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Extracted text from Jvc MXGT 85 V Service Manual (Ocr-read)
Page 1
MX-GT98V/MX-GT95V/MX-GT88V
MX-GT85V/MX-G78V/MX-G75V
1-2
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. Services
should be performed by qualified personnel only.
2. Alterations of the design or circuitry of the product should not be made. Any design alterations of the product
should not be made. Any design alterations or additions will void the manufacturer's warranty and will further
relieve the manufacture of responsibility for personal injury or property damage resulting therefrom.
3. Many electrical and mechanical parts in the products have special safety-related characteristics. These
characteristics are often not evident from visual inspection nor can the protection afforded by them necessarily
be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which
have these special safety characteristics are identified in the Parts List of Service Manual. Electrical
components having such features are identified by shading on the schematics and by ( ) on the Parts List in
the Service Manual. The use of a substitute replacement which does not have the same safety characteristics
as the recommended replacement parts shown in the Parts List of Service Manual may create shock, fire, or
other hazards.
4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the like to be
separated from live parts, high temperature parts, moving parts and/or sharp edges for the prevention of
electric shock and fire hazard. When service is required, the original lead routing and dress should be
observed, and it should be confirmed that they have been returned to normal, after re-assembling.
5. Leakage current check (Electrical shock hazard testing)
After re-assembling the product, always perform an isolation check on the exposed metal parts of the product
(antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control shafts, etc.) to be sure the
product is safe to operate without danger of electrical shock.
Do not use a line isolation transformer during this check.
Plug the AC line cord directly into the AC outlet. Using a "Leakage Current Tester", measure the leakage
current from each exposed metal parts of the cabinet, particularly any exposed metal part having a return
path to the chassis, to a known good earth ground. Any leakage current must not exceed 0.5mA AC (r.m.s.).
Alternate check method
Plug the AC line cord directly into the AC outlet. Use an AC voltmeter having, 1,000 ohms per volt or more
sensitivity in the following manner. Connect a 1,500 10W resistor paralleled by a 0.15 F AC-type capacitor
between an exposed metal part and a known good earth ground.
Measure the AC voltage across the resistor with the AC
voltmeter.
Move the resistor connection to each exposed metal part,
particularly any exposed metal part having a return path to
the chassis, and measure the AC voltage across the resistor.
Now, reverse the plug in the AC outlet and repeat each
measurement. Voltage measured any must not exceed 0.75 V
AC (r.m.s.). This corresponds to 0.5 mA AC (r.m.s.).
1. This equipment has been designed and manufactured to meet international safety standards.
2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.
3. Repairs must be made in accordance with the relevant safety standards.
4. It is essential that safety critical components are replaced by approved parts.
5. If mains voltage selector is provided, check setting for local voltage.
Good earth groundPlace this
probe on
each exposed
metal part. AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
1500 10W
0.15 F AC TYPE
!
Burrs formed during molding may
be left over on some parts of the
chassis. Therefore, pay attention to
such burrs in the case of
preforming repair of this system.
In regard with component parts appearing on the silk-screen printed side (parts side) of the PWB diagrams, the
parts that are printed over with black such as the resistor ( ), diode ( ) and ICP ( ) or identified by the " "
mark nearby are critical for safety.
When replacing them, be sure to use the parts of the same type and rating as specified by the manufacturer.
(Except the J&C version)
Page 2
MX-GT98V/MX-GT95V/MX-GT88V
MX-GT85V/MX-G78V/MX-G75V
1-3
Important for laser products
1.CLASS 1 LASER PRODUCT
2.DANGER : Invisible laser radiation when open and inter
lock failed or defeated. Avoid direct exposure to beam.
3.CAUTION : There are no serviceable parts inside the
Laser Unit. Do not disassemble the Laser Unit. Replace
the complete Laser Unit if it malfunctions.
4.CAUTION : The compact disc player uses invisible laser
radiation and is equipped with safety switches which
prevent emission of radiation when the drawer is open and
the safety interlocks have failed or are defeated. It is
dangerous to defeat the safety switches.5.CAUTION : If safety switches malfunction, the laser is able
to function.
6.CAUTION : Use of controls, adjustments or performance of
procedures other than those specified herein may result in
hazardous radiation exposure.
VARNING : Osynlig laserstrålning är denna del är öppnad
och spårren är urkopplad. Betrakta ej strålen.
VARO : Avattaessa ja suojalukitus ohitettaessa olet
alttiina näkymättömälle lasersäteilylle.Älä katso
säteeseen.ADVARSEL : Usynlig laserstråling ved åbning , når
sikkerhedsafbrydere er ude af funktion. Undgå
udsættelse for stråling.
ADVARSEL : Usynlig laserstråling ved åpning,når
sikkerhetsbryteren er avslott. unngå utsettelse
for stråling.
Position of labels
WARNING LABEL
!CAUTIONPlease use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.
DANGER : Invisibie laser radiation
when open and interlock or
defeated.
AVOID DIRECT EXPOSURE TO
BEAM (e) VARNING : Osynlig laserstrålning
är denna del är öppnad och spårren
är
urkopplad. Betrakta ej strålen.
