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GB1531692A - Telecommunication substation - Google Patents

Telecommunication substation

Info

Publication number
GB1531692A
GB1531692A GB16210/77A GB1621077A GB1531692A GB 1531692 A GB1531692 A GB 1531692A GB 16210/77 A GB16210/77 A GB 16210/77A GB 1621077 A GB1621077 A GB 1621077A GB 1531692 A GB1531692 A GB 1531692A
Authority
GB
United Kingdom
Prior art keywords
line
current
substation
circuit
april
Prior art date
Legal status (The legal status 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 status listed.)
Expired
Application number
GB16210/77A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
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 International Standard Electric Corp filed Critical International Standard Electric Corp
Publication of GB1531692A publication Critical patent/GB1531692A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/6008—Substation equipment, e.g. for use by subscribers including speech amplifiers in the transmitter circuit
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/738—Interface circuits for coupling substations to external telephone lines
    • H04M1/76—Compensating for differences in line impedance

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)
  • Amplifiers (AREA)

Abstract

1531692 Substation apparatus INTERNATIONAL STANDARD ELECTRIC CORP 19 April 1977 [26 April 1976] 16210/77 Heading H4K A transmitter circuit Tr, for a telephone substation, comprises a microphone M connected in series with an amplifier T1, T2 and an equalizing circuit D1, R14 compensating for variations in the length of the subscriber's line L1, L2 by varying the gain of T1, T2, the equalizing circuit being connected in a potentiometer circuit R13, R14, D1, R15 which provides a feedback path between the output A and the input, base T2, of the amplifier. The transmitter is powered by the line via R2 and diode bridge D2-5 and is connected across an impedance bridge (Fig. 2, not shown) formed by Z2, Z5, Z3, Z6. A capacitor C12 compensates for the A.C. negative feedback effect. The D.C. current in D1, R14 varies in the same sense as the D.C. current in the line and the impedance of D1, R14 varies in an opposite sense with said line current.
GB16210/77A 1976-04-26 1977-04-19 Telecommunication substation Expired GB1531692A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
BE2054973A BE841105A (en) 1976-04-26 1976-04-26 TELECOMMUNICATION DEVICE

Publications (1)

Publication Number Publication Date
GB1531692A true GB1531692A (en) 1978-11-08

Family

ID=3865331

Family Applications (1)

Application Number Title Priority Date Filing Date
GB16210/77A Expired GB1531692A (en) 1976-04-26 1977-04-19 Telecommunication substation

Country Status (6)

Country Link
AU (1) AU507967B2 (en)
BE (1) BE841105A (en)
DE (1) DE2718009A1 (en)
FR (1) FR2350014A1 (en)
GB (1) GB1531692A (en)
ZA (1) ZA771950B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0102660A2 (en) * 1982-08-25 1984-03-14 Philips Electronics Uk Limited Telephone circuit

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1546046A (en) * 1976-12-03 1979-05-16 Cselt Centro Studi Lab Telecom Transmitting and receiving circuit for subscriber telephone sets
FR2575625B1 (en) * 1984-12-27 1987-01-30 Thomson Csf SUBSCRIBER TELEPHONE SET WITH LOUDSPEAKER LOUDSPEAKER WITH REDUCED GAIN IN THE EVENT OF INSUFFICIENT POWER SUPPLY

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2818470A (en) * 1956-03-29 1957-12-31 Bell Telephone Labor Inc Compensated transistor circuit
US3546395A (en) * 1968-01-15 1970-12-08 Bell Telephone Labor Inc Active telephone set speech network employing transistor feedback loop for sidetone balance and equalization
DE1762058B2 (en) * 1968-03-29 1970-12-03 Siemens AG, 1000 Berlin u. 8000 München Circuit arrangement for centrally fed subscriber stations with speech circuits containing a resistor bridge
JPS5211166B1 (en) * 1970-07-23 1977-03-29
BE792329A (en) * 1971-12-09 1973-06-06 Int Standard Electric Corp ELECTRONIC TRANSMISSION CIRCUIT FOR TELEPHONE STATION

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0102660A2 (en) * 1982-08-25 1984-03-14 Philips Electronics Uk Limited Telephone circuit
EP0102660A3 (en) * 1982-08-25 1985-12-27 Philips Electronic And Associated Industries Limited Telephone circuit

Also Published As

Publication number Publication date
AU2453677A (en) 1978-10-26
ZA771950B (en) 1978-04-26
AU507967B2 (en) 1980-03-06
FR2350014A1 (en) 1977-11-25
DE2718009A1 (en) 1977-11-10
BE841105A (en) 1976-10-26

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Legal Events

Date Code Title Description
PS Patent sealed
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee