JVC AV-21VT14P User manual

SERVICE MANUAL
COPYRIGHT © 2004 Victor Company of Japan, Limited No.YA140
2004/9
FLAT COLOUR TELEVISION
YA14020049
AV-21VT14/P,
AV-21VT34/P
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30
BASIC CHASSIS
CW

1-2 (No.YA140)
SPECIFICATION
Design & specifications are subject to change without notice.
Items Contents
AV-21VT14/P AV-21VT34/P
Dimensions (W ×H ×D) 64.9cm ×46.55cm ×47.35cm
Mass 24kg 26.4kg
TV RF System M
Colour System TV Mode
Video Mode
NTSC3.58
PAL / SECAM / NTSC3.58 / NTSC4.43
Stereo System MTS (Multi-Channel Television Sound)
Receiving Frequency VHF Low
VHF High
UHF
CATV
46.25MHz ~ 168.25MHz (AU0 ~ S10)
175.25MHz ~ 463.25MHz (E5 ~ S41)
471.25MHz ~ 863.25MHz (E21 ~ CHINA 57)
Mid : X ~ Z, S1 ~ S10
Super: S11 ~ S20
Hyper: S21 ~ S41
Intermediate
Frequency
VIF 38.0MHz
SIF 33.5MHz (4.5MHz)
Colour Sub Carrier Frequency 4.43MHz (PAL), 4.40MHz/4.25MHz (SECAM), 3.58MHz/4.43MHz (NTSC)
Aerial Input Terminal 75Ωunbalanced, coaxial
Power Input AC110V-AC240V, 50Hz / 60Hz
Power Consumption 121W (Max.) / 81W (Avg.) 143W (Max.) / 91W (Avg.)
Picture Tube A51LVV896X
21-inch, aspect ratio 4:3, flat square face type, tinted
Screen Size Visible size :51.0cm (Diagonal) / 41.6cm ×31.5cm (H ×V)
High Voltage 29kV ± 1.5kV (at zero beam current)
Speaker 6.5cm ×13cm, Oval type ×26.5cm×13cm, oval type ×2
13cm, round type ×1 (Bass blaster unit)
Audio Output 7W + 7W 7W + 7W + 13W
Video / Audio Input
[1/2/3]
S-Video [1] Mini-DIN 4 pin ×1
Y: 1V(p-p), positive (negative sync provided), 75Ω
C: 0.286V(p-p) (Burst signal), 75Ω
Video [1/2/3] 1V(p-p), negative sync, 75Ω, RCA pin jack ×3
Audio [1/2/3] 500mV(rms) (-4dBs ), high impedance, RCA pin jack ×6
Component
Video [2]
RCA pin jack ×3
Y:1V(p-p), positive (negative sync), 75Ω
Cb/Cr:0.7V(p-p), 75Ω
Video / Audio Output Video
Audio
1V(p-p), 75Ω, RCA pin jack ×1
500mV(rms)(-4dBs), Low impedance (400Hz when modulated 100%), RCA pin jack ×2
Headphone 3.5mm stereo mini jack ×1
Remote Control Unit RM-C1282-2H
(AA/R06/UM-3 battery ×2)

(No.YA140)1-3
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 circuitry of the products should
not 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 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 Service
manual. The use of a substitute replacement which does
not have the same safety characteristics as the
recommended replacement part shown in the parts list of
Service manual may cause shock, fire, or other hazards.
(4) Don't short between the LIVE side ground and
ISOLATED (NEUTRAL) side ground or EARTH side
ground when 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
measure 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.
(5) 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).
(6) 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.
(7) 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.
(8) When service is required, observe the original lead 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.
(9) Isolation Check (Safety for 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 3000V 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, particularly
any exposed metal 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 1000Ωper 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)
PLACE THIS PROBE
ON EACH EXPOSED
METAL PART
1500 10W
0.15 F AC-TYPE
GOOD EARTH GROUND

