GB533618A - Improvements in telephone systems - Google Patents

Improvements in telephone systems

Info

Publication number
GB533618A
GB533618A GB29021/39A GB2902139A GB533618A GB 533618 A GB533618 A GB 533618A GB 29021/39 A GB29021/39 A GB 29021/39A GB 2902139 A GB2902139 A GB 2902139A GB 533618 A GB533618 A GB 533618A
Authority
GB
United Kingdom
Prior art keywords
line
loud
equipment
impedance
coil
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
GB29021/39A
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.)
General Electric Co PLC
Original Assignee
General Electric Co PLC
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 General Electric Co PLC filed Critical General Electric Co PLC
Priority to GB29021/39A priority Critical patent/GB533618A/en
Priority to US360099A priority patent/US2301530A/en
Publication of GB533618A publication Critical patent/GB533618A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/001—Two-way communication systems between a limited number of parties

Abstract

533,618. Thermionic valve circuits. GENERAL ELECTRIC CO., Ltd., and FAIRBAIRN, E. P. Oct. 31, 1939, No. 29021. [Class 40 (v)] [Also in Group XXXIXI] In a system in which some substations have loud-speaking equipment and others ordinary equipment, balanced conditions in the various connections are obtained by associating a compensating network with the loud-speaking equipment in order that its impedance characteristic may resemble that of an ordinary equipment. As shown, the transmitter and receiver of the loudspeaking set are connected over 1A-1D to a hybrid coil having line windings LW1, LW2 connected to the line over a compensating network of resistances R1-R4, capacity C1 and an aircored inductance AC1. The balance network R5-R7, C2, AC2, LA connected to coil windings LB1, LB2, simulates the impedance of the line as seen from the terminals of LW1, LW2. The line is looped over coil H and the input of the loud-speaker amplifier is shunted by resistance R9 if its impedance is high.
GB29021/39A 1939-10-31 1939-10-31 Improvements in telephone systems Expired GB533618A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB29021/39A GB533618A (en) 1939-10-31 1939-10-31 Improvements in telephone systems
US360099A US2301530A (en) 1939-10-31 1940-10-07 Telephone system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB29021/39A GB533618A (en) 1939-10-31 1939-10-31 Improvements in telephone systems

Publications (1)

Publication Number Publication Date
GB533618A true GB533618A (en) 1941-02-17

Family

ID=10284976

Family Applications (1)

Application Number Title Priority Date Filing Date
GB29021/39A Expired GB533618A (en) 1939-10-31 1939-10-31 Improvements in telephone systems

Country Status (2)

Country Link
US (1) US2301530A (en)
GB (1) GB533618A (en)

Also Published As

Publication number Publication date
US2301530A (en) 1942-11-10

Similar Documents

Publication Publication Date Title
US2829203A (en) Electronic telephone subscriber's line circuit for neutralizing the effects of longitudinal induction and longitudinal unbalance
JPS598977B2 (en) Time-shared electronic telephone communication system
US2924667A (en) Reduction of transmission loss in bridged subscriber loops
GB533618A (en) Improvements in telephone systems
US2990457A (en) Tandem echo suppressor circuits
GB481085A (en) Improvements in or relating to two-wire-four-wire combinations in electric signalling systems
GB501915A (en) Telephone exchange systems
US1919314A (en) Telephone instrument circuit
US2775649A (en) Telephone subscriber sets
US2230360A (en) Multiway telephone circuit
US1665683A (en) Telephone system
US1907147A (en) Transmission circuits
Bell et al. Metallic polar-duplex telegraph system for long small-gage cables
US978083A (en) Telephone repeater system.
US1484396A (en) Telephone system
US2345046A (en) Intercommunicating system
US1551171A (en) Automatic telephone substation circuits
US1930537A (en) Substation telephone circuit
US3172959A (en) Telephone amplifier
US2257592A (en) Directional monitoring system
US1542524A (en) Apparatus for the electrical transmission of intelligence
US348512A (en) Telephone and telegraph circuit
GB706784A (en) Improvements in or relating to telephone subscriber sets
US1374219A (en) Composite transmission system
US2102735A (en) Carrier telegraph system