GB540649A - Improvements in or relating to electric signalling systems - Google Patents

Improvements in or relating to electric signalling systems

Info

Publication number
GB540649A
GB540649A GB731340A GB731340A GB540649A GB 540649 A GB540649 A GB 540649A GB 731340 A GB731340 A GB 731340A GB 731340 A GB731340 A GB 731340A GB 540649 A GB540649 A GB 540649A
Authority
GB
United Kingdom
Prior art keywords
indicator
wire
substation
connect battery
relating
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
GB731340A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables 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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB731340A priority Critical patent/GB540649A/en
Publication of GB540649A publication Critical patent/GB540649A/en
Expired legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64B—LIGHTER-THAN AIR AIRCRAFT
    • B64B1/00—Lighter-than-air aircraft
    • B64B1/40—Balloons

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Structure Of Telephone Exchanges (AREA)

Abstract

540,649. Manual exchange systems. STANDARD TELEPHONES & CABLES, Ltd. and LOWRY, L. P. April 23, 1940, No. 7313. [Class 40 (iv)] A substation associated with a barrageballoon post includes contacts controlled by a wire tension indicator for sending a signal to the exchange in the event of the balloon wire becoming too taut or too slack. The substation preferably employs magneto calling, and the indicator contacts AIC connect battery across the line wires to operate the drop indicator DI, or, as shown in Fig. 2, connect battery to one wire, the drop indicator being in this case doublewound and grounded at its mid-point over a key ADK which permits simple disablement of the signalling circuit.
GB731340A 1940-04-23 1940-04-23 Improvements in or relating to electric signalling systems Expired GB540649A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB731340A GB540649A (en) 1940-04-23 1940-04-23 Improvements in or relating to electric signalling systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB731340A GB540649A (en) 1940-04-23 1940-04-23 Improvements in or relating to electric signalling systems

Publications (1)

Publication Number Publication Date
GB540649A true GB540649A (en) 1941-10-24

Family

ID=9830737

Family Applications (1)

Application Number Title Priority Date Filing Date
GB731340A Expired GB540649A (en) 1940-04-23 1940-04-23 Improvements in or relating to electric signalling systems

Country Status (1)

Country Link
GB (1) GB540649A (en)

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