JVC AV-20FA44/SA, AV-N21A44/SA Service Manual
SERVICE MANUAL
COLOR TELEVISION
5216620039
AV-20FA44/SA,
AV-N21A44
/SA
BASIC CHASSIS
FJ
POWER
TV
DVD
CATVVCR
INPUT
DISPLAY
1
3
2
SLEEP TIMER
4
6
5
SOUND
7
9
8
RETURN+
100+
VIDEO STATUS
0
THEATER PRO
LIGHT
ASPECT
MUTING
C.C.
CH +
VOL
VOL
+
Ð
CH Ð
EXIT
MENU
VCR/DVD
VCR CHANNEL
TV/VCR
POWER
PREV NEXT
PLAY FFREW
REC
STOP PAUSE
OPEN/CLOSE
STILL/PAUSE
------------------
TV
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
2 SPECIFIC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29
COPYRIGHT © 2003 VICTOR COMPANY OF JAPAN, LIMITED
No.52166
2003/9
SPECIFICATION
Items Contents
Dimensions ( W × H × D ) 66.7cm × 47.7cm × 50.5cm (26-1/4" × 18-13/16" × 19-7/8")
Mass 25kg (55lbs)
TV RF System CCIR(M)
Color System NTSC
Sound System BTSC (Multi Channel Sound)
TV Receiving Channels
and Frequency
TV / CATV Total Channel 180 Channels
Intermediate Frequency Video IF
Color Sub Carrier 3.58 MHz
Power Input AC120V , 60Hz
Power Consumption 75W
Picture Tube 20" (51cm) Measured diagonally, full square (H:40.6cm × V:30.5cm)
High Voltage 26.0kV ±1.3kV (at zero beam current)
Speaker 6.5cm × 13cm (2-1/2" × 5"), Oval type × 2
Audio Output 3W + 3W
Antenna Terminal (VHF/UHF) F-type connector, 75Ω unbalanced, coaxial
Video / Audio Input (1/2/3) Video
Component video
Audio Output (Fix) 0.5V(rms)(-4dBs), low impedance (400Hz when modulated 100%)
Headphone Jack 3.5mm mini jack × 1
Remote Control Unit RM-C1251G (AA/R06 dry battery × 2)
Design & specifications are subject to change without notice.
VHF Low
VHF High
UHF
CATV
Sound IF
Audio
S-Video
[INPUT-1]
[INPUT-2]
02ch~06ch : 54MHz~88MHz
07ch~13ch : 174MHz~216MHz
14ch~69ch : 470MHz~806MHz
54MHz~804MHz
Low Band : 02~06, A-8 by 02~06&01
High Band : 07~13 by 07~13
Mid Band : A~I by 14~22
Super Band : J~W by 23~36
Hyper Band : W+1~W+28 by 37~64
Ultra Band : W+29~W+84 by 65~125
Sub Mid Band : A8, A4~A1 by 01, 96~99
45.75 MHz
41.25 MHz (4.5MHz)
1V(p-p), 75Ω (RCA pin jack × 3)
0.5V(rms) (-4dBs), high impedance (RCA pin jack × 6)
Mini-DIN 4pin× 1
Y : 1V(p-p) positive (negative sync), 75Ω
C : 0.286V(p-p) (burst signal), 75Ω
RCA pin jack × 3
Y : 1V(p-p) positive (negative sync), 75Ω
PB/PR : 0.7V(p-p), 75Ω
(RCA pin jack × 2)
1-2 (No.52166)
SECTION 1
PRECAUTION
1.1 SAFETY PRECAUTIONS
(1) The design of this product contains special hardware, 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. Service should be performed by qualified personnel only.
(2) Alterations of the design or cir cuitry of the pr oducts shou ld n ot be
made. Any design alterations or additions will void the
manufacturer's warranty and will further relieve the manufacturer
of responsibility for personal injury or property damage resulting
therefrom.
(3) Many electrical and me chanical 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 w hich 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 Service manual. The use of a substitute replacement
which does not have the same safety characteristics as the
recommended replacement part shown in the part s list of Service
manual may cause shock, fire, or other hazards.
(4) Use isolation transformer when hot chassis.
The chassis and any sub-chassis contained in some products are
connected to one side of the AC power line. An isolation
transformer of adequate capacity should be inserted between the
product and the AC power supply point while performing any
service on some products when the HOT chassis is exposed.
(5) Don't short between the LIVE side ground and ISOLATED
(NEUTRAL) side ground or EARTH side ground whe n repairing.
Some model's power circuit is partly different in the GND. The
difference of the GND is shown by the LIVE : ( ) side GND, the
ISOLATED (NEUTRAL) : ( ) side GND and EARTH : ( ) side
GND.
