GB499103A - Alternating current signalling systems - Google Patents

Alternating current signalling systems

Info

Publication number
GB499103A
GB499103A GB13457/38A GB1345738A GB499103A GB 499103 A GB499103 A GB 499103A GB 13457/38 A GB13457/38 A GB 13457/38A GB 1345738 A GB1345738 A GB 1345738A GB 499103 A GB499103 A GB 499103A
Authority
GB
United Kingdom
Prior art keywords
rectifier
bridge
circuit
relay
frequencies
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
GB13457/38A
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
Publication of GB499103A publication Critical patent/GB499103A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
    • H04Q1/446—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency
    • H04Q1/4465—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency the same frequency being used for all signalling information, e.g. A.C. nr.9 system

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Amplifiers (AREA)

Abstract

499,103. Automatic exchange systems. STANDARD TELEPHONES & CABLES, Ltd. May 5, 1938, No. 13457. Convention date, May 14, 1937. [Class 40 (iv)] Voice-frequency dialling and supervisory signals from a line L are amplified by a valve 10 and passed to a relay-controlling rectifier 30 through a bridge 22, 23, 25 (26, 27) which is balanced at the frequency to which the relay is to respond. A circuit comprising a rectifier 13, which shares the amplifier cathode, and a condenser 28 with a leak 29 in the grid circuit of the rectifier, is connected to the diagonal points a, b of the bridge. When signals of frequencies other than that to which the circuit 26, 27 is tuned are present, the bridge is unbalanced and the resulting currents in the diagonal a, b are rectified and charge condenser 28 so as to paralyse the rectifier 30. As shown, the amplifier feeds two similar signal receivers responsive respectively to frequencies of 1200 # and 1800 #.
GB13457/38A 1937-05-14 1938-05-05 Alternating current signalling systems Expired GB499103A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US142619A US2138613A (en) 1937-05-14 1937-05-14 Signaling system

Publications (1)

Publication Number Publication Date
GB499103A true GB499103A (en) 1939-01-18

Family

ID=22500591

Family Applications (1)

Application Number Title Priority Date Filing Date
GB13457/38A Expired GB499103A (en) 1937-05-14 1938-05-05 Alternating current signalling systems

Country Status (3)

Country Link
US (1) US2138613A (en)
FR (1) FR837917A (en)
GB (1) GB499103A (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2923918A (en) * 1960-02-02 Adler
US2604518A (en) * 1945-11-26 1952-07-22 Norman J Oliver Radio control system receiver
BE478607A (en) * 1945-12-20
FR928242A (en) * 1946-05-18 1947-11-21 Materiel Telephonique Electrical signaling systems
NL68564C (en) * 1946-10-02

Also Published As

Publication number Publication date
FR837917A (en) 1939-02-23
US2138613A (en) 1938-11-29

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