FR10892E
(en )
1909-10-21
Device for automatically establishing communication between two subscribers of a telephone network at the central office
FR349757A
(en )
1905-06-12
Device for automatically establishing communication between two subscribers of a telephone network at the central office
FR5515E
(en )
1906-05-02
Device for automatically establishing, at the central office, communication between two subscribers of a telephone network
CH51869A
(en )
1911-10-16
Installation to automatically establish communication between two subscribers of a telephone network at the central office
CH41063A
(en )
1908-09-16
Installation to automatically establish communication between two subscribers of a telephone network at the central office
CH36229A
(en )
1906-12-31
Installation to automatically establish communication between two subscribers of a telephone network at the central office
CH33515A
(en )
1905-12-31
Installation to automatically establish communication between two subscribers of a telephone network at the central office
FR468891A
(en )
1914-07-18
Device for telephones preventing a third party from listening to the conversation between two extensions
US391762A
(en )
1888-10-23
Telephone-exchange system
ES48874A1
(en )
1910-11-16
A new device called "Telephone".
FR470235A
(en )
1914-08-28
Recorder for telephone network
FR395727A
(en )
1909-03-16
Automatic telephone intercom system
FR426643A
(en )
1911-07-11
Device for telephoning, telegraphing or signaling by using the same network for the transmission or distribution of electric energy
FR476042A
(en )
1915-07-07
Improvements in establishing telephone communications between the automatic network and a manual line
US629163A
(en )
1899-07-18
Telephone system.
FR445590A
(en )
1912-11-14
Subscriber station for automatic telephone systems
FR481822A
(en )
1917-01-23
Improvement in the equipment of an automatic telephone network
DE69219639D1
(en )
1997-06-19
Device and method for establishing a connection between ISDN data devices and the data devices connected to a telephone switched network
FR436734A
(en )
1912-04-03
Call device for telephone systems
FR452368A
(en )
1913-05-15
Telephone network system
FR454319A
(en )
1913-07-01
Automatic call device for multiple phone calls
FR1034629A
(en )
1953-07-28
Improvements to signaling systems used to characterize subscriber lines in a telephone network
FR476040A
(en )
1915-07-07
New call device for automatic telephony
CH10532A
(en )
1896-01-31
PBX allowing telephone communications between subscribers of a network, without the intermediary of special employees
CH51546A
(en )
1911-09-01
Telephone booth