1-4 (No.YA140)
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
2.1 FEATURES
• New chassis design enables use of an interactive on-screen control.
• Pure flat CRT produces fine textured picture in every detail.
• Wide range voltage (110V ~ 240V) for AC power input.
• With AUDIO/VIDEO/S-VIDEO/COMPONENT input terminals.
•I
2C bus control utilizes single chip ICs.
• By means of AUTO PROGRAM, the TV stations can be selected automatically and the TV channels can also be rearranged
automatically.
• Built-in DIGITAL ECO MODE (ECONOMY, ECOLOGY).
In accordance with the brightness in a room, the brightness and/or contrast of the picture can be adjusted automatically to make the
optimum picture which is easy on the eye.
• Built-in OFF TIMER & RETURN +.
2.2 MAIN DIFFERENCE LIST
Items AV-21VT14/P AV-21VT34/P
BASS BLASTER None BASS BLASTER UNIT
AUDIO OUTPUT 7W + 7W 7W + 7W + 13W
POWER CONSUMPTION 121W (Max.) / 81W (Avg.) 143W (Max.) / 91W (Avg.)

(No.YA140)1-5
2.3 FUNCTIONS
REMOTE CONTROL UNIT
RM-C1282-2H
FRONT PANEL CONTROLS
1
2
3
4
5
6
7
8
9
10
11
COLOUR SYSTEM key
FAVORITE CHANNEL keys
DISPLAY BACK key
CLOSED CAPTION key
SOUND TURBO key
PICTURE MODE key
RETURN + key
OFF TIMER key
CHANNEL (-/+) keys
Not used
12
13
14
15
16
17
18
19
20
21
ECO key
POWER key
TV / VIDEO key
MENU (OK) key
MUTING key
Number keys
100+ key
VOLUME (-/+) keys
BASS key [AV-21VT34/P]
CINEMA SURROUND key
1
2
3
5
6
7
8
9
10
11
12
4
13
14
16
18
17
21
19
20
15
MENU ( / , / ) keys
1
2
3
4
5
6
7
8
9
10
11
IN (VIDEO-3) : VIDEO
HEADPHONE jack
IN (VIDEO-3) : AUDIO L/MONO
IN (VIDEO-3) : AUDIO R
MENU (OK) button
CHANNEL (-/+) buttons
VOLUME (-/+) buttons
Remote control sensor
ECO sensor
POWER lamp
MAIN POWER button
IN (VIDEO-3)
V R
L / MONO
POWER
OK
CHANNEL VOLUME
MENU
321 4 6 7 8 9 10 11
5

1-6 (No.YA140)
REAR TERMINAL
[AV-21VT14/P]
[AV-2VT34/P]
2
3
4
5
6
7
8
9
10
11
12
1313
VIDEO-1 INPUT TERMINAL
S-VIDEO
VIDEO
AUDIO L/MONO
AUDIO R
COMPONENT (VIDEO-2) INPUT TERMINAL
Y/VIDEO
C
B
C R
AUDIO L/MONO
AUDIO R
OUTPUT TERMINAL
VIDEO
AUDIO L
AUDIO R
Aerial input terminal
1
V
L
RR
L/MONO
Y
C
B
C R
/V
V
S
OVER
L
R
/MONO
OUTPUT
VIDEO-1 COMPONENT
(VIDEO-2)
INPUT
INPUT
7
4
3
212
1
9
5 6 10 118
13
2
3
4
5
6
7
8
9
10
11
12
14
VIDEO-1 INPUT TERMINAL
S-VIDEO
VIDEO
AUDIO L/MONO
AUDIO R
COMPONENT (VIDEO-2) INPUT TERMINAL
Y/VIDEO
C
B
C R
AUDIO L/MONO
AUDIO R
OUTPUT TERMINAL
VIDEO
AUDIO L
AUDIO R
BASS BLASTER UNIT OUTPUT TERMINAL
BASS SPEAKER OUT
Aerial input terminal
1
13
V
L
RR
L/MONO
Y
C
B
C R
/V
V
S
OVER
L
R
/MONO
BASS
SPEAKER
OUT
OUTPUT
VIDEO-1 COMPONENT
(VIDEO-2)
INPUT
INPUT
7
4
3
13
2
12 14
1
9
5 6 10 118

