JPS57142063A - Audio switch circuit - Google Patents

Audio switch circuit

Info

Publication number
JPS57142063A
JPS57142063A JP2805081A JP2805081A JPS57142063A JP S57142063 A JPS57142063 A JP S57142063A JP 2805081 A JP2805081 A JP 2805081A JP 2805081 A JP2805081 A JP 2805081A JP S57142063 A JPS57142063 A JP S57142063A
Authority
JP
Japan
Prior art keywords
reception
amplifier
circuit
transmission
variable loss
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
JP2805081A
Other languages
Japanese (ja)
Other versions
JPS6331142B2 (en
Inventor
Hiroyuki Mori
Yozo Sudo
Toru Yokoyama
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP2805081A priority Critical patent/JPS57142063A/en
Publication of JPS57142063A publication Critical patent/JPS57142063A/en
Publication of JPS6331142B2 publication Critical patent/JPS6331142B2/ja
Granted 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
    • H04M9/10—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic with switching of direction of transmission by voice frequency

Landscapes

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

Abstract

PURPOSE:To make the switching from transmission to reception smoothly, independently of the gain of an amplifier in a reception circuit of loud speaking telephone set, by controlling variable loss circuits for transmission and reception reciprocally. CONSTITUTION:A transmission signal from a microphone 1 is amplified at an amplifier 2 and transmitted to a line via a variable loss circuit 3, an amplifier 4, and an antiside tone circuit 11. A reception signal drives a speaker 12 via an amplifier 16a, a variable loss circuit 14 and an amplifier 13. A variable loss circuit 15a and the amplifier 16a are reciprocally controlled interlockingly. A comparator 8 compares the transmission level with the reception level and controls the circuits 3 and 14 recoprocally and also an auxiliary transmission variable loss circuit 5 and an auxiliary reception variable loss circuit 15a reciprocally. Thus, the switching from the transmission to the reception state can smoothly be made independently of the gain of the amplifier in the reception circuit.
JP2805081A 1981-02-27 1981-02-27 Audio switch circuit Granted JPS57142063A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2805081A JPS57142063A (en) 1981-02-27 1981-02-27 Audio switch circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2805081A JPS57142063A (en) 1981-02-27 1981-02-27 Audio switch circuit

Publications (2)

Publication Number Publication Date
JPS57142063A true JPS57142063A (en) 1982-09-02
JPS6331142B2 JPS6331142B2 (en) 1988-06-22

Family

ID=12237922

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2805081A Granted JPS57142063A (en) 1981-02-27 1981-02-27 Audio switch circuit

Country Status (1)

Country Link
JP (1) JPS57142063A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08162660A (en) * 1994-12-07 1996-06-21 Kazuichi Torii Support device for solar cell

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08162660A (en) * 1994-12-07 1996-06-21 Kazuichi Torii Support device for solar cell

Also Published As

Publication number Publication date
JPS6331142B2 (en) 1988-06-22

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