IT1135211B - Inductive coupler for MODEM used with telephone - Google Patents

Inductive coupler for MODEM used with telephone

Info

Publication number
IT1135211B
IT1135211B IT19378/81A IT1937881A IT1135211B IT 1135211 B IT1135211 B IT 1135211B IT 19378/81 A IT19378/81 A IT 19378/81A IT 1937881 A IT1937881 A IT 1937881A IT 1135211 B IT1135211 B IT 1135211B
Authority
IT
Italy
Prior art keywords
modem
sensor
amplifier
telephone
linear current
Prior art date
Application number
IT19378/81A
Other languages
Italian (it)
Other versions
IT8119378A0 (en
Inventor
Antonio Gray
Original Assignee
Cise Spa
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cise Spa filed Critical Cise Spa
Priority to IT19378/81A priority Critical patent/IT1135211B/en
Publication of IT8119378A0 publication Critical patent/IT8119378A0/en
Priority to EP81201165A priority patent/EP0050899A1/en
Priority to US06/315,075 priority patent/US4415769A/en
Application granted granted Critical
Publication of IT1135211B publication Critical patent/IT1135211B/en

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  • Devices For Supply Of Signal Current (AREA)

Abstract

The input from the MODEM is fed to a linear current amplifier (22) whose output drives a coil (23) arranged close to the telephone line transformer (11). Another coil (24) acts as a sensor for signals in the transformer and feeds a second linear current amplifier (25). The amplified signal is filtered (26) to reduce its noise component before being output to the MODEM. A cut-off device (28) is in series with the sensor (24) and its amplifier (25), to block reception when a signal is bent sent by the MODEM. An electronic switch may be used or, alternatively, the gain of the sensor amplifier may be reduced. The coupling device may be in the form of a baseplate on which the telephone stands, and/or coupling may be to the handset transducers. Distortions inherent in acoustic couplers are avoided, including those limiting transmission rate.
IT19378/81A 1980-10-27 1981-01-28 Inductive coupler for MODEM used with telephone IT1135211B (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
IT19378/81A IT1135211B (en) 1981-01-28 1981-01-28 Inductive coupler for MODEM used with telephone
EP81201165A EP0050899A1 (en) 1980-10-27 1981-10-22 Device for the transmission and receipt of signals through a telephone line
US06/315,075 US4415769A (en) 1980-10-27 1981-10-26 Electromagnetic telephone coupling device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT19378/81A IT1135211B (en) 1981-01-28 1981-01-28 Inductive coupler for MODEM used with telephone

Publications (2)

Publication Number Publication Date
IT8119378A0 IT8119378A0 (en) 1981-01-28
IT1135211B true IT1135211B (en) 1986-08-20

Family

ID=11157184

Family Applications (1)

Application Number Title Priority Date Filing Date
IT19378/81A IT1135211B (en) 1980-10-27 1981-01-28 Inductive coupler for MODEM used with telephone

Country Status (1)

Country Link
IT (1) IT1135211B (en)

Also Published As

Publication number Publication date
IT8119378A0 (en) 1981-01-28

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