GB571811A - Improvements in or relating to finder switch arrangements for use in telephone or like signalling systems - Google Patents

Improvements in or relating to finder switch arrangements for use in telephone or like signalling systems

Info

Publication number
GB571811A
GB571811A GB3019/44A GB301944A GB571811A GB 571811 A GB571811 A GB 571811A GB 3019/44 A GB3019/44 A GB 3019/44A GB 301944 A GB301944 A GB 301944A GB 571811 A GB571811 A GB 571811A
Authority
GB
United Kingdom
Prior art keywords
finders
marking
sal
normal
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
GB3019/44A
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.)
Automatic Telephone and Electric Co Ltd
Original Assignee
Automatic Telephone and Electric Co 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
Priority to NL67487D priority Critical patent/NL67487C/xx
Application filed by Automatic Telephone and Electric Co Ltd filed Critical Automatic Telephone and Electric Co Ltd
Priority to GB3019/44A priority patent/GB571811A/en
Priority to US567224A priority patent/US2442092A/en
Publication of GB571811A publication Critical patent/GB571811A/en
Priority to FR929007D priority patent/FR929007A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/58—Arrangements providing connection between main exchange and sub-exchange or satellite
    • H04Q3/62—Arrangements providing connection between main exchange and sub-exchange or satellite for connecting to private branch exchanges
    • H04Q3/625—Arrangements in the private branch exchange

Abstract

571,811. Automatic exchange systems. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd., McCLEW, J. W., and PEARCE, O. A. Feb. 18, 1944, No. 3019. [Class 40 (iv)] In a system in which normal calls are set up over finder-selector links LL1 ... LL3 and in which the setting of a selector to one of two particular positions causes the corresponding one of two special finders SAL, SBL to hunt for the line, finders of all kinds can hunt simultaneously without interference although the marking banks of the special finders are multipled and are marked over the ordinary marking banks of the normal finders. Interference with the normal finders is prevented by providing them with a common shunt field test relay LT, the marking potential being applied over one winding and the test wiper of the allotted finder being connected to the other. This relay cannot respond to any other kind of marking. A line is marked in SAL by a connection to the grounded test relay SA and in SBL by a connection to battery over a low resistance YB, the marking in both cases being applied over a back contact of the line relay to present interference by the markings in the normal finder banks. There is no tendency for SA to operate falsely via any circuit in SBL. False operation of SB via the test wiper of SAL when the switches are in corresponding positions is prevented by making SB insensitive and including a high-resistance YA in the battery connection to the test wiper of SAL.
GB3019/44A 1944-02-18 1944-02-18 Improvements in or relating to finder switch arrangements for use in telephone or like signalling systems Expired GB571811A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
NL67487D NL67487C (en) 1944-02-18
GB3019/44A GB571811A (en) 1944-02-18 1944-02-18 Improvements in or relating to finder switch arrangements for use in telephone or like signalling systems
US567224A US2442092A (en) 1944-02-18 1944-12-08 Testing arrangement for finder switches in telephone systems
FR929007D FR929007A (en) 1944-02-18 1946-06-13 Arrangement of searcher switches for use in telephone systems or similar signaling systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3019/44A GB571811A (en) 1944-02-18 1944-02-18 Improvements in or relating to finder switch arrangements for use in telephone or like signalling systems

Publications (1)

Publication Number Publication Date
GB571811A true GB571811A (en) 1945-09-10

Family

ID=9750435

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3019/44A Expired GB571811A (en) 1944-02-18 1944-02-18 Improvements in or relating to finder switch arrangements for use in telephone or like signalling systems

Country Status (4)

Country Link
US (1) US2442092A (en)
FR (1) FR929007A (en)
GB (1) GB571811A (en)
NL (1) NL67487C (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2821573A (en) * 1953-07-24 1958-01-28 Itt Dual-switch finder combination

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1837801A (en) * 1927-12-09 1931-12-22 Ass Telephone & Telegraph Co Telephone system
US1831922A (en) * 1930-02-10 1931-11-17 American Telephone & Telegraph Telephone exchange system
US2278593A (en) * 1938-03-21 1942-04-07 Fides Gmbh Telephone system

Also Published As

Publication number Publication date
US2442092A (en) 1948-05-25
NL67487C (en)
FR929007A (en) 1947-12-15

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