GB583277A - Improvements in electrical signalling systems - Google Patents

Improvements in electrical signalling systems

Info

Publication number
GB583277A
GB583277A GB1925244A GB1925244A GB583277A GB 583277 A GB583277 A GB 583277A GB 1925244 A GB1925244 A GB 1925244A GB 1925244 A GB1925244 A GB 1925244A GB 583277 A GB583277 A GB 583277A
Authority
GB
United Kingdom
Prior art keywords
telephone
series
wires
direct
group xxxviii
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
GB1925244A
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.)
Automatic Telephone and Electric Co Ltd
Original Assignee
Automatic Telephone and Electric Co Ltd
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 Automatic Telephone and Electric Co Ltd filed Critical Automatic Telephone and Electric Co Ltd
Priority to GB1925244A priority Critical patent/GB583277A/en
Publication of GB583277A publication Critical patent/GB583277A/en
Expired legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B19/00—Mining-hoist operation
    • B66B19/06—Applications of signalling devices

Landscapes

  • Suspension Of Electric Lines Or Cables (AREA)

Abstract

583,277. Direct call systems. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd., PREIST, T. P., and WEBB, W. G. Oct. 7, 1944, No. 19252. [Class 40 (iv)] [Also in Group XXXVIII] Telephone facilities are provided over the direct-current signalling wires of a mine haulage system (see Group XXXVIII) by the use of telephone instruments T1, T2 of the standard magneto or sound powered type connected in series with isolating capacitors QA, QB across the two wires at the signalling point and engine house. A dry plate rectifier MRA is placed in series with the signal responding relay A to prevent its operation by ringing current.
GB1925244A 1944-10-07 1944-10-07 Improvements in electrical signalling systems Expired GB583277A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1925244A GB583277A (en) 1944-10-07 1944-10-07 Improvements in electrical signalling systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1925244A GB583277A (en) 1944-10-07 1944-10-07 Improvements in electrical signalling systems

Publications (1)

Publication Number Publication Date
GB583277A true GB583277A (en) 1946-12-13

Family

ID=10126265

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1925244A Expired GB583277A (en) 1944-10-07 1944-10-07 Improvements in electrical signalling systems

Country Status (1)

Country Link
GB (1) GB583277A (en)

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