GB652657A - Alarm and automatic switching systems - Google Patents

Alarm and automatic switching systems

Info

Publication number
GB652657A
GB652657A GB12366/48A GB1236648A GB652657A GB 652657 A GB652657 A GB 652657A GB 12366/48 A GB12366/48 A GB 12366/48A GB 1236648 A GB1236648 A GB 1236648A GB 652657 A GB652657 A GB 652657A
Authority
GB
United Kingdom
Prior art keywords
amplifier
relay
output
rectifier
contacts
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
GB12366/48A
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.)
RCA Corp
Original Assignee
RCA Corp
Radio Corporation of America
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 RCA Corp, Radio Corporation of America filed Critical RCA Corp
Priority to GB12366/48A priority Critical patent/GB652657A/en
Publication of GB652657A publication Critical patent/GB652657A/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
    • H03F1/542—Replacing by standby devices

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Transmitters (AREA)

Abstract

652,657. Programme transmission. RADIO CORPORATION OF AMERICA. May 5, 1948, No. 12366. Convention date, May 22, 1947. [Class 40 (iv)] [Also in Group XL (c)] In a signalling system comprising two amplifiers or two transmitters, one being in use and the other spare, a relay circuit dependent on the relative magnitudes of the electrical energy at the input and output of the amplifier or transmitter in use switches in the spare amplifier or transmitter and disconnects the one in use when the relative magnitudes change. As shown, the input is fed to the regular amplifier 2 and the output is fed through contacts 5 and 7 of a relay to the output transformer T, a portion of the output being supplied to a rectifier 9. The emergency amplifier 3 and an amplifier 4 for the relay circuit are also connected to the input, the output of the amplifier 4 being supplied to a rectifier 11 connected to rectifier 9 and arranged to provide a zero or slightly negative potential at the junction 10 of the rectifiers. A relay amplifier 12 is connected to the junction 10 and under normal conditions the relay is inoperative and the amplifier 2 supplies the output, loss of gain or failure of the amplifier 2 causing the rectified component from rectifier 11 to become greater than that from rectifier 9 with a resultant positive potential at the junction 10. This causes the relay to operate and connect the amplifier 3 to the output transformer through contacts 6 and 7, contacts 14, 15 operating an alarm circuit, and contacts 16, 17 completing a holding circuit. The amplifier 2 may be switched back into circuit by opening the switch 19. In an alternative arrangement, Fig. 2 (not shown), the relay amplifier 12 is replaced by a thyratron valve, this eliminating the need for relay contacts 16, 17. The system may be applied to a radio transmitter and emergency transmitter, Fig. 3 (not shown), or used in programme material amplifiers and circuits for relaying material to telephone lines, and utilized to keep the equipment in operation although unattended.
GB12366/48A 1948-05-05 1948-05-05 Alarm and automatic switching systems Expired GB652657A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB12366/48A GB652657A (en) 1948-05-05 1948-05-05 Alarm and automatic switching systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB12366/48A GB652657A (en) 1948-05-05 1948-05-05 Alarm and automatic switching systems

Publications (1)

Publication Number Publication Date
GB652657A true GB652657A (en) 1951-04-25

Family

ID=22061499

Family Applications (1)

Application Number Title Priority Date Filing Date
GB12366/48A Expired GB652657A (en) 1948-05-05 1948-05-05 Alarm and automatic switching systems

Country Status (1)

Country Link
GB (1) GB652657A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2949786A (en) * 1960-08-23 Time-delay control circuit for directional gyro erection system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2949786A (en) * 1960-08-23 Time-delay control circuit for directional gyro erection system

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