(s)
VARO : Avattaessa ja suojalukitus
ohitettaessa olet alttiina
näkymättömälle lasersäteilylle.Älä
katso säteeseen. (d) ADVARSEL :Usynlig laserstråling
ved åbning , når
sikkerhedsafbrydere er ude af
funktion. Undgå udsættelse for
stråling. (f)
CLASS 1
LASER PRODUCT
CLASS 1
LASER PRODUCT
Page 37
MX-GT98V/MX-GT95V/MX-GT88V
MX-GT85V/MX-G78V/MX-G75V
1-38
TEN
TEOUT
TEBPF
VDET
VCC GND FBAL
TBAL GCTLPDLD
VREFRFIN RFN
4 5 6 7 8 11 12 13 14
RFOUT
RF_EQAGC BDO OFTR
3TENV9
10
15
22
23
21
20 NRFDET
SUBT
SUBT BCA
BCA
BCA
BCA GCA
GCA
GCA
GCA AMP AMPAMP AMP
19
18
2 VDET 32
31
30
29
27
28
17+
--
+-
+
-
+
1
3 16 25 26 24 -
+
-
+
-
+
-
+A
B C
D
E
F A
+
C
B
+
D
F
ECAGCARF
CBDOBDO
COFTROFTR
3TOUT CEA
NRFDET
FEN
FEOUT
1.Block diagram
2. Pin function
AN22000A-W (IC601) : Digital servo head amp.
Pin No.
1
2
3
4
5
6
7
8
9
10Function
APC amp. input terminal
APC amp. output terminal
Power terminal
Inversion input terminal
for RF addition amplifier
RF add amp. output terminal
AGC input terminal
Capacity connecting terminal
for AGC loop filer
AGC output terminal
Capacity connecting terminal
for HPF amplifier
3TENV output terminalPin No.
22
23
24
25
26
27
28
29
30
31
32Function
FE amp. reverse input terminal
FE amp. output terminal
GCTL & APC terminal
FBAL control terminal
TBALcontrlo terminal
Tracking signal input terminal 1
Tracking signal input terminal 2
Focus signal input terminal 4
Focus signal input terminal 2
Focus signal input terminal 3
Focus signal input terminal 1 Pin No.
11
12
13
14
15
16
17
18
19
20
21Function
For envelope detection
at the dark side of RF
BDO output terminal
For envelope detection
at the blight side of RF
OFTR output terminal
NRFDET output terminal
Ground
VRER output terminal
VDET output terminal
VDET input terminal
TE amp. output terminal
TE amp. reverse input terminal
AB C
D
E
F
G 12 3 45
2-1
MX-GT98V/MX-GT95V/MX-GT88V
MX-GT85V/MX-G78V/MX-G75V
Block diagram
FM FRONTEND
TU1
FM/DET
AM/DET
IC 1
MW RF/OSC
COIL
PLL
Synthesizer
IC2TUNER
MPXCD
AUX
AUX
IN VIDEO
OUTMAIN
FOCUS/SPINDLE/
FEED/TRACKING
BTL DRIVER
IC801
SOURCE SELECTOR
& E.VOL
IC436
MAIN HPF
MUTE SYSTEM
IC481
INPUT AMP
IC 501
HARMONICS
GENERATOR
IC 502
LPF
IC 526
CN870/CN871
CN661
CN504
FW714
CN215
CN205
CN207
CN217
CN706
J81
RELAY
RY2 RELAY
RY1
SPEAKER TERMINAL
POWER AMP
IC 701 SUB WOOFER POWER AMP
IC602MAIN
CN1
CN11
CN801 CN601 CN854 CN855
P011 P001 CN804 CN805
RF & SERVO AMP
IC601
DIGITAL SERVO
&
PROCESSOR
IC 651
UNIT MICOM
CD CHANGER
CONTROL
IC 251
L MOTOR
DRIVER
IC 851 R MOTOR
DRIVER
IC 852
CN651
CN151 CN101 CN102
IC101
VCD PROCESSOR
IC102
EPROM IC103
DRAM
IC104
VCD CONPANION CHIP
CN860/CN861
CAM0 3
CAM4 7
1SSW 3SSW
1MSW 3MSW
A+C
B+D
E F
F
T
FM SMARFTX
CD
L CAM R CAM SW1 6 PICKUP TRACKING
FOCUS FEEDM
MICOM
IC 810 FL DISPLAY
FL 801
CN880
CN870
CN911
FW901
FW915
FW915
KEY
LED
SEARCH
KNOB
LED
MAIN VOL
WOOFER VOL
SOUND MODE KEY
LED KEY1,11 CD1LED
CD2LED
CD3LED
SEARCH R,F
KEY21,22
VOL
KEY2,3,21,32,41,42 KCMND
M S TAT
KCLK
MRDYMPX VOLDA,VOLCK
M M
FMN-011A
FMV-010AM
FMB-028-3
FM
AM
DIGITAL
OUTTX
SPINDLE M
FMB-028-1
FMC-027-1
FMA-006
FMH-031-2
FMH-
031-1
FMB-028-4
FMH-031-3
FMB-028-2
CN315 IF
TAPE
CN316 CN306
CN305
PB/REC AMP
IC302
HEAD SW
IC301
SERIAL TO PARALLEL
PORT EXTENSION
IC303
SOLENOID DRIVE FOR RP MECHA
Q3314 Q3315 SOLENOID DRIVE FOR PB MECHA
Q3312 Q3313
CN301 CN302
FW301 CN303
CN333
M DRIVER
R
L R
L PB MECHA HEAD
RP MECHA HEAD
SLCKEY
1~2
SLCKEY1 2 PHOTO A,BSW302
SW306
IC331
SOLENOID
SW303
SW304
SW305
SW316
SOLENOID
IC332
SLCKEY2
PHB
SLCK
PHA
PB MECHA PP MECHA
FMP-007-2
FMP-007-1
MIC JACK 1,2
(Only US)
LPF& ECHO MIX
IC902 KARAOKE
IC446
MIC MIC