Don't short between the LIVE side GND and ISOLATED (NEUTRAL)
side GND or EARTH side GND and never measu re the LIVE side
GND and ISOLATED (NEUTRAL) side GND or EARTH side GND at
the same time with a measuring apparatus (oscilloscope etc.). If
above note will not be kept, a fuse or any parts will be broken.
(6) If any repair has been made to the chassis, it is recommended that
the B1 setting should be checked or adjusted (See B1 POWER
SUPPLY check).
(7) The high voltage applied to the picture tube must conform with that
specified in Service manual. Excessive high voltage can cause an
increase in X-Ray emission, arcing and possible component
damage, therefore operation under excessive high voltage
conditions should be kept to a minimum, or should be prevented.
If severe arcing occurs, remove the AC power immediately and
determine the cause by visual inspection (incorrect installation,
cracked or melted high voltage harness, poor soldering, etc.). To
maintain the proper minimum level of soft X-Ray emission,
components in the high voltage circuitry including the picture tube
must be the exact replacements or alternatives approved by the
manufacturer of the complete product.
(8) Do not check high voltage by drawing an arc. Use a high voltage
meter or a high voltage probe with a VTVM. Discharge the picture
tube before attempting meter connection, by connecting a clip lead
to the ground frame and connecting the other end of the lead
through a 10kΩ 2W resistor to the anode button.
(9) When service is required, observe the original lea d dress. Extra
precaution should be given to assure correct lead dress in the high
voltage circuit area. Where a short circuit has occurred, those
components that indicate evidence of overheating should be
replaced. Always use the manufacturer's replacement
components.
(10) Isolation Check (Safety fo r Electrical Shock Hazard)
After re-assembling the product, always perform an isolation
check on the exposed metal parts of the cabinet (antenna
terminals, video/audio input and output terminals, Control knobs,
metal cabinet, screw heads, earphone jack, control shafts, etc.) to
be sure the product is safe to operate without danger of electrical
shock.
a) Dielectric Strength Test
The isolation between the AC primary circuit and all metal parts
exposed to the user, particularly any exposed metal part having a
return path to the chassis should withstand a voltage of 1100V AC
(r.m.s.) for a period of one second.
(. . . . Withstand a voltage of 1100V AC (r.m.s.) to an appliance
rated up to 120V, and 3000V AC (r.m.s.) to an appliance rated
200V or more, for a period of one second.) This method of test
requires a test equipment not generally found in the service trade.
b) Leakage Current Check
Plug the AC line cord directly into the AC outlet (do not use a line
isolation transformer during this check.). Using a "Leakage Current
Tester", measure the leakage current from each exposed metal part
of the cabinet, particu larly any ex posed meta l part having a return
path to the chassis, to a known good earth ground (water pipe, etc.).
Any leakage current must not exceed 0.5mA AC (r.m.s.).
However, in tropical area, this must not exceed 0.2mA AC (r.m.s.).
Alternate Check Method
Plug the AC line cord directly into the AC outlet (do not use a
line isolation transformer during this check.). Use an AC
voltmeter having 1000Ω per volt or more sensitivity in the
following manner. Connect a 1500Ω 10W resistor paralleled by
a 0.15µF AC-type capacitor between an exposed metal part and
a known good earth ground (water pipe, etc.). 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. Any
voltage measured must not exceed 0.75V AC (r.m.s.). This
corresponds to 0.5mA AC (r.m.s.).
However, in tropical area, this must not exceed 0.3V AC
(r.m.s.). This corresponds to 0.2mA AC (r.m.s.).
AC VOLTMETER
(HAVING 1000 /V,
OR MORE SENSITIVITY)
0.15 F AC-TYPE
PLACE THIS PROBE
1500 10W
(11) High voltage hold down circuit check.
GOOD EARTH GROUND
ON EACH EXPOSED
METAL PART
After repair of the high voltage hold down circuit, this circuit shall
be checked to operate correctly.See item "How to check the high
voltage hold down circuit".
This mark shows a fast
operating fuse, the
letters indicated below
show the rating.
A V
POWER CORD
REPLACEMENT WARNING.
Connecting the white line side of power
cord to "WHT" character side.
PWB
White line side
WHT
PW
(No.52166)1-3
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
2.1 FEATURES FLAT SQUARE CRT
It became legible from any position by CRT with few reflection and reflect lumps on the flat screen.
DIGITAL COMB FILTER
By the three-line digital comb filter, the refreshed image can be seen.
VIDEO STATUS
Expression of a favorite screen can be choosen by the VIDEO STATUS function. (STANDARD, THEATER, DYNAMIC, GAME)
COMPONENT VIDEO INPUT TERMINAL
Since the component video input terminal is equipped, it reappears direct without deterriorating the signal from DVD or Video player.
