JPS5799070A - Amplification type telephone set - Google Patents

Amplification type telephone set

Info

Publication number
JPS5799070A
JPS5799070A JP17458980A JP17458980A JPS5799070A JP S5799070 A JPS5799070 A JP S5799070A JP 17458980 A JP17458980 A JP 17458980A JP 17458980 A JP17458980 A JP 17458980A JP S5799070 A JPS5799070 A JP S5799070A
Authority
JP
Japan
Prior art keywords
receiver
telephone set
reception
handset
transmitter
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
JP17458980A
Other languages
Japanese (ja)
Inventor
Hideo Ishiguro
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.)
Hitachi Ltd
Original Assignee
Hitachi 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 Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP17458980A priority Critical patent/JPS5799070A/en
Publication of JPS5799070A publication Critical patent/JPS5799070A/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

Landscapes

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

Abstract

PURPOSE:To increase anti-crosstalk and anti-noise performance of an amplifying type telephone set, by supplying a DC current to a transmitter and receiver in a handset, without increasing the number of cores of a connecting cord. CONSTITUTION:A receiver 4 and a transmitter 5 are provided in a handset 1 and they are connected with a 4-cored connecting cord 3 and an amplifying type telephone set main body 2. The power supply to a transmission amplifier 7 is made with one core of the cord 3 from the power supply V3 of the main body 2 and two cores of the receiver 4. The audio signal from the transmitter 5 is amplified at an amplifier 7 and transmitted to an audio signal transmission and reception circuit 8. An audio signal SIG received from a transmission line is amplified at a reception amplifier 6 and transmitted to the receiver 4. A bridge circuit is formed with phase inversion resistors R1, R2 of the main body 2 and voltage dividing resistors R3, R4 of the handset 1, and when adjustment is made without call reception component at a point (c), the crosstalk from the reception to transmission system can be avoided.
JP17458980A 1980-12-12 1980-12-12 Amplification type telephone set Pending JPS5799070A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17458980A JPS5799070A (en) 1980-12-12 1980-12-12 Amplification type telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17458980A JPS5799070A (en) 1980-12-12 1980-12-12 Amplification type telephone set

Publications (1)

Publication Number Publication Date
JPS5799070A true JPS5799070A (en) 1982-06-19

Family

ID=15981198

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17458980A Pending JPS5799070A (en) 1980-12-12 1980-12-12 Amplification type telephone set

Country Status (1)

Country Link
JP (1) JPS5799070A (en)

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