(No.YA140)1-7
2.4 MAIN CPU [MAIN PWB : IC701] PIN FUNCTION
Pin no. Pin name I/O Remark
1VssP2 -GND
2 VssC4 - GND
3 V1.8C4 I 1.8V (Digital)
4 V3.3A3 I 3.3V
5 VrefP_Sdac I 3.3V (Positive)
6 VrefN_Sdac - GND
7 VrefP_Sdac I 3.3V (Negative)
8 VrefN_Sdac - GND
9 VrefP_Sdac I 3.3V (Positive)
10 XtalIn I 24.567MHz for system clock
11 XtalOut O 24.567MHz for system clock
12 VssA1 - GND
13 NECK I V-guard input/ I/O switch
14 CONT I 1.8V regulator control
15 V5P1 I +5V
16 Ph2 - Phase-2 filter
17 Ph1 - Phase-1 filter
18 Gnd1 - GND
19 SecPll - SECAM PLL decoupling
20 Dec8G - Bandgap decoupling
21 EW O East-West drive output
22 VDRB- O Vertical drive B output
23 VDRA+ O Vertical drive A output
24 Vif1 I Video IF input 1
25 Vif2 I Video IF input 2
26 Vsc - Vertical sawtooth capacitor
27 Iref I Reference current input
28 GndIF - GND
29 Sif1 I Sound IF input 1
30 Sif2 I Sound IF input 2
31 AGC O Tuner AGC output
32 EHT I EHT/overvoltage protection input
33 Ssif/RefIn/Avl/RefOut O
Automatic Volume Levelling/ sound IF input /
subcarrier reference output / external reference
signal input for I signal mixer for DVB operation
34 L3 I Audio-L3 input (left signal)
35 R3 I Audio-R3 input (right signal)
36 L_OUT O Audio L output
37 R_OUT O Audio R output
38 DecsDem - Decoupling sound demodulator
39 QssO/AmO/AudeEm O QSS intercarrier output / AM output /
deemphasis / (front-end audio out)
40 Gnd2 - GND
41 PllIf - IF-PLL loop filter
42 SifAgc - AGC sound IF
43 IfVo/FmRo/DvbO O Not used
44 NC O Not used
45 V8AudioSwitches I 8V
46 AgcSsif - AGC capacitor second sound IF
47 V5P2 I 5V
48 V_OUT O Video output
49 L1 I Audio-L1 input
50 R1 I Audio-R1 input
51 V3 I Video V3 input
52 C4 I Not used
53 Audio2InL I Not used
54 Audio2InR I Not used
55 V2/Y I Video 2 input
56 L2 I Audio L2 input (Left signal)
57 R2 I Audio R2 input (right signal)
58 Y3/Cvbs I S-Video Y1 input
59 C1 I S-Video C1 input
60 AudioLsL O Audio L output for audio power amplifier
61 AudioLsR O Audio R output for audio power amplifier
62 HP_L O Headphone L
63 HP_R O Headphone R
64 CVBSO/PIP O CVBS / PIP output
65 SVM O Scan velocity modulation output
66 FbiSo I Flyback input/sandcastle output
67 Hout O Horizontal output
68 VssComb - GND
69 V5Comb I 5V
70 Vin/R2/Pr I PIP R input
71 Uin/B2/Pb I PIP B input
72 Yin/G2/Y I PIP G input
73 Ysync I Not used
74 Yout O Not used
75 Uout/INSSW2 I YUV insertion input
76 NC O Not used
77 INSSW3 I YUV insertion input
78 R3/Pr I Component PR input (Video-2)
79 G3/Y I Component Y input (Video-2)
80 B3/Pb I Component PB input (Video-2)
81 Gnd3 - GND
82 V5P3 I 5V
83 BCL I Beam current limiter input
84 BLKIN I Black current input
85 Rout O R output
86 Gout O G output
87 Bout O B output
88 V3.3A1 I 3.3V
89 RefAdN - GND
90 V3.3RefAdP I 3.3V (Positive)
91 RefAd I 3.3/2V
92 GndA - GND
93 V1.8A I 1.8V
94 V3.3A2 I 3.3V
95 VssADC - GND
96 V1.8ADC I 1.8V
97 REMOTE I Remote control
98 PW_LED I POWER LED control
99 P11/TO I POWER LED control
100 V1.8C2 I 1.8V
101 VssC2 - GND
102 COMPONENT-PIP - Not used
103
COMB_SW_NT3.5/OTHER - Not used
104 VER_PROTECT O X-ray protect
105 S_REDUCE O Sound control
106 P00/I2SDI1 O Not used
107 POWER O SUB POWER control
108 SCL1 I I2C bus clock
109 SDA1 I/O I2C bus clock
110 V3.3P I 3.3V
111 ROTATION O ROTATION
112 3.58/OTHER O NTSC 3.58 detection
113 A_MUTE O Audio muting
114 4.5/OTHER O NTSC 4.43 detection
115 PROT I Protect
116 ECO_IN I ECO sensor level detection
117 V1.8C1 I 1.8V (Digital)
118 DecV1V8 I 1.8V
119 KEY_IN I Key scan data
120 VDO_DET I Video DET input
121 VSSC1+P1 - Digital GND
122 P24/PWM3 I S-Video DET input
123 P25/PWM4 O GTVA_reset
124 V1.8C3 I 1.8V (Digital)
125 VssC3 - GND
126 P12/Int2 I External interrupt
127 SDA0 I/O I2C bus data (for memory)
128 SCL0 I I2C bus clock (for memory)
Pin no. Pin name I/O Remark

