JPS5640354A - Conference telephone connection system - Google Patents

Conference telephone connection system

Info

Publication number
JPS5640354A
JPS5640354A JP11688879A JP11688879A JPS5640354A JP S5640354 A JPS5640354 A JP S5640354A JP 11688879 A JP11688879 A JP 11688879A JP 11688879 A JP11688879 A JP 11688879A JP S5640354 A JPS5640354 A JP S5640354A
Authority
JP
Japan
Prior art keywords
circuit
conference
service
channel
polarity
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.)
Pending
Application number
JP11688879A
Other languages
Japanese (ja)
Inventor
Shinsuke Kadota
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon 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
Application filed by NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP11688879A priority Critical patent/JPS5640354A/en
Publication of JPS5640354A publication Critical patent/JPS5640354A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/42—Systems providing special services or facilities to subscribers
    • H04M3/56—Arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities

Abstract

PURPOSE:To perform conference telephone service only with a simple circuit and normal telephone sets without conference terminals and conference control units, by controlling call signal transmission and the service current polarity from the line circuit. CONSTITUTION:For starting of conference connection, the subscriber dials a number assigned to line circuit 102 from telephone set 103 and calls channel control unit 201 through circuit 102. When detecting the call signal from circuit 102, circuit 201 closes automatically the loop of the channel to respond to it and extends each channel to sound mixing circuit 107. Here, the connection route between the calling subscriber and the conference telephone set is similar to the conventional route. When the conference subscriber breaks away from conference service, he hooks off the handset normally. Circuit 102 includes a function which inverts the polarity of the service current for channel release, and circuit 201 breaks the service circuit between circuit 107 and itself when detecting polarity inversion.
JP11688879A 1979-09-12 1979-09-12 Conference telephone connection system Pending JPS5640354A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11688879A JPS5640354A (en) 1979-09-12 1979-09-12 Conference telephone connection system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11688879A JPS5640354A (en) 1979-09-12 1979-09-12 Conference telephone connection system

Publications (1)

Publication Number Publication Date
JPS5640354A true JPS5640354A (en) 1981-04-16

Family

ID=14698114

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11688879A Pending JPS5640354A (en) 1979-09-12 1979-09-12 Conference telephone connection system

Country Status (1)

Country Link
JP (1) JPS5640354A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02277366A (en) * 1989-04-19 1990-11-13 Hitachi Terekomu Technol:Kk Conference speech system

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52115607A (en) * 1976-03-24 1977-09-28 Nec Corp Conference telephone system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52115607A (en) * 1976-03-24 1977-09-28 Nec Corp Conference telephone system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02277366A (en) * 1989-04-19 1990-11-13 Hitachi Terekomu Technol:Kk Conference speech system

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