BBE
Because build in the BBE circuit, improved the sound of conversation.
MTS STEREO SYSTEM
The voice multiplex function of the MTS system is built in. (MTS = Multi channel Television Sound system)
TELETEXT (CLOSED CAPTION)
Title TELETEXT broadcast of C1~C4 and T1~T4 formula is receivable.
V-CHIP
Since the V Chip is built in, it can choose, view and listen to a healthy program.
ON / OFF TIMER
The on/off timer lets you program your television to turn itself on or off. You can use it as an alarm to wake up, to help you remember
important programs, or as a decoy when you're not home.
HYPER SCAN
A quick favorite program can be looked for by the HYPER-SCAN function.
2.2 MAIN DIFFERENCE LIST Item AV-20FA44/SA AV-N21A44/SA
MAIN PWB SFJ-1001A-M2 SFJ-1002A-M2
FRONT CABI ASSY GQ10063-001B-A GQ10063-002B-A
RATING LABEL GQ30032-001A-A GQ20001-001A-A
A.H.S Available --V-CHIP Available ---
1-4 (No.52166)
2.3 FUNCTIONS
FRONT PANEL
REAR TERMINAL
INPUT 3
VIDEO L MONO AUDIO R
INPUT 1 INPUT 2
MENU CHANNEL VOLUME
OPERATE
INPUT-3 VIDEO
INPUT-3 AUDIO L
INPUT-3 AUDIO R
MENU key
CHANNEL-/+, OPERATE / keys
VOLUME -/+ keys
AUDIO
L/MONOL/MONO
COMPONENT
VIDEO
VIDEO/Y
P
B
PR
S-VIDEO
OVER
VIDEO
AUDIO OUT
L
RRR
REMOTE CONTROL UNIT (RM-C1251)
TV
CATV VCR
INPUT
DISPLAY
SLEEP TIMER
SOUND
VIDEO STATUS
THEATER PRO
MUTING
VOL
-
MENU
VCR CHANNEL
PREV NEXT
REC
OPEN/CLOSE
ASPECT
POWER
DVD
1
2
4
5
7
8
100+
0
CH +
CH -
VCR/DVD
POWER
PLAY FFREW
STOP PAUSE
STILL/PAUSE
LIGHT
C.C.
VOL
EXIT
TV/VCR
3
6
9
RETURN+
+
75
(VHF/UHF)
AUDIO OUTPUT (L, R)
INPUT-1 (VIDEO, L/MONO, R)
INPUT-1 (S-VIDEO)
INPUT-2 (L/MONO, R)
INPUT-2 (VIDEO/Y, PB, PR)
Antenna terminal (VHF/UHF)
TV/CATV switch
VCR/DVD switch
INPUT key
DISPLAY key
SLEEP TIMER key
SOUND key
VIDEO STATUS key
THEATER PRO key
ASPECT key
MUTING key
VOLUME(-/+) keys
MENU key
POWER key
Channel number keys
LIGHT key
C.C. key
CHANNEL(-/+) keys
EXIT key
VCR/DVD operate keys
RM-C1251G
TV
(No.52166)1-5
SECTION 3
DISASSEMBLY
3.1 DISASSEMBLY PROCEDURE
3.1.1 REMOVING THE REAR COVER
(1) Unplug the power plug.
(2) Remove the 7 screws [A] as shown in the Fig.1.
(3) Remove the 4 screws [B] as shown in the Fig.1.
(4) Withdraw the REAR COVER toward you.
3.1.2 REMOVING THE MAIN PWB
• Remove the REAR COVER.
(1) Raise the backside of the MAIN PWB, and remove the
PWB STOPPER [C] from the cabinet.
(2) Withdraw the MAIN PWB backward. (If necessary, remove
the wire clamp, connectors etc.)
3.1.3 REMOVING THE SPEAKER
• Remove the REAR COVER.
(1) Remove the 2 screws [D], then remove the SPEAKER with
spacer, as shown in Fig.1.
(2) Remove the 4 screws [E] to detach the SPEAKER from
spacer.
(3) Follow the same steps when remove the other hand
SPEAKER.
NOTE:
When removing the 2 screws [D] of the SPEAKER, remove the
lower side screw first, and then remove the upper one.
3.1.4 CHECKING THE PW BOARD
• To check the back side of the PW Board.
(1) Pull out the PW Board . (Refer to REMOVING THE MAIN
PWB).
(2) Erect the PW Board vertically so that you can easily check
the back side of the PW Board.
3.1.5 CAUTION
(1) When erecting the PW Board, be careful so that there will
be no contacting with other PW Board.
(2) Before turning on power, make sure that the wire connector
is properly connected.