1-8 (No.YA140)
SECTION 3
DISASSEMBLY
3.1 DISASSEMBLY PROCEDURE
3.1.1 REMOVING THE TWIN PORT BASS BLASTER UNIT
[AV-21VT34/P]
• Unplug the power supply cord.
(1) Disconnect the TWIN PORT BASS BLASTER UNIT’s cord
from the rear of the TV set.
(2) Remove the TWIN PORT BASS BLASTER UNIT by pulling
it upwards.
NOTE:
After removing the TWIN PORT BASS BLASTER UNIT,
proceed to the following procedure.
3.1.2 REMOVING THE REAR COVER
• Unplug the power cord.
(1) Remove the 9 screws [A] and 4 screws [B] as shown in
Fig.1.
(2) Withdraw the REAR COVER toward you.
CAUTION:
When reinstalling the rear cover, carefully push it inward after
inserting the MAIN PWB into the REAR COVER groove.
3.1.3 REMOVING THE MAIN PW BOARD
• Remove the REAR COVER.
(1) Slightly raise the both sides of the MAIN PWB by hand.
(2) Withdraw the MAIN PWB backward.
(If necessary, take off the wire clamp and connectors, etc.)
3.1.4 REMOVING THE SPEAKER
• Remove the REAR COVER.
(1) Remove the 2 screws [C] as shown in Fig.1.
(2) Follow the same steps when removing the other hand
SPEAKER.
3.1.5 CHECKING THE MAIN PW BOARD
• To check the back side of the MAIN PWB.
(1) Pull out the MAIN PWB. (Refer to REMOVING THE MAIN
PW BOARD).
(2) Erect the MAIN PWB vertically so that you can easily check
its back side.
CAUTIONS:
• Before turning on power, make sure that the CRT earth wire
and other connectors are properly connected.
• When repairing, connect the DEG. COIL to the DEG.
connector on the MAIN PWB.
• When repairing, connect the DEG. COIL to the DEG.
connector on the MAIN PWB.
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.

