JPS5459014A - Talking device - Google Patents

Talking device

Info

Publication number
JPS5459014A
JPS5459014A JP12611677A JP12611677A JPS5459014A JP S5459014 A JPS5459014 A JP S5459014A JP 12611677 A JP12611677 A JP 12611677A JP 12611677 A JP12611677 A JP 12611677A JP S5459014 A JPS5459014 A JP S5459014A
Authority
JP
Japan
Prior art keywords
amplifier
resistance
speaker
input
point
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
JP12611677A
Other languages
Japanese (ja)
Inventor
Hajime Karatsu
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.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial 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 Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP12611677A priority Critical patent/JPS5459014A/en
Publication of JPS5459014A publication Critical patent/JPS5459014A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/6033—Substation equipment, e.g. for use by subscribers including speech amplifiers for providing handsfree use or a loudspeaker mode in telephone sets

Landscapes

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

Abstract

PURPOSE:To ensure easy formation of an IC by constituting the circuit with the semiconductor element, resistance and capacity for the simultaneous call interphone. CONSTITUTION:The potential of the input and output terminals in amplifier 4 are set to e2 and +e3 when the resistance value of feedback resistance 6 and 7 in amplifier 4 are set to R1 and R2. Thus, the signal level becomes zero at point A by selection of the value of R1 and R2, and speaker 2 is connected. Accordingly, the input supplied from microphone 1 is delivered to line terminal 8 and 9 via amplifier 3 and 4 and not to speaker 2. On the other hand, the input signal to be given to terminal 8 and 9 is applied to speaker 2 via resistance 6, point A and amplifier 5, thus performing a simultaneous call through the double-wire system.
JP12611677A 1977-10-19 1977-10-19 Talking device Pending JPS5459014A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12611677A JPS5459014A (en) 1977-10-19 1977-10-19 Talking device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12611677A JPS5459014A (en) 1977-10-19 1977-10-19 Talking device

Publications (1)

Publication Number Publication Date
JPS5459014A true JPS5459014A (en) 1979-05-12

Family

ID=14927024

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12611677A Pending JPS5459014A (en) 1977-10-19 1977-10-19 Talking device

Country Status (1)

Country Link
JP (1) JPS5459014A (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4947006A (en) * 1972-09-11 1974-05-07

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4947006A (en) * 1972-09-11 1974-05-07

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