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

Telephonic communications – Substation or terminal circuitry – Visual signalling

Communication apparatus

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

Communication device comprising an off-hook detection circuit

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

Communication interface having combined shaping of receive...

Telephonic communications – Substation or terminal circuitry – Hold circuit

Communication system, exchange and communication holding...

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

Communication terminal apparatus

Telephonic communications – Substation or terminal circuitry

Communication terminal device adapted to physical...

Telephonic communications – Substation or terminal circuitry

Communication terminal provided for a user selected...

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Communication terminals with a dual use speaker for sensing...

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

Compatibility circuit for telephone headset

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

Computer telephony headset amplifier

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Conference telephone system and method

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Conference telephone using dynamic modeled line hybrid

Telephonic communications – Substation or terminal circuitry – Wire distribution

Connecting device for connecting sheathed lines for telephones a

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

Connection apparatus for connecting a digital or analog...

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

Connection apparatus for connecting a digital or analog...

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Control circuit for mobile telephone with full duplex operation

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Control circuit having a direct current control loop for control

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Control device for a hand-free alternate operating telephone set

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

Control device for a hands-free telephone set