(No.YA140)1-9
Fig.1
BASS SPEAKER OUT JACK
[AV-21VT34/P]
TWIN PORT
BASS BLASTER UNIT
[AV-21VT34/P]
PICTURE TUBE
FRONT CABINET
MAIN PWB
FBT
MAIN PWB
(CRT SOCKET PWB)
REAR COVER
A
B
C
C
SPEAKER
SPEAKER
(x4)
(x9)
(x2)
(x2)

1-10 (No.YA140)
3.2 REPLACEMENT OF MEMORY IC
3.2.1 MEMORY IC
This TV uses the following memory IC.
Memory IC: IC702 on MAIN PWB
The memory IC memorizes data for correctly operating the video
and deflection circuits. When replacing the memory IC, be sure
to use the same type IC written with the initial values of data. In
other words, use the specific IC listed in "PRINTED WIRING
BOARD PARTS LIST". For its mounting location, refer to
"ADJUSTMENT LOCATIONS".
3.2.2 PROCEDURE FOR REPLACING MEMORY IC
1. Power off
Switch the power off and unplug the power cord from the wall
outlet.
2. Replacing the memory IC
Replace the memory IC with new one. Be sure to use the
memory IC written with the initial data values.
3. Power on
Plug the power cord into the wall outlet and switch the power on.
4. Check and setting of SYSTEM CONSTANT SET:
(1) Press the [DISPLAY] key and the [PICTURE MODE] key
on the remote control unit simultaneously.
The SERVICE MENU screen will be displayed.(See
Fig.1.)
(2) In the SERVICE MENU, press the [DISPLAY] key and
[PICTURE MODE] key simultaneously. Then, the
SYSTEM CONSTANT SET screen will be
displayed.(See Fig.2.)
(3) Check whether the setting values of the SYSTEM
CONSTANT SET are the same as those indicated in
Table 1.
If the value is different, select the setting item with the
MENU [] / [] key, and set the correct value with the
MENU [] / [] key.
(4) Press the [DISPLAY] key twice to return to the normal
screen.
5. Receive channel setting
Refer to the OPERATING INSTRUCTIONS and set the
receive channels (channels preset).
6. User setting
Check the user setting values in Table 2 and Table 3. If setting
value is different, set the correct value.
For setting, refer to the OPERATING INSTRUCTIONS.
7. Setting of SERVICE MENU
Verify the setting for each setting item in the SERVICE
MENU.(See Table 4.) If readjustment is necessary, perform
adjustment referring to "ADJUSTMENTS PROCEDURE".
Fig.1
Fig.2
DISPLAY / BACK
NAME OF REMOTE CONTROL KEYS
MENU
MENU
MENU
MENU
PICTURE
MODE
1. IF
3. AUDIO
5. VSM W/B
7. PLUG & PLAY (ON)
2. V/C
4. DEF
6. S TATUS
SERVICE MENU
1-7 : SELECT DISPLAY : EXIT
SERVICE MENU
******* **** ***** *****
**** **** *** ***
SYSTEM CONSTANT-1
: SEL  : OPE
COMB
TILT NO
NO
SUPER BASS NO
SYSTEM CONSTANT
SYSTEM OTHERS
SET 1
DISP : EXIT
SYSTEM CONSTANT-2
: SEL  : OPE
BLUE BACK MUTE
STEREO
NO
ECO SENSOR YES
SYSTEM CONSTANT SET 2
SOUND
DISP : EXIT
SYSTEM CONSTANT-3
: SEL  : OPE
YES
SYSTEM CONSTANT SET 3
SURROUND
NOPICTURE BOOSTER
YESCOMPONENT
YESS INPUT
DISP : EXIT

