GB703465A - Improvements in or relating to circuit arrangements for indirectly heated cathode thermionic valves - Google Patents

Improvements in or relating to circuit arrangements for indirectly heated cathode thermionic valves

Info

Publication number
GB703465A
GB703465A GB412052A GB412052A GB703465A GB 703465 A GB703465 A GB 703465A GB 412052 A GB412052 A GB 412052A GB 412052 A GB412052 A GB 412052A GB 703465 A GB703465 A GB 703465A
Authority
GB
United Kingdom
Prior art keywords
valves
relating
parallel
circuit arrangements
indirectly heated
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
GB412052A
Inventor
Roy Hilton
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
Priority to BE523895D priority Critical patent/BE523895A/xx
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB412052A priority patent/GB703465A/en
Publication of GB703465A publication Critical patent/GB703465A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/52—Circuit arrangements for protecting such amplifiers
    • H03F1/54—Circuit arrangements for protecting such amplifiers with tubes only
    • H03F1/544—Protection of filaments
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/1607—Supply circuits
    • H04B1/1623—Supply circuits using tubes

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Central Heating Systems (AREA)

Abstract

703,465. Valve circuits. STANDARD TELEPHONES & CABLES, Ltd. Feb. 15, 1952, No. 4120/52. Classes 40 (5) and 40 (6) To reduce the warming-up time, the normally series-connected heaters of a number of valves are connected in parallel for a brief period after switching on. The on-off switch B2, which may be operated by a telephone handset, has further contacts B1 which reverse when the handset is lifted and cause the condenser C to discharge through a relay A. The condenser C is charged in "off" position from the H.T. supply, via resistance R1. During the discharge period, which may be adjusted by means of series resistance R2, the relay A is energized and contacts A1, 2 are reversed so as to connect, the heaters of the valves V1, 2 in parallel. With a larger number of valves, the circuit may be arranged to connect the theaters in series-parallel during the warming- up periods Specification 669,524 is 'referred to.
GB412052A 1952-02-15 1952-02-15 Improvements in or relating to circuit arrangements for indirectly heated cathode thermionic valves Expired GB703465A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
BE523895D BE523895A (en) 1952-02-15
GB412052A GB703465A (en) 1952-02-15 1952-02-15 Improvements in or relating to circuit arrangements for indirectly heated cathode thermionic valves

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB412052A GB703465A (en) 1952-02-15 1952-02-15 Improvements in or relating to circuit arrangements for indirectly heated cathode thermionic valves

Publications (1)

Publication Number Publication Date
GB703465A true GB703465A (en) 1954-02-03

Family

ID=9771134

Family Applications (1)

Application Number Title Priority Date Filing Date
GB412052A Expired GB703465A (en) 1952-02-15 1952-02-15 Improvements in or relating to circuit arrangements for indirectly heated cathode thermionic valves

Country Status (2)

Country Link
BE (1) BE523895A (en)
GB (1) GB703465A (en)

Also Published As

Publication number Publication date
BE523895A (en)

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