JVC TV-20F242 User manual

No. 51768
Nov. 2000
TV-20F242
COPYRIGHT © 2000 VICTOR COMPANY OF JAPAN, LTD.
TV-20F242
CONTENTS
SPECIFICATIONS 2
OPERATING INSTRUCTIONS (APPENDED)
SAFETY PRECAUTIONS 3
SPECIFIC SERVICE INSTRUCTIONS 4
SERVICE ADJUSTMENTS 18
GUIDE FOR REPAIRING 30
STANDARD CIRCUIT DIAGRAM (APPENDED)
PARTS LIST 53
SERVICE MANUAL
TV/VCR COMBO

2
TELEVISION
Picture Tube: 20" (measured diagonally)
Tuner Type: Quartz PLL Frequency Synthesized
Receiving Channels: VHF 2-13
UHF 14-69
CATV 14-36 (A)-(W)
37-59 (AA)-(WW)
60-85 (AAA)-(ZZZ)
86-94 (86)-(94)
95-99 (A-5)-(A-1)
100-125 (100)-(125)
01 (5A)
Antenna Input: VHF/UHF In 75 ohms coaxial
Speaker: 3", 8 ohms x 2
Audio Output Power: 1.5 + 1.5 W
VCR
Video System: VHS ,4 Rotary Heads Helical scanning System
Video Signal: NTSC Color
Cassette Tape: VHS
Video Head: 4 Head
Audio Track: Hi-Fi Sound - 2 Tracks
MONO Sound - 1 Tracks
Tape Speed: SP:33.35mm/sec
EP:11.12mm/sec
F.FWD/REW Time: Approx. 1 minutes and 48 seconds (T-120 Cassette)
Speed Search: SP 3&5 X Normal Speed
EP 9&15 X Normal Speed
GENERAL
Power Source: AC 120V 60Hz
Power Consumption: 115 Watts
Dimensions: W 19-3/4" x D 19" x H 20-1/4"
Weight: 55.2 Ibs
Inputs/Outputs: Video: In (RCA) 1Vp-p 75 ohm
Out (RCA) 1Vp-p 75 ohm
Audio: In (RCA) 300 mV/50K ohm
Out (RCA) 300 mV/1K ohm
Headphone Jack: 3.5mm Stereo mini-jack
Storage Temperature -20 ∫C ~ 60 ∫C
Operating Temperature 5 ∫C ~ 40 ∫C
Accessories:
Remote Control X 1
Batteries (AA) X 2
Design & specification are subject to change without notice.
SPECIFICATIONS

3
Operating the receiver outside of its cabinet or with its
back removed involves a shock hazard. Work on
these models should only be performed by those who
are thoroughly familiar with precautions necessary
when working on high voltage equipment.
Exercise care when servicing this chassis with power
applied. Many B plus and high voltage RF terminals are
exposed which, if carelessly contacted, can cause
serious shock or result in damage to the chassis.
Maintain interconnecting ground lead connections
between chassis, escutcheon, picture tube dag and
tuner cluster when operating the chassis.
These receivers have a "polarized" AC line cord. The AC
plug is designed to fit into standard AC outlets in one
direction only. The wide blade connects to the "ground
side" and the narrow blade connects to the "hot side" of
the AC line. This assures that the TV receiver is properly
grounded to the house wiring. If an extension cord must
be used, make sure it is of the "polarized" type.
Since the chassis of this receiver is connected to one
side of the AC supply during operation, service should
not be attempted by anyone not familiar with the
precautions necessary when working on these types
of equipment.
When it is necessary to make measurements or tests with
AC power applied to the receiver chassis, an Isolation
Transformer must be used as a safety precaution and to
prevent possible damage to transistors. The Isolation
Transformer should be connected between the TV line
cord plug and the AC power outlet.
Certain HV failures can increase X-ray radiation.
Receivers should not be operated with HV levels
exceeding the specified rating for their chassis type. The
maximum operating HV specified for the chassis used in
these receivers is 32kV 1.0kV at zero beam current with
a line voltage of 120V AC. Higher voltage may also
increase the possibility of failure in the HV supply.
It is important to maintain specified values of all
components in the horizontal and high voltage circuits
and anywhere else in the receiver that could cause a rise
in high voltage, or operating supply voltages. No changes
should be made to the original design of the receiver.
Components shown in the shaded areas on the
schematic diagram and/or identified by !in the
replacement parts list should be replaced only with
exact factory recommended replacement parts. The
use of unauthorized substitute parts may create
shock, fire, X-ray radiation, or other hazards.
To determine the presence of high voltage, use an
accurate high impedance HV meter connected
between the second anode lead and the CRT dag
grounding device. When servicing the High Voltage
System, remove static charges from it by connecting a
10k ohm resistor in series with an insulated wire (such
as a test probe) between the picture tube dag and 2nd
anode lead (have AC line cord disconnected from AC
supply).
The picture tube used in this receiver employs integral
implosion protection. Replace with a tube of the same
type number for continued safety. Do not lift picture
tube by the neck. Handle the picture tube only when
wearing shatterproof goggles and after discharging the
high voltage completely. Keep others without
shatterproof goggles away.
When removing springs or spring mounted parts from the
tuner, tuner cluster or chassis, shatterproof goggles must
be worn. Keep others without shatterproof goggles away.
Before returning the receiver to the user, perform the
following safety checks:
1.
2.
3.
Inspect all lead dress to make certain that leads are
not pinched or that hardware is not lodged between
the chassis and other metal parts in the receiver.
Replace all protective devices such as nonmetallic
control knobs, insulating fishpapers, cabinet backs,
adjustment and compartment covers or shields,
isolation resistor-capacitor networks, mechanical
insulators, etc.
To be sure that no shock hazard exists, a check for
the presence of leakage current should be made at
each exposed metal part having a return path to the
chassis (antenna, cabinet metal, screw heads,
knobs and/or shafts, escutcheon, etc.) in the
following manner.
Plug the AC line cord directly into a 120V AC receptacle.
(Do not use an Isolation Transformer during these
checks.) All checks must be repeated with the AC line
cord plug connection reversed. (If necessary, a
nonpolarized adapter plug must be used only for the
purpose of completing these checks.)
If available, measure current using an accurate leakage
current tester. Any reading of 0.35mA or more is
excessive and indicates a potential shock hazard which
must be corrected before returning the receiver to the
owner.
If a reliable leakage current tester is not available, this
alternate method of measurement should be used.
Using two clip leads, connect a 1500 ohm, 10 watt
resistor paralleled by a 0.15 F capacitor in series with
a known earth ground, such as a water pipe or conduit
and the metal part to be checked. Use a VTVM or
VOM with 1000 ohms per volt, or higher, sensitivity to
measure this AC voltage drop across the resistor. Any
reading of 0.35 volt RMS or more is excessive and
indicates a potential shock hazard which must be
corrected before returning the receiver to the owner.
TO EXPOSED
METAL PARTS TO KNOWN
EARTH GROUND
AC SCALE
VT VM
1.5K OHMS
10W
15 F
TEST PROBE
SAFETY PRECAUTIONS

