SE7807783L - ELECTRONIC CIRCUIT IN A TELEPHONE SWITCH FOR POWER SUPPLY OF TELEPHONE CIRCUITS - Google Patents

ELECTRONIC CIRCUIT IN A TELEPHONE SWITCH FOR POWER SUPPLY OF TELEPHONE CIRCUITS

Info

Publication number
SE7807783L
SE7807783L SE7807783A SE7807783A SE7807783L SE 7807783 L SE7807783 L SE 7807783L SE 7807783 A SE7807783 A SE 7807783A SE 7807783 A SE7807783 A SE 7807783A SE 7807783 L SE7807783 L SE 7807783L
Authority
SE
Sweden
Prior art keywords
line
telephone
power supply
electronic circuit
senses
Prior art date
Application number
SE7807783A
Other languages
Swedish (sv)
Other versions
SE420039B (en
Inventor
L Hammarberg
Original Assignee
Ellemtel Utvecklings Ab
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 Ellemtel Utvecklings Ab filed Critical Ellemtel Utvecklings Ab
Priority to SE7807783A priority Critical patent/SE420039B/en
Publication of SE7807783L publication Critical patent/SE7807783L/en
Publication of SE420039B publication Critical patent/SE420039B/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems

Abstract

An electric circuit arrangement which is part of a telephone exchange and is connected to a power source for supplying current to the telephone sets connected to the exchange. The circuit arrangement contains two differential amplifiers OP1, OP2, one of which OP1 senses the feed current I to the line by detecting the voltage drop across a resistance r, directly connected to the line. The second differential amplifier OP2 senses any voltage changes across the line Le and sends a control quantity to an emitter sensor T connected in series between the power source so that the line current changes in dependence on the voltage change across the line. The circuit thus acts as a simulated impedance for the transverse line signals. <IMAGE>
SE7807783A 1978-07-13 1978-07-13 Electronic circuit arrangement in a telephone exchange for current supply SE420039B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
SE7807783A SE420039B (en) 1978-07-13 1978-07-13 Electronic circuit arrangement in a telephone exchange for current supply

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE7807783A SE420039B (en) 1978-07-13 1978-07-13 Electronic circuit arrangement in a telephone exchange for current supply

Publications (2)

Publication Number Publication Date
SE7807783L true SE7807783L (en) 1980-01-14
SE420039B SE420039B (en) 1981-09-07

Family

ID=20335439

Family Applications (1)

Application Number Title Priority Date Filing Date
SE7807783A SE420039B (en) 1978-07-13 1978-07-13 Electronic circuit arrangement in a telephone exchange for current supply

Country Status (1)

Country Link
SE (1) SE420039B (en)

Also Published As

Publication number Publication date
SE420039B (en) 1981-09-07

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