JPS5656087A - Trunk circuit - Google Patents

Trunk circuit

Info

Publication number
JPS5656087A
JPS5656087A JP13144879A JP13144879A JPS5656087A JP S5656087 A JPS5656087 A JP S5656087A JP 13144879 A JP13144879 A JP 13144879A JP 13144879 A JP13144879 A JP 13144879A JP S5656087 A JPS5656087 A JP S5656087A
Authority
JP
Japan
Prior art keywords
call
amplifiers
audio amplifier
call voice
gain control
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
JP13144879A
Other languages
Japanese (ja)
Other versions
JPS6221436B2 (en
Inventor
Yoshio Koda
Yuji Matsuo
Masaharu Murata
Masao Domae
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.)
NEC Corp
Nippon Telegraph and Telephone Corp
Original Assignee
NEC Corp
Nippon Telegraph and Telephone Corp
Nippon 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 NEC Corp, Nippon Telegraph and Telephone Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP13144879A priority Critical patent/JPS5656087A/en
Publication of JPS5656087A publication Critical patent/JPS5656087A/en
Publication of JPS6221436B2 publication Critical patent/JPS6221436B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/42—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:To make it possible to prevent an abnormal sound from being sent out and a call voice from getting lower by providing an audio amplifier whose gain is adjusted automatically according to a mean voice level during a telephone call and a by-passing circuit for the audio amplifier. CONSTITUTION:When control part CONT detects a transition in a busy state, relay LP of trunk circuit TRK is put into operation to extend call lines 40 and 41 to audio amplifier AMP and hydrid transformers 32 and 33 in AMP separate a call voice by directions, thereby amplifying the call voice by amplifiers 30 and 31. Amplifiers 30 and 31 have gain control. Contact 34, when this gain control operates and gains of amplifiers 30 and 31 both reach 0dB, sends an output and the information is read out by CONT to reset relay LP, thereby forming the by-passing circuit for TRK. Thus, the transmission of an abnormal sound accompanying the audible signal of a calling tone until the level control of AMP operates and a decrease in call voice due to the excessive operation of the gain control can be prevented.
JP13144879A 1979-10-12 1979-10-12 Trunk circuit Granted JPS5656087A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13144879A JPS5656087A (en) 1979-10-12 1979-10-12 Trunk circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13144879A JPS5656087A (en) 1979-10-12 1979-10-12 Trunk circuit

Publications (2)

Publication Number Publication Date
JPS5656087A true JPS5656087A (en) 1981-05-16
JPS6221436B2 JPS6221436B2 (en) 1987-05-12

Family

ID=15058188

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13144879A Granted JPS5656087A (en) 1979-10-12 1979-10-12 Trunk circuit

Country Status (1)

Country Link
JP (1) JPS5656087A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS587965A (en) * 1981-07-07 1983-01-17 Masao Uchiumi Transfer telephone circuit

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7055725B2 (en) 2018-09-14 2022-04-18 株式会社東芝 Semiconductor device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5283104A (en) * 1975-12-31 1977-07-11 Fujitsu Ltd Switching system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5283104A (en) * 1975-12-31 1977-07-11 Fujitsu Ltd Switching system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS587965A (en) * 1981-07-07 1983-01-17 Masao Uchiumi Transfer telephone circuit

Also Published As

Publication number Publication date
JPS6221436B2 (en) 1987-05-12

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