4
DISASSEMBLY INSTRUCTIONS
1. REMOVAL OF MECHANICAL PARTS
AND P.C. BOARDS
1-1: BACK CABINET (Refer to Fig. 1-1)
1.
2.
3.
4.
Remove the 6 screws 1.
Remove the 2 screws 2which are used for holding the
Back Cabinet.
Remove the AC cord from the AC cord hook 3.
Remove the Back Cabinet in the direction of arrow.
Fig. 1-1
Front Cabinet
1-2: CRT PCB (Refer to Fig. 1-2)
CAUTION: BEFORE REMOVING THE ANODE CAP,
DISCHARGE ELECTRICITY BECAUSE IT
CONTAINS HIGH VOLTAGE.
BEFORE ATTEMPTING TO REMOVE OR
REPAIR ANY PCB, UNPLUG THE POWER
CORD FROM THE AC SOURCE.
1.
2.
3.
Fig. 1-2
1-3: TV/VCR BLOCK (Refer to Fig. 1-3)
1.
2.
3.
4.
Remove the 2 screws 1.
Disconnect the following connectors:
(CP401, CP502, CP4201 and CP4202).
Unlock the support 2.
Remove the TV/VCR Block in the direction of arrow.
Fig. 1-3
1-4: MAIN PCB (Refer to Fig. 1-4)
1.
2.
3.
4.
5.
6.
Remove the screw 1.
Remove the Main PCB Holder.
Remove the 2 screws 2.
Remove the 3 screws 3.
Disconnect the following connectors:
(CP810 and CP820).
Remove the Main PCB in the direction of arrow.
Remove the Anode Cap.
(Refer to REMOVAL OF ANODE CAP)
Disconnect the following connectors:
(CP802 and CP805).
Remove the CRT PCB in the direction of arrow.
1
1
2
2
1
1Back Cabinet
1
1
Front Cabinet CRT PCB
Front Cabinet 1
1
2
UP TO
RELEASE
TV/VCR Block
Main PCB Holder
VCR Block
1
Main PCB 3
2
Fig. 1-4
3
3
3
2
SPECIFIC SERVICE INSTRUCTIONS

5
1-5: DECK SHIELD PLATE (Refer to Fig. 1-5)
1.
2.
3.
1-7: JACK PLATE AND SYSCON PCB (Refer to Fig. 1-7)
1.
2.
3.
4.
5.
6.
7.
Remove the screw 1.
Remove the Syscon PCB in the direction of arrow (A).
Remove the 2 screws 2.
Remove the nut 3.
Remove the washer 4.
Unlock the 2 supports 5.
Remove the Jack Plate in the direction of arrow (B).
Jack Plate
1
Deck Holder
Syscon PCB
(A)
5
5
(B)
4
Fig. 1-7
Remove the 2 screws 1.
Remove the screw 2.
Remove the Deck Shield Plate in the direction of arrow.
2
2
3
1
Deck Shield Plate
Fig. 1-5
1-6: DECK CHASSIS (Refer to Fig. 1-6)
1.
2.
3.
Remove the 3 screws 1.
Disconnect the following connectors:
(CP1004, CP1005, CP1006, CP4001, CP4002 and
CP4003).
Remove the Deck Chassis in the direction of arrow.
11
1
Deck Chassis
Syscon PCB
Fig. 1-6
1
VCR Block
2

