IT1226171B - Duplex amplifier for intercom - Google Patents

Duplex amplifier for intercom

Info

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
Application number
IT8112422A
Other languages
Italian (it)
Other versions
IT8112422A0 (en
Inventor
Brosow Jorgen
Original Assignee
Dasy Int Sa
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
Priority claimed from PCT/EP1980/000105 external-priority patent/WO1981000943A1/en
Application filed by Dasy Int Sa filed Critical Dasy Int Sa
Publication of IT8112422A0 publication Critical patent/IT8112422A0/en
Application granted granted Critical
Publication of IT1226171B publication Critical patent/IT1226171B/en

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.
IT8112422A 1980-09-26 1981-01-23 Duplex amplifier for intercom IT1226171B (en)

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)

Also Published As

Publication number Publication date
IT8112422A0 (en) 1981-01-23

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