(No.YA140)1-11
3.2.3 FACTORY SETTING VALUE
SETTING OF SYSTEM CONSTANT SET
Table 1
COMB NO
TILT NO
NO
SUPER BASS YES
SOUND STEREO
BLUE BACK MUTE NO
ECO SENSOR YES
SURROUND YES
PICTURE BOOSTER NO
COMPONENT YES
S INPUT YES
Setting item Setting content Setting
AV-21VT14/P AV-21VT34/P
value
YES NO
SYSEM OTHERS
TAIWAN OTHERS
YES NO
YES NO
YES NO
YES NO
STEREO PB MONO
YES NO
YES NO
YES NO
YES NO

1-12 (No.YA140)
SETTING OF BASIC FUNCTIONS
Table 2
SETTING OF MENU SCREEN
Table 3
SERVICE MENU SETTING ITEMS
Table 4
Setting item Setting value
POWER Off
SUB POWER On
VOLUME 15
COLOR SYSTEM NTSC
SOUND SYSTEM M
PICTURE MODE (VSM) BRIGHT
CINEMA SURROUND OFF
SUPER BASS ON [AV-21VT34/P]
OFF TIMER OFF
CLOSED CAPTION OFF
CHANNEL POSITION PR02
Setting item Setting value
INPUT TV
VNR AUTO
COMPRESS (16:9) OFF
AUTO SHUTOFF OFF
CHILD LOCK OFF
BLUE BACK ON
VIDEO-2 SET VIDEO
AUTO PROGRAM
Refer to OPERATING INSTRUCTIONS
CHANNEL SUMMARY Refer to OPERATING INSTRUCTIONS
WHITE BALANCE COOL
TINT Centre
COLOUR Centre
BRIGHT Centre
CONT Maximum
SHARP Centre
BALANCE Centre
SOUND MODE DYNAMIC
SOUND TURBO OFF
AI VOLUME ON
MTS STEREO
FAVORITE CH RED PR02
FAVORITE CH GREEN PR03
FAVORITE CH YELLOW PR04
FAVORITE CH BLUE PR05
AI ECO SENSOR OFF
AI ECO DISPLAY ON
Setting item Setting value
1. IF 1. VCO
2. DELAY POINT
2. V/C 1. SCREEN
2. CUTOFF(B/G)
3. WDR(R/G/B)
4. BRIGHT(TV/VDO 1/2/3)
5. CONT(TV/VDO 1/2/3/TV 16:9/VDO 16:9)
6. COLOUR(TV/VDO1/2/3/DVD)
7. TINT(TV/VDO 1/2/3)
8. SHARP [Do not adjust]
9. Y DELAY [Do not adjust]
10. TINT DVD [Do not adjust]
11. AMP T. SHARP
3. AUDIO
[Do not adjust]
1. DCXO ADJ
2. NICAM lower ERRLIM
3. NICAM upper ERRLIM
4. A2 ID THR
5. MENU EQUALIZER
4. DEF 1. V-SHIFT
2. V-SLOPE
3. V-SIZE
4. H-CENT
5. H-SIZE
6. TRAPEZ
7. EW-PIN
8. COR-UP
9. COR-LO
10. ANGLE
11. BOW
12. V-S.CR
13. V-LIN
14. V-ZOOM
15. V-SCROLL
5. VSM W/B
(BRIGHT/STANDARD/SOFT)
(COOL/WARM/NORMAL)
1. BRIGHT
2. CONT
3. COLOUR
4. SHARP
5. HUE
1. R DRIVE
2. G DRIVE
3. B DRIVE
6. STATUS
[Display only]
7. PLUG & PLAY(ON)
[Display only]