6
2. REMOVAL OF DECK PARTS
2-1: TOP BRACKET (Refer to Fig. 2-1)
Remove the 2 screws 1.
Slide the 2 supports 2and remove the Top Bracket.
1.
2.
NOTE
When you install the Top Bracket, install the screw (1)
first, then install the screw (2).
1
(2)
Top Bracket Top Bracket
Main Chassis
Main Chassis
2
1
(1)
2
Fig. 2-1
NOTE
When you install the Tape Guide L, install as shown in the
circle of Fig. 2-3-B. (Refer to Fig. 2-3-B)
REC Lever
Tape Guide L
Fig. 2-3-B
2-4: CASSETTE HOLDER ASS'Y (Refer to Fig. 2-4)
Move the Cassette Holder Ass'y to the front side.
Push the Locker R to remove the Cassette Side R.
Remove the Cassette Side L.
1.
2.
3.
Main Chassis
Main Chassis
Cassette Side L
Cassette Side R Locker R
Fig. 2-4
2-5: CASSETTE SIDE L/R (Refer to Fig. 2-5)
Unlock the 4 supports 1and then remove the Cassette
Side L/R.
1.
• Screw Torque: 5 ±0.5kgf•cm
2-2: FLAP LEVER/TAPE GUIDE R (Refer to Fig. 2-2)
NOTE
When you install the Cassette Side R, be sure to move the
Locker R after installing.
Cassette Side L
Cassette Side R
1
1
1
Locker R 1
Fig. 2-5
Move the Cassette Holder Ass'y to the back side.
Remove the Polyslider Washer 1.
Remove the Flap Lever.
Unlock the 3 supports 2and remove the Tape Guide R.
1.
2.
3.
4.
Fig. 2-2
2-3: TAPE GUIDE L (Refer to Fig. 2-3-A)
Move the Cassette Holder Ass'y to the back side.
Unlock the 2 supports 1and remove the Tape Guide L.
Remove the REC Lever.
1.
2.
3.
1
Main Chassis
Tape Guide L
REC Lever
Fig. 2-3-A
1
1
2
2
2
Tape Guide R
Flap Lever
Main Chassis

7
2-6: LINK ASS'Y (Refer to Fig. 2-6)
Set the Link Ass'y to the Eject position.
Remove the (A) side of the Link Ass'y first, then remove
the (B) side.
1.
2.
Main Chassis
(A)
Main Chassis
Link Ass'y
Fig. 2-6
2-7: LOADING MOTOR ASS'Y (Refer to Fig. 2-7)
Remove the Link Lever.
Remove the Dumper Spring.
Remove the 2 screws 1.
Unlock the support 2and remove the Loading Motor
Ass'y.
Unlock the 2 supports 3and remove the Deck PCB
(BOT).
1.
2.
3.
4.
5.
2-9: TENSION ASS'Y (Refer to Fig. 2-9-A)
Move the Inclined S Ass'y to the back side.
Remove the Tension Spring.
Unlock the support 1and remove the Tension Arm
Ass'y.
Remove the Tension Adjust.
Unlock the 2 supports 2and remove the Tension Band
Ass'y.
Unlock the support 3and remove the Tension Holder.
Remove the SS Brake Spring.
Remove the SS Arm Brake.
1.
2.
3.
4.
5.
6.
7.
8.
1
2
1
Loading Motor Ass'y
Link Lever
Main Chassis
•Screw Torque: 5 ±0.5kgf•cm Fig. 2-7
2-8: SENSOR COVER L3 (Refer to Fig. 2-8)
Unlock the support 1and remove the Sensor Cover L3.1.
Deck PCB
(BOT)
Link Ass'y
(B)
Dumper Spring
3
3
1
2
2
Tension Adjust
Tension Band Ass'y
Tension Spring Tension Arm Ass'y
Tension Holder
Inclined S Ass'y
Fig. 2-9-A
SS Brake Spring
SS Arm Brake
NOTE
When you install the Tension Adjust, install as shown in
Fig. 2-9-B. (Refer to Fig. 2-9-B)
Fig. 2-9-B
2-10: T BRAKE ASS'Y (Refer to Fig. 2-10)
Remove the T Brake Spring.
Remove the T Brake Ass'y.
1.
2.
T Brake Ass'y
Fig. 2-10
Adjust the direction of the Marker to inside.
T Brake Spring
Main Chassis
Sensor Cover L3
1
Fig. 2-8

