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

Similar Documents

Publication Publication Date Title
GB536383A (en) Improvements in frequency modulation systems for radio signalling
GB499103A (en) Alternating current signalling systems
GB481888A (en) Improvements relating to frequency selective systems and to systems for the reception of frequency-modulated waves
GB532597A (en) Improvements in telephony
US2215482A (en) Carrier wave telephony
GB562870A (en) Improvements in telephone or like systems
US2215483A (en) Carrier wave telephony system
US2806903A (en) Voice frequency signal receivers
GB523067A (en) Improvements in signal receivers for carrier telephony systems
GB608117A (en) Voice frequency ringer
GB495162A (en) Improvements in and relating to alternating current signalling systems
GB729732A (en) Improvements in and relating to automatic gain control circuits
GB657554A (en) Receiver for pulse modulated carrier signals
GB381620A (en) Improvements in electric signalling systems
GB413359A (en) Improvements in automatic telephone systems
GB462862A (en) Improvements in or relating to electrical signalling systems
GB485652A (en) Improvements in and relating to telephone systems and the like
GB553935A (en) Improvements in or relating to voice-frequency signalling systems
GB710600A (en) Improvements in or relating to voice frequency signalling system
GB494099A (en) Improvements in or relating to telegraph systems
GB299295A (en) A system of connections for telephone installations
GB1164386A (en) Frequency Separation.
GB460428A (en) Improvements in or relating to the transmission of ringing signals in carrier frequency telephony systems
GB502584A (en) Improvements in or relating to carrier telephony systems
GB548739A (en) Improvements in or relating to electrical signalling systems