GB1436460A - Telephone systems - Google Patents

Telephone systems

Info

Publication number
GB1436460A
GB1436460A GB3947573A GB3947573A GB1436460A GB 1436460 A GB1436460 A GB 1436460A GB 3947573 A GB3947573 A GB 3947573A GB 3947573 A GB3947573 A GB 3947573A GB 1436460 A GB1436460 A GB 1436460A
Authority
GB
United Kingdom
Prior art keywords
line
relay
key telephone
hold
signals
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
GB3947573A
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.)
AT&T Corp
Original Assignee
Western Electric Co Inc
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 Co Inc filed Critical Western Electric Co Inc
Publication of GB1436460A publication Critical patent/GB1436460A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/002—Arrangements for interconnection not involving centralised switching with subscriber controlled access to a line, i.e. key telephone systems
    • H04M9/005—Arrangements for interconnection not involving centralised switching with subscriber controlled access to a line, i.e. key telephone systems with subscriber controlled access to an exchange line
    • H04M9/006—Exchange line circuits

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
GB3947573A 1972-08-23 1973-08-21 Telephone systems Expired GB1436460A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US28292172A 1972-08-23 1972-08-23

Publications (1)

Publication Number Publication Date
GB1436460A true GB1436460A (en) 1976-05-19

Family

ID=23083695

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3947573A Expired GB1436460A (en) 1972-08-23 1973-08-21 Telephone systems

Country Status (11)

Country Link
US (1) US3795776A (US20070167544A1-20070719-C00007.png)
JP (1) JPS5830794B2 (US20070167544A1-20070719-C00007.png)
AU (1) AU5933173A (US20070167544A1-20070719-C00007.png)
BE (1) BE803833A (US20070167544A1-20070719-C00007.png)
CA (1) CA984982A (US20070167544A1-20070719-C00007.png)
DE (1) DE2341827C2 (US20070167544A1-20070719-C00007.png)
FR (1) FR2197293B1 (US20070167544A1-20070719-C00007.png)
GB (1) GB1436460A (US20070167544A1-20070719-C00007.png)
IT (1) IT994635B (US20070167544A1-20070719-C00007.png)
NL (1) NL7311384A (US20070167544A1-20070719-C00007.png)
SE (1) SE394170B (US20070167544A1-20070719-C00007.png)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2163624A (en) * 1984-08-23 1986-02-26 Thomas Makepeace Lott Line condition detection circuit

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3991282A (en) * 1974-12-27 1976-11-09 Feil Thomas E Multi station telephone switching system

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3239610A (en) * 1962-12-26 1966-03-08 Bell Telephone Labor Inc Line circuit for key telephone system
US3283083A (en) * 1963-03-13 1966-11-01 American Telephone & Telegraph Telephone subscriber's line circuit
US3436488A (en) * 1966-03-17 1969-04-01 Bell Telephone Labor Inc Line circuit for a key telephone system utilizing a single multifunction supervisory relay
US3647983A (en) * 1969-08-25 1972-03-07 San Bar Electronics Corp Key system line card circuit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2163624A (en) * 1984-08-23 1986-02-26 Thomas Makepeace Lott Line condition detection circuit

Also Published As

Publication number Publication date
FR2197293A1 (US20070167544A1-20070719-C00007.png) 1974-03-22
AU5933173A (en) 1975-02-20
CA984982A (en) 1976-03-02
JPS5830794B2 (ja) 1983-07-01
IT994635B (it) 1975-10-20
DE2341827C2 (de) 1983-06-09
SE394170B (sv) 1977-06-06
NL7311384A (US20070167544A1-20070719-C00007.png) 1974-02-26
DE2341827A1 (de) 1974-03-07
BE803833A (fr) 1973-12-17
FR2197293B1 (US20070167544A1-20070719-C00007.png) 1977-09-16
US3795776A (en) 1974-03-05
JPS4965110A (US20070167544A1-20070719-C00007.png) 1974-06-24

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PCNP Patent ceased through non-payment of renewal fee