MX-GT80/MX-GT90 SERVICE MANUAL COMPACT COMPONENT SYSTEM MX-GT80 / MX-GT90 STANDBY/ON STANDBY PLAY & EXCHANGE Area Suffix CD-R / RW PLAYBACK U.S.A. Canada MX-GT80 SP-MXGT80 CA-MXGT80 SP-MXGT80 STANDBY/ON PLAY & EXCHANGE STANDBY CD-R / RW PLAYBACK MX-GT90 SP-MXGT90 SP-MXGT90 CA-MXGT90 Each different point...
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MX-GT80/MX-GT90 1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits.
MX-GT80/MXGT90 Important for laser products 5.CAUTION : If safety switches malfunction, the laser is able 1.CLASS 1 LASER PRODUCT to function. 2.DANGER : Invisible laser radiation when open and inter 6.CAUTION : Use of controls, adjustments or performance of lock failed or defeated. Avoid direct exposure to beam.
MX-GT80/MX-GT90 Preventing static electricity 1. Grounding to prevent damage by static electricity Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.
MX-GT80/MXGT90 Importance administering point on the safety F102 F101 F001 Caution: For continued protection against risk of fire, replace only with same type 5A/125V for F001, 6A/125V for F101 and F102. This symbol specifies type of fast operating fuse. Precaution: Pour eviter risques de feux, remplacez le fusible de surete de F001 comme le meme type que 5A/125V, et 6A/125V pour F101 et F102.
MX-GT80/MX-GT90 Disassembly method Metal cover <Main body> Removing the metal cover (See Fig.1 to 3) Remove the six screws A on the back of the body. Remove the two screws B on both sides of the body. Remove the metal cover from the body by lifting the rear part of the cover.
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MX-GT80/MXGT90 Front panel assembly Removing the CD changer mechanism assembly (See Fig.4 and 5) Prior to performing the following procedure, remove the metal cover. Disconnect the card wire from connector CN661 on the Main board. CD changer mechanism assembly Main board...
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MX-GT80/MX-GT90 Remove the four screws E on the bottom of the Front panel assembly body. Release the two joints a on the lower right and left sides of the body using a screwdriver, and remove the front panel assembly toward the front.
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MX-GT80/MXGT90 Removing the tuner board Plastic rivet Tuner board (See Fig.11 and 12) Prior to performing the following procedure, remove Rear panel the metal cover and the CD changer mechanism assembly. Disconnect the card wire from connector CN1 on the antenna board on the right side of the body.
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MX-GT80/MX-GT90 Main board Removing the main board CN870 Front panel assembly (See Fig.16 and 17) CN871 CN315 Prior to performing the following procedure, remove the metal cover, the CD changer mechanism Amplifier board assembly, the rear panel and the tuner board.
MX-GT80/MXGT90 Removing the amplifier board / voltage Amplifier board Tie band CN703 board / heat sink (See Fig.19 and 20) CN704 Tie band Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly and the rear panel.
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MX-GT80/MX-GT90 Transformer board Removing power transformer CN250 Tie band assembly (See Fig.21 and 22) CN220 Prior to performing the following procedure, remove the metal cover, the CD changer mechanism Voltage board assembly and the rear panel. Disconnect the wires from connector CN220 and Power cord CN250 on the transformer board.
MX-GT80/MXGT90 Head amplifier <Front panel assembly> & Mechanism control board CN306 Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly and the front panel assembly. Removing cassette mechanism assembly (See Fig.24) Disconnect the card wire from connector CN306 on the head amplifier &...
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MX-GT80/MX-GT90 Preset / tuning switch board Removing the preset / tuning switch board (See Fig.29 and 30) Prior to performing the following procedure, remove the display system control board. Pull out the preset knob on the front panel. Remove the five screws Q attaching the preset / tuning switch board.
MX-GT80/MXGT90 Speaker section 1 (SP-MXGT80) Removing the front panel (See Fig.1) Remove the four screws A attaching the front panel on the front of the body. Pull out the front panel toward the front. Front panel Removing the speaker (tweeter) (See Fig.2)
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MX-GT80/MX-GT90 Removing the speaker (woofer) (See Fig.4 and 5) Punch panel Prior to performing the following procedures, remove the front panel. Remove the six screws D attaching the punch panel on the front of the body. Attention : When reassembling the punch panel, need to put glue all around.