(No.YA140)1-13
3.3 REPLACEMENT OF CHIP COMPONENT
3.3.1 CAUTIONS
(1) Avoid heating for more than 3 seconds.
(2) Do not rub the electrodes and the resist parts of the pattern.
(3) When removing a chip part, melt the solder adequately.
(4) Do not reuse a chip part after removing it.
3.3.2 SOLDERING IRON
(1) Use a high insulation soldering iron with a thin pointed end of it.
(2) A 30w soldering iron is recommended for easily removing parts.
3.3.3 REPLACEMENT STEPS
1. How to remove Chip parts
[Resistors, capacitors, etc.]
(1) As shown in the figure, push the part with tweezers and
alternately melt the solder at each end.
(2) Shift with the tweezers and remove the chip part.
[Transistors, diodes, variable resistors, etc.]
(1) Apply extra solder to each lead.
(2) As shown in the figure, push the part with tweezers and
alternately melt the solder at each lead. Shift and remove
the chip part.
NOTE :
After removing the part, remove remaining solder from the
pattern.
2. How to install Chip parts
[Resistors, capacitors, etc.]
(1) Apply solder to the pattern as indicated in the figure.
(2) Grasp the chip part with tweezers and place it on the
solder. Then heat and melt the solder at both ends of the
chip part.
[Transistors, diodes, variable resistors, etc.]
(1) Apply solder to the pattern as indicated in the figure.
(2) Grasp the chip part with tweezers and place it on the
solder.
(3) First solder lead Aas indicated in the figure.
(4) Then solder leads Band C.
SOLDER SOLDER
A
B
C
A
B
C

1-14 (No.YA140)
SECTION 4
ADJUSTMENT
4.1 ADJUSTMENT PREPARATION
(1) You can make the necessary adjustments for this unit with either the remote control unit or with the adjustment
equipment and parts as given below.
(2) Adjustment with the remote control unit is made on the basis of the initial setting values, however, the new setting
values used for setting the screen to its optimum condition may differ from the initial settings.
(3) Make sure that AC power is turned on correctly.
(4) Turn on the power for the set and test equipment before use, and start the adjustment procedures after waiting at least 30
minutes.
(5) Unless otherwise specified, prepare the most suitable reception or input signal for adjustment.
(6) Never touch any adjustment parts, which are not specified in the list for this variable resistors, transformers, trimmer capacitors,
etc.
4.2 PRESETTING BEFORE ADJUSTMENT
Unless otherwise specified in the adjustment instructions, preset the following functions with the remote control unit.
User mode setting position
4.3 MEASURING INSTRUMENT AND FIXTURES
(1) DC voltmeter (or Digital voltmeter)
(2) Oscilloscope
(3) Signal generator (Pattern generator) [PAL/SECAM/NTSC]
(4) Remote control unit
4.4 ADJUSTMENT ITEMS
B1 VOLTAGE
FOCUS ADJUSTMENT
IF CIRCUIT ADJUSTMENTS
• IF VCO adjustment
• DELAY POINT (AGC TAKE-OVER) adjustment
VIDEO CIRCUIT ADJUSTMENTS
• WHITE BALANCE (Low light) adjustment
• WHITE BALANCE (High light) adjustment
• SUB BRIGHT adjustment
• SUB CONTRAST adjustment
• SUB COLOUR 1 adjustment
• SUB COLOUR 2 adjustment
• SUB TINT 1 adjustment
• SUB TINT 2 adjustment
AUDIO SETTING
DEFLECTION CIRCUIT ADJUSTMENTS
• V.SLOPE adjustment
• V.POSITION adjustment
• V.HEIGHT adjustment
• H.POSITION adjustment
• V.S-CURVE adjustment
• H. PARALLEL adjustment
• H.BOW adjustment
VSM PRESET SETTING
PURITY AND CONVERGENCE ADJUSTMENTS
• PURITY adjustment
• STATIC CONVERGENCE adjustment
• DYNAMIC CONVERGENCE adjustment
Setting item Setting value
PICTURE MODE (VSM) BRIGHT
TINT, COLOUR, BRIGHT,SHARP Centre
CONT Maximum
VNR OFF
AI ECO SENSOR OFF
BALANCE Centre
SOUND TURBO OFF
CINEMA SURROUND OFF
COMPRESS 4:3

