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 valvesInfo
- 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
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.
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) |
-
0
- BE BE523895D patent/BE523895A/xx unknown
-
1952
- 1952-02-15 GB GB412052A patent/GB703465A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
BE523895A (en) |
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