JPS6439141A - Input level control system - Google Patents

Input level control system

Info

Publication number
JPS6439141A
JPS6439141A JP19484387A JP19484387A JPS6439141A JP S6439141 A JPS6439141 A JP S6439141A JP 19484387 A JP19484387 A JP 19484387A JP 19484387 A JP19484387 A JP 19484387A JP S6439141 A JPS6439141 A JP S6439141A
Authority
JP
Japan
Prior art keywords
gain
training signal
modem
input level
coding
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
JP19484387A
Other languages
Japanese (ja)
Inventor
Yukihiro Ando
Zen Hirano
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 JP19484387A priority Critical patent/JPS6439141A/en
Publication of JPS6439141A publication Critical patent/JPS6439141A/en
Pending legal-status Critical Current

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  • Transmission Systems Not Characterized By The Medium Used For Transmission (AREA)

Abstract

PURPOSE:To control a voice band compression coding device at an optimum input level by varying the gain in response to detection of a MODEN training signal. CONSTITUTION:The gain of an amplifier 4 serving as a gain varying means of a voice band compression coding device is shown by 20logR2/R1 or 20logR3/R1 and varied by the resistances R2 and R3. A selector 5 performs the switch and connection between the R2 and R3 to vary the gain of the amplifier 4 when a training signal detecting circuit 1 detects a MODEM training signal. Thus a voice coding part 8 and a MODEM coding part 9 are switched by selectors 7 and 10 when the MODEM training signal is detected. The signal subjected to the A/D conversion 6 is supplied to the part 9 and the coding output is transmitted via the selector 10.
JP19484387A 1987-08-04 1987-08-04 Input level control system Pending JPS6439141A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19484387A JPS6439141A (en) 1987-08-04 1987-08-04 Input level control system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19484387A JPS6439141A (en) 1987-08-04 1987-08-04 Input level control system

Publications (1)

Publication Number Publication Date
JPS6439141A true JPS6439141A (en) 1989-02-09

Family

ID=16331197

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19484387A Pending JPS6439141A (en) 1987-08-04 1987-08-04 Input level control system

Country Status (1)

Country Link
JP (1) JPS6439141A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03203466A (en) * 1989-12-29 1991-09-05 Sharp Corp Modulator and demodulator

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03203466A (en) * 1989-12-29 1991-09-05 Sharp Corp Modulator and demodulator

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