8
2-11: S REEL/T REEL (Refer to Fig. 2-11)
Remove the S Reel and T Reel.
Remove the 2 Polyslider Washers 1.
1.
2.
NOTE
Do not touch the Pinch Roller. (Use gloves.)
When you install the Pinch Roller Block, install as shown
in the circle of Fig. 2-12-B. (Refer to Fig. 2-12-B)
1.
2.
NOTE
Take care not to damage the gears of the S Reel and T
Reel.
The Polyslider Washer may be remained on the back of
the reel.
Take care not to damage the shaft.
Do not touch the section "A" of S Reel and T Reel. (Use
gloves.) (Refer to Fig. 2-11) Do not adhere the stains
on it.
When you install the reel, clean the shaft and oil it (FL
OIL #6115). (If you do not oil, noise may be heard in FF/
REW mode.)
After installing the reel, adjust the height of the reel.
(Refer to MECHANICAL ADJUSTMENT)
1.
2.
3.
4.
5.
6.
Fig. 2-12-B
2-13: A/C HEAD (Refer to Fig. 2-13-A)
Remove the screw 1.
Remove the A/C Head Base.
Remove the 3 screws 2.
Remove the A/C Head and A/C Head Spring.
1.
2.
3.
4.
NOTE
Do not touch the A/C Head. (Use gloves.)
When you install the A/C Head Spring, install as shown
in Fig. 2-13-B. (Refer to Fig. 2-13-B)
When you install the A/C Head, tighten the screw (1)
first, then tighten the screw (2), finally tighten the screw
(3).
1.
2.
3.
A/C Head
2
2
A/C Head Spring
1
(3)
(1)
2
(2)
A/C Head Base
Spring Position
Fig. 2-13-B
2-14: FE HEAD (Refer to Fig. 2-14)
Remove the screw 1.
Remove the FE Head.
1.
2.
1
FE Head
•Screw Torque: 4 ±0.5kgf•cm
Fig. 2-13-A
•Screw Torque: 4 ±0.5kgf•cm (Screw 1)
S Reel
1
(A)
T Reel
(A)
1
Fig. 2-11
2-12: PINCH ROLLER BLOCK/P5-3 ARM ASS'Y
(Refer to Fig. 2-12-A)
Remove the P5 Spring.
Remove the screw 1.
Unlock the 2 supports 2and remove the Cassette
Opener.
Remove the Pinch Roller Block, Pinch Roller Arm
Spring, Pinch Roller Lever Ass'y and P5-3 Arm Ass'y.
1.
2.
3.
4.
1
2
2
P5 Spring
Cassette Opener
P5-3 Arm Ass'y
Pinch Roller Block
Pinch Roller Lever Ass'y
Main Chassis
Fig. 2-12-A
Pinch Roller Arm Spring
•Screw Torque: 5 ±0.5kgf•cm
Fig. 2-14

9
1
2
E-Ring
Middle Gear
Main Cam
Pinch Roller Cam
Joint Gear
P5 Cam
Fig. 2-17-A
NOTE
When you install the Pinch Roller Cam, P5 Cam and Main
Cam, align each marker. (Refer to Fig. 2-17-B)
Pinch Roller Cam
P5 Cam
Main Cam
Marker
Check the hole of Main
Chassis can be seen.
Fig. 2-17-B
2-18: CLUTCH ASS'Y (Refer to Fig. 2-18)
Remove the Polyslider Washer 1.
Remove the Clutch Ass'y, Ring Spring and Coupling
Gear.
Unlock the 2 supports 2and remove the Clutch Lever.
1.
2.
3.
2-16: CAPSTAN DD UNIT (Refer to Fig. 2-16)
Remove the Capstan Belt.
Remove the 3 screws 1.
Remove the Capstan DD Unit.
1.
2.
3.
•Screw Torque: 5 ±0.5kgf•cm Fig. 2-16
2-17: MIDDLE GEAR/MAIN CAM (Refer to Fig. 2-17-A)
Remove the Polyslider Washer 1, then remove the
Middle Gear.
Remove the E-Ring, then remove the Main Cam, P5
Cam and Pinch Roller Cam.
Remove the Polyslider Washer 2, then remove the
Joint Gear.
1.
2.
3.
Capstan DD Unit
Capstan Belt
11
1
Fig. 2-18
1
Clutch Ass'y
Ring Spring
Coupling Gear
Clutch Lever
2
2
2-15: AHC ASS'Y/CYLINDER UNIT ASS'Y
(Refer to Fig. 2-15)
Unlock the support 1and remove the AHC Ass'y.
Remove the 3 screws 2.
Remove the Cylinder Unit Ass'y.
1.
2.
3.
When you install the Cylinder Unit Ass'y, tighten the
screws from (1) to (3) in order while pulling the Ass'y
toward the left front direction.
NOTE
1
AHC Ass'y
Cylinder Unit Ass'y
2
2
2
•Screw Torque: 3 ±0.5kgf•cm Fig. 2-15
(1)
(3)
(2)

