JPS5761367A - Branch coupling circuit for conference telephone - Google Patents

Branch coupling circuit for conference telephone

Info

Publication number
JPS5761367A
JPS5761367A JP13748080A JP13748080A JPS5761367A JP S5761367 A JPS5761367 A JP S5761367A JP 13748080 A JP13748080 A JP 13748080A JP 13748080 A JP13748080 A JP 13748080A JP S5761367 A JPS5761367 A JP S5761367A
Authority
JP
Japan
Prior art keywords
loss
circuits
transmission
variable
reception
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
JP13748080A
Other languages
Japanese (ja)
Inventor
Hitoshi Fuda
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 JP13748080A priority Critical patent/JPS5761367A/en
Publication of JPS5761367A publication Critical patent/JPS5761367A/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
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M2203/00—Aspects of automatic or semi-automatic exchanges
    • H04M2203/50—Aspects of automatic or semi-automatic exchanges related to audio conference
    • H04M2203/5072—Multiple active speakers

Abstract

PURPOSE:To perform good communication by preventing the generation of a sound and a quasi-sound by deciding the loss quantity of transmission and reception sides in accordance with the size of voice level in order. CONSTITUTION:Variable loss circuits 5-8 on the transmission side and variable loss circuits 13-16 are coupled on the reception side by using coupling amplifier circuits 9-12, and at the same time these variable loss circuits are controlled by using a detection comparison control circuit 100. In case of conference telephone construction, many members speak simultaneously, first, a voice level is detected by the detection comparison control circuit 100 and in order of voice level, loss of the variable loss circuits 5-8 on the transmission side and loss of the variable loss circuits 13-16 on the reception circuit are decided and controlled so that total insertion loss on transmission and reception side becomes the specified value. Voice signals of plural number of members become suitable for conference telephone without leaning to a person.
JP13748080A 1980-09-30 1980-09-30 Branch coupling circuit for conference telephone Pending JPS5761367A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13748080A JPS5761367A (en) 1980-09-30 1980-09-30 Branch coupling circuit for conference telephone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13748080A JPS5761367A (en) 1980-09-30 1980-09-30 Branch coupling circuit for conference telephone

Publications (1)

Publication Number Publication Date
JPS5761367A true JPS5761367A (en) 1982-04-13

Family

ID=15199606

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13748080A Pending JPS5761367A (en) 1980-09-30 1980-09-30 Branch coupling circuit for conference telephone

Country Status (1)

Country Link
JP (1) JPS5761367A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57133755A (en) * 1981-02-13 1982-08-18 Nec Corp Branch coupling circuit for conference telephone set
JPS603254A (en) * 1983-06-21 1985-01-09 Nec Corp Conference talking circuit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56157164A (en) * 1980-05-07 1981-12-04 Nec Corp Conference system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56157164A (en) * 1980-05-07 1981-12-04 Nec Corp Conference system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57133755A (en) * 1981-02-13 1982-08-18 Nec Corp Branch coupling circuit for conference telephone set
JPS603254A (en) * 1983-06-21 1985-01-09 Nec Corp Conference talking circuit

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