LandOfFree - US Patents - Listing for Telephonic communications,Substation or terminal circuitry

Telephonic communications – Substation or terminal circuitry – Wire distribution

Data and voice transmission using composite cables and punch-dow

Telephonic communications – Substation or terminal circuitry – Impedance matching or line equalizing

Data signal attenuator and systems and methods for using same

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Detection of the speech activity of a source

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Device and method for automatically controlling sound volume in

Telephonic communications – Substation or terminal circuitry – Hold circuit

Device for adding intercom functions to a phone system

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Device for forming the hands-free function in a telephone set, a

Telephonic communications – Substation or terminal circuitry – Conversion of signal form

Dial tone annunciating system and method

Telephonic communications – Substation or terminal circuitry – Sidetone control or hybrid circuit

Differential receive booster amplifier for telephone instruments

Telephonic communications – Substation or terminal circuitry – Hold circuit

Digital access arrangement circuitry and method for...

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Digital adaptive filter and acoustic echo canceller using...

Telephonic communications – Substation or terminal circuitry

Digital communication system

Telephonic communications – Substation or terminal circuitry – Visual signalling

Digital communication system with transmission servers

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Digital loudspeaking telephone

Telephonic communications – Substation or terminal circuitry

Digital portable telephone set

Telephonic communications – Substation or terminal circuitry – Amplifying

Digital sound level control apparatus

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Digital subscriber line (DSL) modem compatible with home...

Telephonic communications – Substation or terminal circuitry – Conversion of signal form

Digital telephone control interface system

Telephonic communications – Substation or terminal circuitry – Conversion of signal form

Digital telephone set capable of being simultaneously used by a

Telephonic communications – Substation or terminal circuitry – Conversion of signal form

Digital telephone system with terminals connected to a digital e