IT1114420B - Telephone instrument transmit and receive circuit - uses amplifiers instead of induction coil located on diagonals of Wheatstone bridge network (NL 6.6.78) - Google Patents

Telephone instrument transmit and receive circuit - uses amplifiers instead of induction coil located on diagonals of Wheatstone bridge network (NL 6.6.78)

Info

Publication number
IT1114420B
IT1114420B IT2786077A IT2786077A IT1114420B IT 1114420 B IT1114420 B IT 1114420B IT 2786077 A IT2786077 A IT 2786077A IT 2786077 A IT2786077 A IT 2786077A IT 1114420 B IT1114420 B IT 1114420B
Authority
IT
Italy
Prior art keywords
diagonals
wheatstone bridge
induction coil
telephone instrument
bridge network
Prior art date
Application number
IT2786077A
Other languages
Italian (it)
Inventor
Arrigo Sebastiano D
Antonio Neri
Original Assignee
Cselt Centro Studi Lab Telecom
Ates Componenti Elettron
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 Cselt Centro Studi Lab Telecom, Ates Componenti Elettron filed Critical Cselt Centro Studi Lab Telecom
Priority to IT2786077A priority Critical patent/IT1114420B/en
Priority to GB47725/77A priority patent/GB1546046A/en
Priority to DE2753130A priority patent/DE2753130B2/en
Priority to BR7707915A priority patent/BR7707915A/en
Priority to US05/856,676 priority patent/US4146753A/en
Priority to NLAANVRAGE7713405,A priority patent/NL187662C/en
Priority to SE7713702A priority patent/SE440303B/en
Priority to FR7736279A priority patent/FR2373200A1/en
Priority to JP52145623A priority patent/JPS5816782B2/en
Application granted granted Critical
Publication of IT1114420B publication Critical patent/IT1114420B/en

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  • Amplifiers (AREA)

Abstract

The telephone instrument circuit replaces the usual ASTIC induction coil with a microphone transmit amplifier (AT) and a receiver amplifier (AR). Both amplifiers are placed on diagonals in a Wheatstone bridge network to prevent interaction. One arm of the Wheatstone bridge (Z3) is adjustable to balance the bridge with the subscriber line located in an opposite arm (Z4) of the bridge. Use of a transmit amplifier allows the carbon granule microphone to be replaced by dynamic and other inserts.
IT2786077A 1976-12-03 1977-09-23 Telephone instrument transmit and receive circuit - uses amplifiers instead of induction coil located on diagonals of Wheatstone bridge network (NL 6.6.78) IT1114420B (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
IT2786077A IT1114420B (en) 1977-09-23 1977-09-23 Telephone instrument transmit and receive circuit - uses amplifiers instead of induction coil located on diagonals of Wheatstone bridge network (NL 6.6.78)
GB47725/77A GB1546046A (en) 1976-12-03 1977-11-16 Transmitting and receiving circuit for subscriber telephone sets
DE2753130A DE2753130B2 (en) 1976-12-03 1977-11-29 Circuit for receiving and transmitting signals
BR7707915A BR7707915A (en) 1976-12-03 1977-11-29 CIRCUIT FOR RECEIVING AND TRANSMITTING SIGNS, ADAPTED TO BE INSERTED IN A USER'S TELEPHONE
US05/856,676 US4146753A (en) 1976-12-03 1977-12-01 Transmit/receive network for telephone-subscriber station
NLAANVRAGE7713405,A NL187662C (en) 1976-12-03 1977-12-02 SWITCHING FOR PAIRING A MICROPHONE AND TELEPHONE WITH A SUBSCRIBER LINE.
SE7713702A SE440303B (en) 1976-12-03 1977-12-02 SENDER AND RECEIVER CIRCUIT FOR SUBSCRIPTION PHONE DEVICES
FR7736279A FR2373200A1 (en) 1976-12-03 1977-12-02 CIRCUIT FOR RECEIVING AND SENDING SIGNALS IN A SUBSCRIBER'S TELEPHONE DEVICE
JP52145623A JPS5816782B2 (en) 1976-12-03 1977-12-03 Telephone transmitter/receiver circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT2786077A IT1114420B (en) 1977-09-23 1977-09-23 Telephone instrument transmit and receive circuit - uses amplifiers instead of induction coil located on diagonals of Wheatstone bridge network (NL 6.6.78)

Publications (1)

Publication Number Publication Date
IT1114420B true IT1114420B (en) 1986-01-27

Family

ID=11222478

Family Applications (1)

Application Number Title Priority Date Filing Date
IT2786077A IT1114420B (en) 1976-12-03 1977-09-23 Telephone instrument transmit and receive circuit - uses amplifiers instead of induction coil located on diagonals of Wheatstone bridge network (NL 6.6.78)

Country Status (1)

Country Link
IT (1) IT1114420B (en)

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Effective date: 19960928