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
Links
Landscapes
- 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.
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) |
-
1977
- 1977-09-23 IT IT2786077A patent/IT1114420B/en active
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
TA | Fee payment date (situation as of event date), data collected since 19931001 |
Effective date: 19960928 |