IT1226171B - Duplex amplifier for intercom - Google Patents
Duplex amplifier for intercomInfo
- Publication number
- IT1226171B IT1226171B IT8112422A IT1242281A IT1226171B IT 1226171 B IT1226171 B IT 1226171B IT 8112422 A IT8112422 A IT 8112422A IT 1242281 A IT1242281 A IT 1242281A IT 1226171 B IT1226171 B IT 1226171B
- Authority
- IT
- Italy
- Prior art keywords
- channel
- receive
- amplitude
- open
- amplifier
- Prior art date
Links
Landscapes
- Interconnected Communication Systems, Intercoms, And Interphones (AREA)
Abstract
The output (R,F) of the telephone line (KL,a,b) is connected to a point (P,G) at the input of the receive channel. This is accomplished via a resistance network (R15-R21) with whose help the amplitude of the signal coming from the transmit channel can be made equal to the amplitude of the signal entering the receive channel. Coincident signals cancel whilst noncoincident wanted signals can be processed. The receive and transmit channels are open in the quiescent state and attenuated in the low frequency band of the transmission waveband. This attenuation is eliminated when the channel concerned is in operation.. The amplifier is open in both transmission directions for most of the time and the duplex mode only interrupted briefly in especially adverse conditions.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/EP1980/000105 WO1981000943A1 (en) | 1979-09-26 | 1980-09-26 | Duplex amplifyer particularly for interphone |
Publications (2)
Publication Number | Publication Date |
---|---|
IT8112422A0 IT8112422A0 (en) | 1981-01-23 |
IT1226171B true IT1226171B (en) | 1990-12-20 |
Family
ID=8164809
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IT8112422A IT1226171B (en) | 1980-09-26 | 1981-01-23 | Duplex amplifier for intercom |
Country Status (1)
Country | Link |
---|---|
IT (1) | IT1226171B (en) |
-
1981
- 1981-01-23 IT IT8112422A patent/IT1226171B/en active
Also Published As
Publication number | Publication date |
---|---|
IT8112422A0 (en) | 1981-01-23 |
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