JPH028508B2 - - Google Patents

Info

Publication number
JPH028508B2
JPH028508B2 JP56019533A JP1953381A JPH028508B2 JP H028508 B2 JPH028508 B2 JP H028508B2 JP 56019533 A JP56019533 A JP 56019533A JP 1953381 A JP1953381 A JP 1953381A JP H028508 B2 JPH028508 B2 JP H028508B2
Authority
JP
Japan
Prior art keywords
circuit
wire
amplitude
subscribers
echo
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 - Lifetime
Application number
JP56019533A
Other languages
English (en)
Japanese (ja)
Other versions
JPS57133754A (en
Inventor
Kenzo Takahashi
Takashi Sakamoto
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.)
Nippon Telegraph and Telephone Corp
Original Assignee
Nippon Telegraph and Telephone Corp
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 Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP1953381A priority Critical patent/JPS57133754A/ja
Publication of JPS57133754A publication Critical patent/JPS57133754A/ja
Publication of JPH028508B2 publication Critical patent/JPH028508B2/ja
Granted legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M3/00Automatic or semi-automatic exchanges
    • H04M3/42Systems providing special services or facilities to subscribers
    • H04M3/56Arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M3/00Automatic or semi-automatic exchanges
    • H04M3/002Applications of echo suppressors or cancellers in telephonic connections

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
JP1953381A 1981-02-12 1981-02-12 Conference telephone set Granted JPS57133754A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1953381A JPS57133754A (en) 1981-02-12 1981-02-12 Conference telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1953381A JPS57133754A (en) 1981-02-12 1981-02-12 Conference telephone set

Publications (2)

Publication Number Publication Date
JPS57133754A JPS57133754A (en) 1982-08-18
JPH028508B2 true JPH028508B2 (enrdf_load_stackoverflow) 1990-02-26

Family

ID=12001964

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1953381A Granted JPS57133754A (en) 1981-02-12 1981-02-12 Conference telephone set

Country Status (1)

Country Link
JP (1) JPS57133754A (enrdf_load_stackoverflow)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1240431A (en) * 1985-03-01 1988-08-09 Nippon Telegraph And Telephone Corporation Speech additive distribution equipment for conferencing system

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5919506B2 (ja) * 1978-04-14 1984-05-07 株式会社東芝 電話交換機
JPS54139411A (en) * 1978-04-21 1979-10-29 Nec Corp Conference trunk circuit

Also Published As

Publication number Publication date
JPS57133754A (en) 1982-08-18

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