JPS5468208A - Automatic gain control system - Google Patents

Automatic gain control system

Info

Publication number
JPS5468208A
JPS5468208A JP13552977A JP13552977A JPS5468208A JP S5468208 A JPS5468208 A JP S5468208A JP 13552977 A JP13552977 A JP 13552977A JP 13552977 A JP13552977 A JP 13552977A JP S5468208 A JPS5468208 A JP S5468208A
Authority
JP
Japan
Prior art keywords
signal
noise
servo
automatic 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.)
Pending
Application number
JP13552977A
Other languages
Japanese (ja)
Inventor
Keizo Tashiro
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
Original Assignee
NEC 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 Electric Co Ltd filed Critical NEC Corp
Priority to JP13552977A priority Critical patent/JPS5468208A/en
Publication of JPS5468208A publication Critical patent/JPS5468208A/en
Pending legal-status Critical Current

Links

Landscapes

  • Moving Of The Head To Find And Align With The Track (AREA)

Abstract

PURPOSE: To prevent the increase in disturbance of position error signal despite entry of noise in servo signal owing to external noise by providing a differentiation circuit, a level comparator and a timer holding circuit to an automatic gain control circuit and detecting the abrupt change in the control voltage thereby maintaining the control voltage.
CONSTITUTION: The servo signal having been read from the servo face of a magnetic disc is supplied to an automatic gain amplifier 41. In positive and negative peak detection circuits 44, 45, the positive and negative peak values D, E of the servo signal are detected from the output A of an amplifier 41, whereby the position error signal F is formed. The feedback signal G which added the difference of both peak signals D, E is supervised with a differentiator 52, whereby the output signal J is obtained. This signal J is level-compared with a reference voltage Er in a level comparator 53 to detect noise, whereby the output signal K is obtained. A timer 54 is actuated by this signal K, then the signal L is sent out for the time longer than the time when adverse influence by the noise is given. When the noise enters the control signal H, the signal L causes the signal H to maintain the voltage before the entry of the noise and that signal M is applied as the control signal to the amplifier 41.
COPYRIGHT: (C)1979,JPO&Japio
JP13552977A 1977-11-10 1977-11-10 Automatic gain control system Pending JPS5468208A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13552977A JPS5468208A (en) 1977-11-10 1977-11-10 Automatic gain control system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13552977A JPS5468208A (en) 1977-11-10 1977-11-10 Automatic gain control system

Publications (1)

Publication Number Publication Date
JPS5468208A true JPS5468208A (en) 1979-06-01

Family

ID=15153893

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13552977A Pending JPS5468208A (en) 1977-11-10 1977-11-10 Automatic gain control system

Country Status (1)

Country Link
JP (1) JPS5468208A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2536196A1 (en) * 1982-11-11 1984-05-18 Sony Corp ALARM SERVO CONTROL CIRCUIT FOR OPTICAL REPRODUCTION DEVICE
JPS59229773A (en) * 1983-06-10 1984-12-24 Pioneer Electronic Corp Record information reader
JPS63222377A (en) * 1987-03-11 1988-09-16 Hitachi Ltd Disk shape information storage device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2536196A1 (en) * 1982-11-11 1984-05-18 Sony Corp ALARM SERVO CONTROL CIRCUIT FOR OPTICAL REPRODUCTION DEVICE
JPS59229773A (en) * 1983-06-10 1984-12-24 Pioneer Electronic Corp Record information reader
JPH039557B2 (en) * 1983-06-10 1991-02-08 Pioneer Electronic Corp
JPS63222377A (en) * 1987-03-11 1988-09-16 Hitachi Ltd Disk shape information storage device

Similar Documents

Publication Publication Date Title
JPS56119917A (en) Track deviation detecting system in magnetic recording and reproducing device
JPS5468208A (en) Automatic gain control system
JPS6489089A (en) Disk device
JPS57205871A (en) Loop gain adjusting circuit for tracking servo circuit
JPS57141067A (en) Reproducing device for control signal
JPS641131A (en) Tracking servo system for optical disk device
JPS5733416A (en) Automatic gain control processing system
JPS5573942A (en) Begining-of-tape setter for recording
JPS5442612A (en) Electronic rotor
JPS5315116A (en) Automatic gain adjustment system
JPS56104588A (en) Drum servo circuit
JPS5654617A (en) Automatic gain control system
JPS6421773A (en) Magnetic disk device
JPS6459641A (en) Autotracking controller
SU362332A1 (en) ALTERNATOR OF CHANGE OF ROTATION OF SHAFT ROTATION
JPS5573970A (en) Automatic gain control system
JPS55108966A (en) Magnetic head positioning speed control unit
KR930000755Y1 (en) Error detecting circuit for viss signal
JPS54155021A (en) Automatic controller for recording sensitivity of magnetic sound recorder reproducer
JPS6433729A (en) Method for detecting focus servo pull-in point
JPS5758212A (en) Magnetic disk defect detecting device
JPS5784605A (en) Automatic gain control system
JPS5714903A (en) Digital servo device
JPS56124161A (en) Intermusic detector of record player
JPS5573972A (en) Position signal detection circuit