GB243188A - Improvements in or relating to telephone systems - Google Patents

Improvements in or relating to telephone systems

Info

Publication number
GB243188A
GB243188A GB27725A GB27725A GB243188A GB 243188 A GB243188 A GB 243188A GB 27725 A GB27725 A GB 27725A GB 27725 A GB27725 A GB 27725A GB 243188 A GB243188 A GB 243188A
Authority
GB
United Kingdom
Prior art keywords
switch
numerical
circuit
switches
relay
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
GB27725A
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.)
COVENTRY AUTOM TELEPHONES Ltd
Original Assignee
COVENTRY AUTOM TELEPHONES Ltd
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 COVENTRY AUTOM TELEPHONES Ltd filed Critical COVENTRY AUTOM TELEPHONES Ltd
Priority to GB27725A priority Critical patent/GB243188A/en
Publication of GB243188A publication Critical patent/GB243188A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Monitoring And Testing Of Exchanges (AREA)

Abstract

243,188. Coventry Automatic Telephones, Ltd., and collyer, J. E. Jan. 5, 1925. A u t o m a t i c exchange systems.-In a system in which automatic switches such as numerical selectors have access over intermediate non-numerical switches to outgoing trunks, only that non-numerical switch which is next available to a particular selector is caused to preselect an idle trunk. Such a switch on being taken into use closes a circuit for causing the next available switch to preselect. Alternatively, to take care of practically simultaneous connections, the next two or more. non-numerical switches may be caused to preselect. The switch shown is accessible from a particular level of a Strowger group selector and when the preceding switch accessible on that level is taken into use the switching relay 51 thereof completes a circuit for relay 3 which connects stepping magnet 5 to the test wiper 8 so that the switch hunts until an idle two-wire inter-exchange trunk 14, 13 is reached. When this switch is subsequently seized by a group selector, earth on the release conductor 22 operates switching relay 1 which extends the connection to the preselected trunk 14, 13 and at armature 2 completes a preselecting circuit for the next available non- numerical switch. Different shelves of group selectors have different first-choice non-numerical switches but corresponding levels of all the selectors on a particular shelf have the same non- numerical switch as first-choice and the preselecting circuit for this switch is closed over a conductor 53 by a shelf relay operated when a switch on that shelf is taken into use or is raised to the appropriate level. When all the trunks accessible to a particular switch are busy, relays 101 complete a chain circuit for relay 104 which opens the preselecting circuit, connects earth over the circuit 105, 102, 11, 21 to mark all idle switches non-selectable, by the group selectors, and may also operate a meter. The invention mav be applied to system in which grading of trunks is employed, and the switches may also be provided with means for automatically freeing themselves from a faulty trunk.
GB27725A 1925-01-05 1925-01-05 Improvements in or relating to telephone systems Expired GB243188A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB27725A GB243188A (en) 1925-01-05 1925-01-05 Improvements in or relating to telephone systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB27725A GB243188A (en) 1925-01-05 1925-01-05 Improvements in or relating to telephone systems

Publications (1)

Publication Number Publication Date
GB243188A true GB243188A (en) 1925-11-26

Family

ID=9701518

Family Applications (1)

Application Number Title Priority Date Filing Date
GB27725A Expired GB243188A (en) 1925-01-05 1925-01-05 Improvements in or relating to telephone systems

Country Status (1)

Country Link
GB (1) GB243188A (en)

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