(3) When conducting a check with power supplied , be sure to
confirm that the CRT EARTH WIRE (BRAIDED ASS'Y) is
connected to the CRT SOCKET PW board.
3.1.6 WIRE CLAMPING AND CABLE TYING
(1) Be sure to clamp the wire.
(2) Never remove the cable tie used for tying the wires together.
Should it be inadvertently removed, be sure to tie the wires
with a new cable tie.
1-6 (No.52166)
FRONT CABINET
E
SPEAKER
SPEAKER
HOLDER
CRT SOCKET PWB
SPACER
D
HVT
REAR COVER
MAIN PWB
C
(PWB STOPPER)
POWER CORD
Fig.1
B
A
(No.52166)1-7
3.2 REPLACEMENT OF MEMORY IC
3.2.1 MEMORY IC
This model use a memory IC. This memory IC stores data for proper operation of the video and de flection circuits.
When replacing, be sure to use an IC containing this (initial value) data.
3.2.2 PROCEDURE FOR REPLACING MEMORY IC
1. Power off
Switch the power off and unplug the power cord from the
SERVICE MENU
outlet
2. Replace IC.
Be sure to use memory IC written with the initial data values.
3. Power on
Plug the power cord into the outlet and switch the power on.
1.V/C(S)
3.SOUND(A)
7.LOW LIGHT
9.VCO
11.I2C BUS
2.DEF(D)
4.OT HERS(F)
8.HIGH LIGHT
4. User settings
Check the user setting items according to after page.
Where these do not agree, refer to the OPERATING
INSTRUCTIONS (USER'S GUIDE) and set the items as
described.
5. Receive channel setting
Refer to the OPERATING INSTRUCTIONS (USER'S
GUIDE) and set the receive channels (Channels Preset) as
described.
6.SERVICE MENU setting
Verify what to set in the SERVICE MENU, and set whatever
is necessary. Refer to the ADJUSTMENT for setting.
Before entering the SERVICE MENU, confirm that the
setting of TV / CATV SW of the REMOTE CONTROL UNIT
is at the "TV" side and the setting of VCR / DVD SW is at the
"VCR" side. If the switches have not been properly set, you
cannot enter the SERVICE MENU.
(1) Press [SLEEP TIMER] key and while the indication of
SLEEP TIMER 0 MIN is being displayed, press
[DISPLAY] key and [VIDEO STATUS] key on the
remote control unit (Fig.2) simultaneously.
(2) The SERVICE MENU screen as shown in Fig.1 is
displayed.
(3) Verify what to set in the SERVICE MENU, and set
whatever is necessary (Fig.1).
Refer to the SERVICE ADJUSTMENT for setting.
(4) Press the [EXIT] key twice to return normal screen.
SELECT BY
OPERATE BY
TV/CATV SW
DISPLAY
SLEEP TIMER
VIDEO STATUS
VOLUME - / +
TV
CATV VCR
INPUT
DISPLAY
SLEEP TIMER
SOUND
VIDEO STATUS
THEATER PRO
MUTING
VOL
MENU
-
Fig.1
DVD
1
4
7
100+
ASPECT
CH +
CH -
Fig.2
POWER
2
5
8
0
RETURN+
LIGHT
C.C.
VOL
+
EXIT
EXIT BY
3
6
9
EX IT
VCR/DVD SW
CHANNEL - / +
EXIT
1-8 (No.52166)
3.3 FACTORY SHIPPING VALUES
3.3.1 SETTING OF REMOTE CONTROL UNIT
Setting item Setting value Setting item Setting value
POWER Off DISPLAY ON
CHANNEL CH - 02 VIDEO STATUS DYNAMIC
VOLUME 10 ASPECT 4:3
TV / VIDEO TV
3.3.2 SETTING OF MENU SCREEN
Setting item Setting value Setting item Setting value
PICTURE MODE CLOCK / TIMER MODE
TINT Center SET CLOCK OFF
COLOR Center ON TIME 7:00 PM
PICTURE Center OFF TIME 10:00 PM
BRIGHT Center CHANNEL 02
DETAIL Center ON VOLUME CURRENT
COLOR TEMPERATURE HIGH MODE EVERY DAY
NOISE MUTING ON ON/OFF TIMER OFF
VSM OFF INITIAL SETUP MODE
SOUND MODE LANGUAGE ENG [AV-20FA44]
BASS Center SPA [AV-N21A44]
TREBLE Center FRONT PANEL LOCK OFF
BALANCE Center AUTO SHUT OFF OFF
MTS STEREO CLOSED CAPTION OFF
A.H.S [AV-20FA44] OFF AUTO TUNER SETUP CABLE
BBE ON V - CHIP [AV-20FA44] OFF
SET LOCK CODE (0000)
XDS ID [AV-20FA44] ON
(No.52166)1-9
Loading...