IT1135211B - Inductive coupler for MODEM used with telephone - Google Patents
Inductive coupler for MODEM used with telephoneInfo
- 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
Links
- 230000001939 inductive effect Effects 0.000 title 1
- 230000008878 coupling Effects 0.000 abstract 2
- 238000010168 coupling process Methods 0.000 abstract 2
- 238000005859 coupling reaction Methods 0.000 abstract 2
- 230000005540 biological transmission Effects 0.000 abstract 1
Landscapes
- 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.
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) |
-
1981
- 1981-01-28 IT IT19378/81A patent/IT1135211B/en active
Also Published As
Publication number | Publication date |
---|---|
IT8119378A0 (en) | 1981-01-28 |
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