10
2-19: LOADING GEAR S/T ASS'Y (Refer to Fig. 2-19-A)
1.
2.
3.
4.
5.
6.
7.
8.
9.
1
2
Capstan Brake Spring Capstan Brake Ass'y
Main Rod Main Loading Gear
Tension Lever
Loading Gear T
Loading Gear
Spring
Loading Arm T Ass'y
Loading Gear S
Loading Gear
Spring
Loading Arm S Ass'y
LED Reflecter
Idler Arm Ass'y
Clutch Actuator
Remove the E-Ring 1and remove the Main Loading
Gear.
Remove the Capstan Brake Spring.
Slide the Main Rod and remove the Capstan Brake
Ass'y.
Remove the Main Rod, Tension Lever, Clutch Actuator,
Idler Arm Ass'y.
Remove the screw 2.
Remove the LED Reflecter.
Remove the Loading Arm S Ass'y and Loading Arm T
Ass'y.
Remove the Loading Gear S and Loading Gear T.
Remove the Loading Gear Spring.
2. When you install the Clutch Actuator, install as shown in
the circle of Fig. 2-19-C. (Refer to Fig. 2-19-C)
Fig. 2-19-C
Clutch Actuator
NOTE
Do not touch the roller of Guide Roller.
Fig. 2-20
Loading Gear Holder
Inclined T
P4 Cover
Guide Roller
Inclined S
1
2
3
4
4
Guide Roller
2-20: INCLINED S/T ASS'Y (Refer to Fig. 2-20)
Unlock the support 1and remove the P4 Cover.
Remove the screw 2.
Unlock the support 3and remove the Loading Gear
Holder.
Remove the Inclined S.
Remove the Inclined T.
Remove the 2 screws 4, then remove the Guide Roller.
1.
2.
3.
4.
5.
6.
•Screw Torque: 5 ±0.5kgf•cm
Fig. 2-19-A
NOTES
Loading Arm T Ass'y
Main Loading Gear
Marker
Marker
Loading Arm S Ass'y
1. When you install the Loading Arm S Ass'y, Loading Arm
T Ass'y and Main Loading Gear, align each marker.
(Refer to Fig. 2-19-B)
Fig. 2-19-B
•Screw Torque: 5 ±0.2kgf•cm (Screw 2)
•Screw Torque: 0.7 ±0.2kgf•cm (Screw 4)

11
3. REMOVAL OF ANODE CAP
Read the following NOTED items before starting work.
After turning the power off there might still be a potential
voltage that is very dangerous. When removing the
Anode Cap, make sure to discharge the Anode Cap's
potential voltage.
Do not use pliers to loosen or tighten the Anode Cap
terminal, this may cause the spring to be damaged.
*
*
REMOVAL
1. Follow the steps as follows to discharge the Anode Cap.
(Refer to Fig. 3-1.)
Connect one end of an Alligator Clip to the metal part of a
flat-blade screwdriver and the other end to ground.
While holding the plastic part of the insulated Screwdriver,
touch the support of the Anode with the tip of the
Screwdriver.
A cracking noise will be heard as the voltage is discharged.
Flip up the sides of the Rubber Cap in the direction of
the arrow and remove one side of the support.
(Refer to Fig. 3-2.)
2.
GND on the CRT
Screwdriver
Alligator Clip
Support CRT
GND on the CRT
Rubber Cap
CRT Support
Fig. 3-1
Fig. 3-2
3. After one side is removed, pull in the opposite direction
to remove the other.
NOTE
INSTALLATION
1. Clean the spot where the cap was located with a small
amount of alcohol. (Refer to Fig. 3-3.)
NOTE
Confirm that there is no dirt, dust, etc. at the spot where
the cap was located.
2.
3.
Arrange the wire of the Anode Cap and make sure the
wire is not twisted.
Turn over the Rubber Cap. (Refer to Fig. 3-4.)
Fig. 3-4
4. Insert one end of the Anode Support into the anode
button, then the other as shown in Fig. 3-5.
CRT Support Fig. 3-5
5.
6. Confirm that the Support is securely connected.
Put on the Rubber Cap without moving any parts.
Location of Anode Cap
Fig. 3-3
Take care not to damage the Rubber Cap.

