JPS5644251A - Loud speaker telephone device - Google Patents

Loud speaker telephone device

Info

Publication number
JPS5644251A
JPS5644251A JP12051479A JP12051479A JPS5644251A JP S5644251 A JPS5644251 A JP S5644251A JP 12051479 A JP12051479 A JP 12051479A JP 12051479 A JP12051479 A JP 12051479A JP S5644251 A JPS5644251 A JP S5644251A
Authority
JP
Japan
Prior art keywords
signal
needless
eliminating device
signal eliminating
constitution
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.)
Granted
Application number
JP12051479A
Other languages
Japanese (ja)
Other versions
JPS6012828B2 (en
Inventor
Meiki Yahata
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.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura 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 Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP12051479A priority Critical patent/JPS6012828B2/en
Publication of JPS5644251A publication Critical patent/JPS5644251A/en
Publication of JPS6012828B2 publication Critical patent/JPS6012828B2/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
    • H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)

Abstract

PURPOSE:To prevent surely the oscillation phenomenon before stabilization of a needless signal eliminating device, by a constitution where the mike or the speaker is disconnected at least and they are connected after stabilization of operations of the needless signal eliminating device. CONSTITUTION:When the telephone is connected to the called side by calling, ringing tone is transmitted to receiving-side line 19 and is detected through amplifier 26 by detecting circuit 23. Then, detecting circuit 23 generates the tap gain control instruction to needless signal eliminating device 13 and activates test signal generator 26 simultaneously. Test signal generator 24 generates a signal to set the tap gain of needless signal eliminating device 13, and this signal is given to needless signal eliminating device 13 through switch 20 and buffer amplifier 25. As a result, needless signal eliminating device 13 eliminates needless signals such as the leakage signal dependent upon hybrid transformer 11 and the reflection signal from service line 12.
JP12051479A 1979-09-19 1979-09-19 public address telephone equipment Expired JPS6012828B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12051479A JPS6012828B2 (en) 1979-09-19 1979-09-19 public address telephone equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12051479A JPS6012828B2 (en) 1979-09-19 1979-09-19 public address telephone equipment

Publications (2)

Publication Number Publication Date
JPS5644251A true JPS5644251A (en) 1981-04-23
JPS6012828B2 JPS6012828B2 (en) 1985-04-03

Family

ID=14788098

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12051479A Expired JPS6012828B2 (en) 1979-09-19 1979-09-19 public address telephone equipment

Country Status (1)

Country Link
JP (1) JPS6012828B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2086522C (en) * 1991-04-30 1996-12-24 Kabushiki Kaisha Toshiba Speech communication apparatus equipped with echo canceller

Also Published As

Publication number Publication date
JPS6012828B2 (en) 1985-04-03

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