GB318569A - Improvements in signalling arrangements, particularly for use in telephone systems - Google Patents

Improvements in signalling arrangements, particularly for use in telephone systems

Info

Publication number
GB318569A
GB318569A GB1641928A GB1641928A GB318569A GB 318569 A GB318569 A GB 318569A GB 1641928 A GB1641928 A GB 1641928A GB 1641928 A GB1641928 A GB 1641928A GB 318569 A GB318569 A GB 318569A
Authority
GB
United Kingdom
Prior art keywords
relay
condenser
signal
currents
operate
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
GB1641928A
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.)
WESTERN ELECTRIC Y
Original Assignee
WESTERN ELECTRIC Y
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 WESTERN ELECTRIC Y filed Critical WESTERN ELECTRIC Y
Priority to GB1641928A priority Critical patent/GB318569A/en
Priority to FR657642D priority patent/FR657642A/en
Publication of GB318569A publication Critical patent/GB318569A/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)
  • Mobile Radio Communication Systems (AREA)

Abstract

318,569. Standard Telephones & Cables, Ltd., (Western Electric Co., Inc.). June 6, 1928. Manual exchange systems.-In a system in which calling &c. signals are transmitted by currents within the range of voice-frequencies, discrimination between momentarily-occurring voice currents of signal frequency and the actual signal currents is determined by associating a condenser with a relay in such a way that the relay only responds when the duration of the signal frequencies exceeds the charging time of the condenser. Fig. 2 shows combined signal transmitting and receiving means at the junction of a local line with a toll line. Low-frequency ringing currents incoming from the left operate relay 31 which in turn energizes relay 61 thereby connecting voice-frequency signal currents VF over the toll line to the right. In order to ensure that the signal currents are applied for a sufficient time to operate the signal receiver at the other end, an auxiliary relay 37 operated by relay 61 through a condenser 35 maintains relay 61 operated independent of relay 31 until condenser 35 is fully charged. Signal currents incoming over the toll line operate relay 42 causing the interruption of normal circuits for relays 43, 45, the latter however remaining operated for a short period over condenser 48. If the signal currents exceed the charging time of this condenser, relay 45 relapses and causes relay 32 to connect low-frequency source LF to the local line. The condenser is connected in series with a low resistance so that it will immediately discharge even if the signal currents are only momentarily interrupted. In a modification, Fig. 3, relay 58 controlling relay 32 is normally de-energized. When relay 54 falls back on the receipt of a signal, battery 56 is connected to relay 58 and condenser 60 in parallel but the relay does not get sufficient current to operate until the condenser is charged. The invention is stated to be applicable also to carrier and radio systems. Specification 208,038 is referred to.
GB1641928A 1928-06-06 1928-06-06 Improvements in signalling arrangements, particularly for use in telephone systems Expired GB318569A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB1641928A GB318569A (en) 1928-06-06 1928-06-06 Improvements in signalling arrangements, particularly for use in telephone systems
FR657642D FR657642A (en) 1928-06-06 1928-07-18 Improvements in electric wave signaling systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1641928A GB318569A (en) 1928-06-06 1928-06-06 Improvements in signalling arrangements, particularly for use in telephone systems

Publications (1)

Publication Number Publication Date
GB318569A true GB318569A (en) 1929-09-06

Family

ID=10076976

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1641928A Expired GB318569A (en) 1928-06-06 1928-06-06 Improvements in signalling arrangements, particularly for use in telephone systems

Country Status (2)

Country Link
FR (1) FR657642A (en)
GB (1) GB318569A (en)

Also Published As

Publication number Publication date
FR657642A (en) 1929-06-06

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