12
A
B
C
D
E
F
G
H
A/C
ACC
AE
AFC
AFT
AFT DET
AGC
AMP
ANT
A.PB
APC
ASS'Y
AT
AUTO
A/V
BGP
BOT
BPF
BRAKE SOL
BUFF
B/W
C
CASE
CAP
CARR
CH
CLK
CLOCK (SY-SE)
COMB
CONV
CPM
CTL
CYL
CYL-M
CYL SENS
DATA (SY-CE)
dB
DC
DD Unit
DEMOD
DET
DEV
E
EF
EMPH
ENC
ENV
EOT
EQ
EXT
F
FBC
FE
FF
FG
FL SW
FM
FSC
FWD
GEN
GND
H.P.F
:
:
:
:
:
:
:
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:
:
:
:
:
:
:
:
:
:
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:
:
:
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:
:
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:
:
:
:
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:
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:
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:
:
Audio/Control
Automatic Color Control
Audio Erase
Automatic Frequency Control
Automatic Fine Tuning
Automatic Fine Tuning Detect
Automatic Gain Control
Amplifier
Antenna
Audio Playback
Automatic Phase Control
Assembly
All Time
Automatic
Audio/Video
Burst Gate Pulse
Beginning of Tape
Bandpass Filter
Brake Solenoid
Buffer
Black and White
Capacitance, Collector
Cassette
Capstan
Carrier
Channel
Clock
Clock (Syscon to Servo)
Combination, Comb Filter
Converter
Capstan Motor
Control
Cylinder
Cylinder-Motor
Cylinder-Sensor
Data (Syscon to Servo)
Decibel
Direct Current
Direct Drive Motor Unit
Demodulator
Detector
Deviation
Emitter
Emitter Follower
Emphasis
Encoder
Envelope
End of Tape
Equalizer
External
Fuse
Feed Back Clamp
Full Erase
Fast Forward, Flipflop
Frequency Generator
Front Loading Switch
Frequency Modulation
Frequency Sub Carrier
Forward
Generator
Ground
High Pass Filter
I
K
L
M
N
O
P
R
S
H.SW
Hz
IC
IF
IND
INV
KIL
L
LED
LIMIT AMP
LM, LDM
LP
L.P.F
LUMI.
M
MAX
MINI
MIX
MM
MOD
MPX
MS SW
NC
NR
OSC
OPE
PB
PB CTL
PB-C
PB-Y
PCB
P. CON
PD
PG
P-P
R
REC
REC-C
REC-Y
REEL BRK
REEL S
REF
REG
REW
REV, RVS
RF
RMC
RY
S. CLK
S. COM
S. DATA
SEG
SEL
SENS
SER
SI
SIF
SO
SOL
SP
STB
SW
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Head Switch
Hertz
Integrated Circuit
Intermediate Frequency
Indicator
Inverter
Killer
Left
Light Emitting Diode
Limiter Amplifier
Loading Motor
Long Play
Low Pass Filter
Luminance
Motor
Maximum
Minimum
Mixer, mixing
Monostable Multivibrator
Modulator, Modulation
Multiplexer, Multiplex
Mecha State Switch
Non Connection
Noise Reduction
Oscillator
Operation
Playback
Playback Control
Playback-Chrominance
Playback-Luminance
Printed Circuit Board
Power Control
Phase Detector
Pulse Generator
Peak-to Peak
Right
Recording
Recording-Chrominance
Recording-Luminance
Reel Brake
Reel Sensor
Reference
Regulated, Regulator
Rewind
Reverse
Radio Frequency
Remote Control
Relay
Serial Clock
Sensor Common
Serial Data
Segment
Select, Selector
Sensor
Search Mode
Serial Input
Sound Intermediate Frequency
Serial Output
Solenoid
Standard Play
Serial Strobe
Switch
KEYTO ABBREVIATIONS

13
S
T
U
V
X
Y
SYNC
SYNC SEP
TR
TRAC
TRICK PB
TP
UNREG
V
VCO
VIF
VP
V.PB
VR
V.REC
VSF
VSR
VSS
V-SYNC
VT
X'TAL
Y/C
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Synchronization
Sync Separator, Separation
Transistor
Tracking
Trick Playback
Test Point
Unregulated
Volt
Voltage Controlled Oscillator
Video Intermediate Frequency
Vertical Pulse, Voltage Display
Video Playback
Variable Resistor
Video Recording
Visual Search Fast Forward
Visual Search Rewind
Voltage Super Source
Vertical-Synchronization
Voltage Tuning
Crystal
Luminance/Chrominance

14
SERVICE MODE LIST
This unit provided with the following SERVICE MODES so you can repair, examine and adjust easily.
To enter SERVICE MODE, unplug AC cord till lost actual clock time. Then press and hold Vol (-) button of main unit and
remocon key simultaneously.
The both pressing of set key and remote control key will not be possible if clock has been set. To reset clock, either unplug
AC cord and allow at least 5 seconds before Power On.
Set Key Remocon Key Operations
VOL. (-) MIN 0Releasing of V-CHIP PASSWORD.
Horizontal position adjustment of OSD.
NOTE: Also can be adjusted by using the Adjustment MENU.
Refer to the "ELECTRICAL ADJUSTMENT" (OSD HORIZONTAL).
VOL. (-) MIN 3Adjust the SWITCHING POINT automatically.
Refer to the "ELECTRICAL ADJUSTMENT" (PG SHIFTER).
VOL. (-) MIN 4 Adjust the SWITCHING POINT manually.
Refer to the "ELECTRICAL ADJUSTMENT" (PG SHIFTER).
VOL. (-) MIN 2
Adjusting of the Tracking to the center position.
NOTE: Also can be adjusted by pressing the ATR button for more than 2 seconds
during PLAY.
VOL. (-) MIN 5
POWER ON total hours and PLAY/REC total hours are displayed on the screen.
Refer to the "PREVENTIVE CHECKS AND SERVICE INTERVALS" (CONFIRMATION
OF USING HOURS).
Can be checked of the INITIAL DATA of MEMORY IC.
Refer to the "NOTE FOR THE REPLACING OF MEMORY IC".
VOL. (-) MIN 6
VOL. (-) MIN 1 Initialization of the factory.
NOTE: Do not use this for the normal servicing.
VOL. (-) MIN 9 Display of the Adjustment MENU on the screen.
Refer to the "ELECTRICAL ADJUSTMENT" (On-Screen Display Adjustment).
VOL. (-) MIN 8 Writing of EEPROM initial data.
NOTE: Do not use this for the normal servicing.
Method Operations
Adjusting of the Tracking to the center position.
Refer to the "MECHANICAL ADJUSTMENT" (GUIDE ROLLER) and "ELECTRICAL
ADJUSTMENT" (SWITCHING POINT).
Press the ATR button on the
remote control for more than
2 seconds during PLAY.
Make the short circuit between
the test point of SERVICE and
the GND.
The EOT/BOT/Reel sensor do not work at this moment.
Refer to the "PREPARATION FOR SERVICING"