MX-GT80/MXGT90 Speaker section 2 (SP-MXGT90) Removing the front panel (See Fig.1 and 2) Remove the four screws A attaching the front panel on the front of the body. Pull out the front panel toward the front and Front panel disconnect the wire from the two speaker terminals of the speaker (tweeter) on the back of the front panel.
MX-GT80/MX-GT90 Removing the speaker (squawker) (See Fig.5) Speaker (squawker) Prior to performing the following procedures, remove the front panel. Remove the four screws E attaching the speaker (squawker) on the front of the body. Disconnect the wire from the two speaker terminals of the speaker (squawker).
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MX-GT80/MXGT90 Removing the CD Servo control board (See Fig.1) 1.Remove the metal cover. 2.Remove the CD changer mechanism assembly. 3.From bottom side the CD changer mechanism assembly, remove the four screws A retaining the CD servo control CN854 board. 4.Absorb the four soldered positions "a" of the right and left motors with a soldering absorber.
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MX-GT80/MX-GT90 Stopper Check whether the lifter unit stopper has been caught into the hole at the section "e" of CD tray assembly as shown in Fig.5. Make sure that the driver unit elevator is positioned as shown in Fig.6 from to the second or fifth hole on the left side face of the CD changer mechanism assembly.
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MX-GT80/MXGT90 Cams R1, R2 assembly Removing the CD loading mechanism assembly(See Fig.10) While turning the cams R1 and R2 assembly in the arrow direction "h" ,align the shaft "i" of the CD loading mechanism assembly to the position shown in Fig.10.
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MX-GT80/MX-GT90 Removing the try select switch board Chassis assembly (See Fig.14) Remove the two screws G retaining the tray select switch board. Tray select switch board Disconnect the tray select switch board from connector CN804 on the CD servo control board.
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MX-GT80/MXGT90 Removing the actuator motor and belt Gear bracket (See Fig.18~21) Remove the two screws I retaining the gear bracket (See Fig.18). While pressing the pawl "t" fixing the gear bracket in the arrow direction, remove the gear bracket Pulley gear (See Fig.18).
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MX-GT80/MX-GT90 Slit washer Removing the cams R1/R2 assembly and cam gear q(See Fig.22) Cam R2 Slit washer Remove the slit washer fixing the cams R1 and R2 assembly. Cam gear q By removing the two pawls "w" fixing the cam R1, separate R2 from R1.
MX-GT80/MXGT90 < Cassette mechanism section > Cassette mechanism Removing the playback,recording and eraser heads (See Fig.1~3) 1. While shifting the trigger arms seen on the right side of the head mount in the arrow direction,turn Flywheel R the flywheel R in counterclockwise direction until the head mount has gone out with a click (See Fig.
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MX-GT80/MX-GT90 Removing the head amp. and mechanism control board (See Fig. 4) 1.Remove the cassette mechanism assembly. Head amplifier & 2.After turning over the cassette mechanism mechanism control board assembly,remove the five screws "A" retaining the head amplifier & mechanism control board.
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MX-GT80/MXGT90 Removing the capstan motor (See Fig. 8) Capstan motor From the joint bracket, remove the two screws "C" retaining the capstan motor. Joint bracket Removing the flywheel (See Fig. 9,10) 1.Remove the head amp. and mechanism control P.C.Board. 2.Remove the capstan motor assembly.
MX-GT80/MX-GT90 Adjustment method Measurement instruments required for adjustment Radio input signal 1. Low frequency oscillator, AM modulation frequency : 400Hz This oscillator should have a capacity to output 0dBs Modulation factor : 30% to 600ohm at an oscillation frequency of 50Hz-20kHz.
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MX-GT80/MXGT90 Arrangement of adjusting positions Cassette mechanism section (Mechanism A section) Cassette mechanism section (Back side) Head azimuth Head azimuth adjusting screw adjusting screw (Reverse side) (Forward side) Head azimuth Head azimuth Playback, recording and eraser adjusting screw adjusting screw...
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MX-GT80/MX-GT90 Tape recorder section Adjusting Items Measurement Standard Measurement method positions conditions values Confirmation Adjust the head Test tape Maximum 1.Playback the test tape TMT7036(10kHz). of head angle azimuth screw :TMT7036(10kHz) output 2.With the playback mechanism or recording & only when the...
