Patents
Sitemap › H04 - Electric communication technique › H04M - Telephonic communication › H04M 1 - Substation equipment, e.g. for use by subscribers
Patents for H04M 1 - Substation equipment, e.g. for use by subscribers (168,223)
12/1977
12/20/1977US4064366 Intrinsically safe telephone systems
12/20/1977US4064362 Hearing protector
12/13/1977US4063046 Telephone mounted calculator
12/13/1977US4062608 Telephone handset cord storage apparatus
12/06/1977US4061888 Control unit mounting and interconnecting apparatus for telephone sets
12/06/1977US4061887 Key telephone adapter for electronic telephone switching system
12/06/1977US4061886 Dual tone multiple frequency generator
12/06/1977US4061875 Audio processor for use in high noise environments
11/1977
11/22/1977US4059728 Touchpad dialer for mobile telephones
11/15/1977US4058805 Digital multitone generator for telephone dialing
11/15/1977US4058690 Transmitter cut-off device
11/15/1977US4058689 Variably adjustable shoulder telephone handset support
11/15/1977US4058686 Telephone attachment
11/15/1977US4058679 Telephone answering device without outgoing message tape
11/08/1977US4057697 Telephone dial lock
11/01/1977US4056696 Flat panel telephone station set
11/01/1977US4056692 Digital tone generator
11/01/1977US4056690 Automatic number identification in subscriber loop carrier systems
10/1977
10/11/1977US4053718 Automatic telephone call generator
10/04/1977US4052570 Telephone system
09/1977
09/27/1977US4051333 Tip and ring conductor voltage tester
09/20/1977US4049927 Telephone hand-set holding means
09/20/1977US4049925 Solenoid circuit for pushbutton release in telephones
09/20/1977US4049924 Pushbutton dials
09/20/1977US4049914 Frequency division multiplex voice communication apparatus with hierarchy of stations
09/13/1977US4048647 Solid state disconnect device
09/13/1977US4048453 Telephone handset support device
09/06/1977US4047241 Capacitive switch
09/06/1977US4046971 Switching arrangement for telephone subsets using impulse-type pushbutton calling
09/06/1977US4046965 Toll restrictor for a time division telecommunication system
08/1977
08/30/1977US4045619 Telephone control system
08/16/1977US4042793 Telephone mouthpiece keyboard
08/16/1977US4042792 Telephone subscriber's apparatus for signalling decimal digit values represented in printed form
08/09/1977US4041255 Switching circuit for telecommunications lines
08/09/1977US4041247 Method and apparatus for operation of carbon microphones at low average current levels
08/02/1977US4039768 Pay telephone station monitor system
08/02/1977US4039765 Headset with adjustable microphone support
08/02/1977US4039761 Electronic apparatus for the permanent storage and automatic dialing of telephone numbers
08/02/1977US4039760 Cordless telephone system
08/02/1977US4039759 Line security device
07/1977
07/19/1977US4037067 Anti-vandalism protective attachment device for a pay telephone
07/19/1977US4037063 Microphone holder assembly
07/19/1977US4037053 Automatic telephone answering apparatus
07/05/1977US4034167 Telephone switch retaining device
07/05/1977US4034163 Apparatus for mechanically operating push buttons
07/05/1977US4033651 Desk mounting for telephone
06/1977
06/28/1977US4032727 Releasably locked mounting assembly for telephone dials
06/28/1977US4032723 Cordless telephone system
06/28/1977US4032722 Telephone dialing arrangement for calling a single party
06/28/1977US4032718 Four-wire integrable hybrid
06/28/1977US4032713 Recording tape control arrangement for telephone answering apparatus
06/28/1977US4032712 Telephone answering device with separate announcement erase and playback control timing periods
06/21/1977US4031333 Circuit to indicate the simultaneous off-hook condition of at least two of a plurality of telephone subsets on the same telephone line
06/21/1977US4031331 Telephone speech network
06/21/1977US4031323 Remote controllable telephone answering device having a dual playback capability
06/14/1977US4029908 Repertory dialer logic
06/07/1977US4028628 Transceivers for single channel carrier telephone systems
06/07/1977US4028508 Telephone lock
06/07/1977US4028502 Apparatus for adapting multi-line telephone instrument for use by the blind
05/1977
05/31/1977US4027115 Electroacoustic sound generator
05/31/1977US4027109 Telephone call diverting system
05/31/1977US4027097 Split cover plate for telephone outlet
05/31/1977US4026033 Telephone handset indicia holder
05/24/1977US4025865 Frequency-signalling circuit for a telephone
05/24/1977US4025733 Pressure seal headband
05/24/1977US4025728 Speaker telephone
05/24/1977US4024661 Self-standing or phone mounted calendar
05/17/1977US4024348 Remote controllable automatic telephone answering apparatus
05/17/1977US4024347 Telephone calculator
05/17/1977US4024346 Telephone line amplifier
05/17/1977US4023209 Protective helmet assembly with segmental outer shell
05/10/1977US4022992 Phone guard for locking out long-distance calls
05/10/1977US4022985 Key telephone system with a common push-button sender system
05/03/1977US4021653 Digital programmable tone detector
05/03/1977US4020527 Grip for a hand held portable device
04/1977
04/26/1977US4020297 Adjustable headset
04/26/1977US4020295 Rotary dial restriction circuit
04/19/1977US4018998 Communication hand-set foldable for protection
04/19/1977US4018997 Pluggable key set telephone cross connect device
04/12/1977USRE29183 Telephone range expander
04/12/1977US4017693 Synthesizer of multifrequency code signals
04/12/1977US4017692 Telephone call-diverter system
04/12/1977US4017686 Telephone line voltage actuated switches
04/05/1977US4016556 Optically encoded acoustic to digital transducer
03/1977
03/29/1977US4015090 Recording and/or reproducing apparatus
03/22/1977US4013971 Integrated amplifier
03/15/1977US4012602 Toll restrictor for touch type digit selector
03/15/1977US4012601 Automatic pushbutton dial assembly for a subscriber telephone
03/15/1977US4012600 Automatic pushbutton dial system for a subscriber telephone
03/08/1977US4011414 Automatic dial system for a subscriber telephone
03/08/1977US4011413 Hold circuit for telephone
03/08/1977US4011411 Automatic telephone answering and recording device
03/01/1977US4010454 Magnetic bubble signal generator
03/01/1977US4010382 Push-button type pulse generating switch
03/01/1977US4010330 Automatic telephone dialer
02/1977
02/15/1977US4008380 Telephone conversion unit with multiple memory system
02/15/1977US4008379 Touch-pad to dial conversion unit
02/08/1977US4007459 Multitone pushbutton dial phase shift scanning circuitry
02/08/1977US4007333 Automatic call transmitter of the dual tone multifrequency type
02/01/1977US4006318 Inertial microphone system
1 ... 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683