15
PREVENTIVE CHECKS AND SERVICE INTERVALS
The following standard table depends on environmental conditions and usage. Unless maintenance is properly
carried out, the following service intervals may be quite shortened as harmful effects may be had on other parts.
Also, long term storage or misuse may cause transformation and aging of rubber parts.
Parts Name
Audio Control Head
Notes
Time 500
hours 1,000
hours 1,500
hours 2,000
hours 3,000
hours
: Clean
: Replace
Full Erase Head
(Recorder only)
Capstan Belt
Pinch Roller
Capstan DD Unit
Loading Motor
Tension Band
Capstan Shaft
Tape Running
Guide Post
Cylinder Unit
Clean those parts in
contact with the tape.
Clean the rubber, and parts
which the rubber touches.
Replace when rolling
becomes abnormal.
Clean the Head
CONFIRMATION OF USING HOURS
POWER ON total hours and PLAY/REC total hours can be checked on the screen.
Total hours are displayed in 16 system of notation.
NOTE: The confirmation of using hours will not be possible if clock has been set. To reset clock, either unplug
AC cord and allow at least 5 seconds before Power On.
1.
2.
3.
Set the VOLUME to minimum.
While holding down VOLUME button on front cabinet, press key 6 on remote control simultaneously.
After the confirmation of using hours, turn off the power.
INIT 00 83
0010
0003
POWER ON
PLAY/REC
Initial setting content of MEMORY IC.
POWER ON total hours.
PLAY/REC total hours.
(16 x 16 x 16 x thousands digit value) + (16 x 16 x hundreds digit value) + (16 x tens digit value) + (ones digit value)

16
CLEANING
NOTE
After cleaning the heads with isopropyl alcohol, do not
run a tape until the heads dry completely. If the heads
are not completely dry and alcohol gets on the tape,
damage may occur.
1. AUDIO CONTROL HEAD
Wrap a piece of chamois around your finger. Dip it in
isopropyl alcohol and clean the audio control head by
wiping it horizontally. Clean the full erase head in the
same manner. (Refer to the figure below.)
Audio Control Head
2. TAPE RUNNING SYSTEM
When cleaning the tape transport system, use the
gauze moistened with isopropyl alcohol.
3. CYLINDER
Wrap a piece of chamois around your finger. Dip it in
isopropyl alcohol. Hold it to the cylinder head softly.
Turn the cylinder head counterclockwise to clean it (in
the direction of the arrow). (Refer to the figure below.)
NOTE
Do not exert force against the cylinder head. Do not move
the chamois upward or downward on the head.
Use the chamois one by one.
Cylinder Head

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Initial Data setting will not be possible if clock has been set. To reset clock, either unplug AC cord and allow
at least 5 seconds before Power On.
NOTE FOR THE REPLACING OF MEMORY IC
If a service repair is undertaken where it has been required to change the MEMORY IC, the following steps should be taken to
ensure correct data settings while making reference to TABLE 1.
NOTE:
Table 1
3.
4.
5.
6.
7.
8.
The unit will now have the correct DATA for the new MEMORY IC.
1.
2.
Fig. 1
ADDRESS is now selected and should "blink". Using the SET + or - keys on the remote, step through the ADDRESS until
required ADDRESS to be changed is reached.
Press ENTER to select DATA. When DATA is selected, it will "blink".
Again, step through the DATA using SET + or - until required DATA value has been selected.
Pressing ENTER will take you back to ADDRESS for further selection if necessary.
Repeat steps 3 to 6 until all data has been checked.
When satisfied correct DATA has been entered, turn POWER off (return to STANDBY MODE) to finish DATA input.
Enter DATA SET mode by setting VOLUME to minimum.
While holding down VOLUME button on front cabinet, press key 6 on remote control simultaneously.
ADDRESS and DATA should appear as FIG 1.
INIT 00 83
0010
0003
POWER ON
PLAY/REC
ADDRESS DATA
00
01
02
04
05
06
07
08
09
88 0A DC 14 27 1E 0E 28 01
ADDRESS DATA ADDRESS DATA ADDRESS DATA ADDRESS DATA ADDRESS DATA
79 0B 02 15 00 1F 03 29 35
A2 0C 63 16 90 20 BA
03 47 0D 0D 17 05 21 05
C3 0E 17 18 80 22 79
23 0F 0A 19 89 23 05
34 10 8C 1A A9 24 3E
1B 11 68 1B 22 25 2A
59 12 5C 1C 05 26 39
B2 13 53 1D 39 27 00

