GB691108A - Telephone exchange systems employing key-senders - Google Patents

Telephone exchange systems employing key-senders

Info

Publication number
GB691108A
GB691108A GB2830/50A GB283050A GB691108A GB 691108 A GB691108 A GB 691108A GB 2830/50 A GB2830/50 A GB 2830/50A GB 283050 A GB283050 A GB 283050A GB 691108 A GB691108 A GB 691108A
Authority
GB
United Kingdom
Prior art keywords
lever
code
earth
spring
hook
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
GB2830/50A
Other languages
English (en)
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 GB691108A publication Critical patent/GB691108A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/26—Devices for calling a subscriber
    • H04M1/515—Devices for calling a subscriber by generating or selecting signals other than trains of pulses of similar shape, or signals other than currents of one or more different frequencies, e.g. generation of dc signals of alternating polarity, coded pulses or impedance dialling

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
GB2830/50A 1949-02-09 1950-02-03 Telephone exchange systems employing key-senders Expired GB691108A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL691108X 1949-02-09

Publications (1)

Publication Number Publication Date
GB691108A true GB691108A (en) 1953-05-06

Family

ID=19807507

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2830/50A Expired GB691108A (en) 1949-02-09 1950-02-03 Telephone exchange systems employing key-senders

Country Status (2)

Country Link
BE (1) BE493792A (ko)
GB (1) GB691108A (ko)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1018912B (de) * 1951-12-07 1957-11-07 Siemens Ag Relaiskettenschaltung zur Abzaehlung von Schaltschritten

Also Published As

Publication number Publication date
BE493792A (ko)

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