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MX-GT80/MXGT90 Electrical performance Adjusting Items Measurement Standard Measurement method positions conditions values Adjustment of AC-225 *Mode : Forward or 1.With the recording and playback mechanism, recording bias :4.20 A reverse mode load the test tapes(AC-225 to TYP ),and set the...
MX-GT80/MX-GT90 Flow of functional operation until TOC read Check Point Slider turns REST Play Key Power ON Confirm that the voltage at the pin5 SW ON. of CN801 is "H"\"L"\"H". Automatic tuning of TE offset Check that the voltage at the...
MX-GT80/MXGT90 Maintenance of laser pickup Replacement of laser pickup (1) Cleaning the pick up lens Before you replace the pick up, please try to Turn off the power switch and, disconnect the clean the lens with a alcohol soaked cotton power cord from the ac outlet.
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MX-GT80/MXGT90 BA3835S (IC812) : SPI B.P.F. 1.Block Diagrams BIASC BIAS AOUT VREFC VREF REFERENCE RREF TEST CURRENT N.C. N.C. PEAK 105Hz HOLD N.C. N.C. PEAK 340Hz HOLD PEAK 1kHz DIFOUT HOLD PEAK 3.4kHz HOLD 10.5kHz PEAK HOLD 2.Pin Function Symbol Function Decoupling condenser connection terminal.
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MX-GT80/MX-GT90 BU2092/F(IC811):PORT EXPANDER 1.Terminal Layout DATA CLOCK CONTROL CIRCUIT 2.Pin Function Symbol Function Pin No. Connect to GND DATA Serial Data input CLOCK Shift Clock of Data Latch Clock of Data 5~16 Q0~Q11 Parallel Data Output Latch Data OUTPUT ON OFF...
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MX-GT80/MXGT90 LA1838(IC1): FM AM IF AMP&detector, FM MPX decoder 1. Block Diagram DECODER RF.AMP ANIT-BIRDIE MUTE BUFF STEREO P-DET AM IF PILOT 384KHz COMP S-METER AM/FM S-CLRVE S-METER IF-BUFF TUNING STEREO DRIVE DRIVE FM IF 2. Pin Function Symbol Function...
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MX-GT80/MX-GT90 LA6541-X (IC801) : Servo driver 1. Pin Layout & block diagram Vref Vin4 Vin3 Level B T L B T L Level RESET shift driver driver shift Level B T L B T L Level Regulator shift driver driver...
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MX-GT80/MX-GT90 MN101C35DEA1 (IC810) : System controller Pin function (1/2) Symbol Function Pin No. VC3 Serial data output KCMND VC3 status input MSTAT VC3 Serial clock KCLK SLC/TUNER data output DATAOUT TUNER data input DATAIN SLC/TUNER clock Not used Power supply +5V...
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MX-GT80/MXGT90 Pin function (2/2) Symbol Function Pin No. FL segment control signal output 64~85 P22~P1 Tuner chip enable TUCE System mute SMUTE Skip LED SEARCH LE LED Control signal output (CD1) CD1 LED LED Control signal output (CD2) CD2 LED...
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MX-GT80/MX-GT90 MN662748RPM (IC651) : Digital servo & digital signal processer 1. Pin layout 20 ~ 41 ~ 2.Block diagram AVSS1 LRCKIN(MSEL) 8TIMES AVDD1 BCLK(SSEL) DIGITAL OVER SAMPUNC OUTR SRDATAIN DEEMPHSIS 1BIT DIGITAL FILTER (PSEL) LOGIC IOSEL CLVS BLKCK OUTL CLDCK...
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MX-GT80/MXGT90 3. Pin function Dymbol I/O Function Symbol I/O Function BCLK Not used Tracking error shunt signal output (H:shunt) PLLF2 LRCK Not used TOFS Not used SRDATA WVEL Not used Not used Power supply (Digital) DVDD1 RF signal input DVSS1...
MX-GT80/MX-GT90 VICTOR COMPANY OF JAPAN, LIMITED AUDIO & COMMUNICATION BUSINESS DIVISION PERSONAL & MOBILE NETWORK BUSINESS UNIT. 10-1,1chome,Ohwatari-machi,Maebashi-city,371-8543,Japan Printed in Japan (No.20912) 200102(V)
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