18
SERVICING FIXTURES AND TOOLS
Part No.
MHP
Remarks
Monoscope (For 4 heads model)
MHP X Value Adjustment
Color Bar, 1KHz (For 4 heads model)
Hi-Fi Audio (For 4 heads Hi-Fi model)
PTU94002 Guide Roller Adjustment
VSR Torque, Brake Torque (S Reel/T Reel Ass'y)
Brake Torque (T Reel Ass'y)
VSR Torque, Brake Torque (S Reel)
X-JG153 X Value Adjustment
Reel Disk Height Adjustment
Playback Torque, Back Tension Torque During Playback
Short Jumper Used to connect the TP1001 and GROUND
X-JG162A/X-JG162F Used to connect the Syscon PCB and Main PCB
X-JG162Y Used to connect the Syscon PCB and CRT PCB
(For 4 heads model)
VHS Alignment Tape
MHP
Torque Gauge PTU94002 Roller Driver X-JG153 X Value Adjustment
Screwdriver
Master Plane Reel Disk Height
Adjustment Jig Torque Tape Short Jumper
X-JG162A Cable (8 Pins)
X-JG162F Cable (13 Pins)
X-JG162Y Cable (5 Pins)
Tentelometer
SERVICE ADJUSTMENT

19
PREPARATION FOR SERVICING
Basic Servicing Position (In case of needing to check on all blocks)
1.
2.
3.
4.
5.
6.
Unplug the connector CP502, CP4201 and CP4202, then remove the TV/VCR Block from the set.
Unplug the connector CP810, CP820 and CP805, then remove the Main PCB from the VCR Block.
Connect as shown in the below figure using the Service Fixture.
•Connect the Syscon PCB to the Main PCB with the cable X-JG162A and X-JG162F.
•Connect the Syscon PCB to the CRT PCB with the cable X-JG162Y.
Remove the Operation PCB from the set, then connect it with the Syscon PCB.
If necessary, connect CP4202 (Front A/V Jack Input Terminal)
Short circuit between TP1001 and Ground with the Short Jumper.
The EOT, BOT and Reel Sensor do not work at this moment.
At that time, the STOP/EJECT button is available to insert and eject the Cassette Tape.
CP805
CD810
Front Cabinet
CRT PCB
Syscon PCB
CP4201
CD757
CP820
Main PCB CP810
X-JG162A
CD601
CD850
Operation PCB
Short Jumper
To Ground
X-JG162F
X-JG162Y
TP1001

20
MECHANICAL ADJUSTMENTS
1. CONFIRMATION AND ADJUSTMENT
Read the following NOTES before starting work.
•
•
Place an object which weighs between 450g~500g on
the Cassette Tape to keep it steady when you want to
make the tape run without the Cassette Holder. (Do not
place an object which weighs over 500g.)
When you activate the deck without the Cassette
Holder, short circuit between TP1001 and GND. (Refer
to ELECTRICAL ADJUSTMENT PARTS LOCATION
GUIDE) In this condition the BOT/EOT/Reel Sensor will
not function.
1-3: CONFIRMATION OF PLAYBACK TORQUE AND
BACK TENSION TORQUE DURING PLAYBACK
Load a video tape (T-120) recorded in standard speed
mode. Set the unit to the PLAY mode.
Install the tentelometer as shown in Fig. 1-3. Confirm that
the meter indicates 20 ±2gf in the beginning of playback.
1.
2.
•USING A CASSETTE TYPE TORQUE TAPE
1.
2.
3.
After confirmation and adjustment of Tension Post
position (Refer to item 1-2), load the cassette type
torque tape and set to the PLAY mode.
Confirm that the right meter of the torque tape indicates
60~110gf•cm during playback in SP mode.
Confirm that the left meter of the torque tape indicates
25~40gf•cm during playback in SP mode.
Tentelometer
Video Tape
Guide Roller
P1 Post
Fig. 1-3
CONFIRMATION AND ADJUSTMENT OF REEL
DISK HEIGHT
1-1:
1.
2.
3.
4.
Turn on the power and set to the STOP mode.
Set the master plane and reel disk height adjustment jig
on the mechanism framework, taking care not to scratch
the drum, as shown in Fig. 1-1-A.
Confirm that "A" of the reel disk is lower than "B" of the
reel disk height adjustment jig , and is higher than "C". If
it is not enough height, adjust to 10(+0.2, -0) mm with
the height adjustment washer.
Adjust the other reel in the same way.
1-2: CONFIRMATION AND ADJUSTMENT OF TENSION
POST POSITION
1.
2.
3.
Set to the PLAY mode.
Adjust the Tension Adjust until the edge of the Tension
Arm is positioning within 0.5mm range from the
standard line center of Main Chassis.
After this adjustment, confirm that the cut position is
located in "A" area as shown in Fig. 1-2-B. If it is
located in "B" area, adjust again.
While turning the S Reel clockwise, confirm that the
edge of the Tension Arm is located in the position
described above.
Fig. 1-2-A
Standard line of Main Chassis
Tension Adjust
Tension Arm
0.5mm (Adjusting range)
Standard line center of Main Chassis
(A)
Cut Position
Fig. 1-2-B
(B)
Tension Adjust
Fig. 1-1-A
Reel Disk
Height Adjustment
Washer
2.6x4.7xT0.13
2.6X4.7xT0.25
(B)
(C)
Fig. 1-1-B
(A)
10(+0.2, -0)mm
Master Plane
Reel Disk Height Adjustment Jig
Master Plane
Reel Disk Height
Adjustment Jig
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