(No.YA140)1-15
4.5 ADJUSTMENT LOCATIONS
TOP
CRT EARTH
DEG COIL
(SOLDER SIDE)
(BRAIDED ASS'Y)
U
TP-47R/G
HV
41
GND
CN00X
1. B1
2. NC
3. X-RAY2
4. X-RAY1
5. GND
B1
UPPER : FOCUS
DEF
YOKE
IC702
MAIN PWB ASS'Y (CRT SOCKET)
T
6
1
41
FRONT
HVT
MAIN PWB ASS'Y
1
6
1
41
14
5
61
X
U
LOWER : SCREEN
TU001
J809
S901
J808
S805 S803 S801
S804 S802 J807 J806
J804J801 J802 J803
IC701
CN00S
CN00C
T
PW
DEG
POWER
CORD
TP-E
E1
TP-47B
POWER SW
TP-47R
CN00C
1. 5V
2. SCLO
3. SDAO
4. SCL1
5. SDA1
6. GND
I
2
C

1-16 (No.YA140)
4.6 BASIC OPERATION IN SERVICE MENU
Operate the SERVICE MENU with the remote control unit.
4.6.1 SERVICE MENU ITEMS
With the SERVICE MENU, various settings (adjustments) can be made, and they are broadly classified in the following items of settings:
4.6.2 BASIC OPERATION IN SERVICE MENU
1. HOW TO ENTER SERVICE MENU
Press the [DISPLAY] key and the [PICTURE MODE] key on the remote control unit simultaneously.
The SERVICE MENU screen will be displayed. (See Fig. 1 on the next page.)
2. SELECTION OF SUB MENU SCREEN
Press one of the keys 1 to 6 on the remote control unit, and select the SUB MENU SCREEN from the SERVICE MENU. (See Fig. 1 on the next page.)
SERVICE MENU →SUB MENU
3. METHOD OF SETTING
NOTES:
• Once the setting values are set, they are memorized automatically.
• It must not be adjusted without inputting a signal.
(1) 1. IF
[1.VCO ] : Under normal conditions, no adjustment is required.
[2.DELAY POINT ]
(2) 2. V/C, 3. AUDIO and 4. DEF
(3) 5. VSM W/B
(4) 6. STATUS
This is for display only.
(5) 7. PLUG & PLAY (ON)
This is not used for service.
4. Release of SERVICE MENU
After completing the setting, return to the SERVICE MENU by pressing the [DISPLAY] key, then again press the [DISPLAY] key to
return to the normal screen.
1. IF For entering/adjusting the setting values (adjustment values) of the IF circuit.
2. V/C For entering/adjusting the setting values (adjustment values) of the VIDEO circuit.
3. AUDIO For entering/adjusting the setting values (adjustment values) of the AUDIO circuit.
4. DEF For entering/adjusting the setting values (adjustment values) of the DEFLECTION circuit.
5. VSM W/B For setting the values of STANDARD, SOFT, BRIGHT and COOL, NORMAL, WARM.
6. STATUS This is not used for service.
7. PLUG & PLAY (ON) This is not used for service.
1. IF 5. VSM W/B
2. V/C 6. STATUS
3. AUDIO 7. PLUG & PLAY (ON)
4. DEF
(a) [1] key Select 1. IF.
(b) [1] key Select 1. VCO.
(c) [DISPLAY] key When this is pressed twice, you will return to the SERVICE MENU.
(a) [1] key Select 1. IF.
(b) [2] key Select 2. DELAY POINT.
(c) MENU [] / [] key Adjust the setting value.
(d) [DISPLAY] key When this is pressed twice, you will return to the SERVICE MENU.
(a) [2] ~[4] keys Select one from 2. V/C, 3. AUDIO and 4. DEF
(b) MENU [] / [] key Select setting items.
(c) MENU [] / [] key Adjust the setting values of the setting items.
Use the number keys on the remote control unit for setting the WHITE BALANCE.
For the setting, refer to each item concerned.
(d) [DISPLAY] key When this is pressed, you will return to the SERVICE MENU.
(a) [5] keys Select 5. VSM W/B.
(b) MENU [OK] key Select preset items.
(c) MENU [] / [] key Adjust setting items.
(d) MENU [] / [] key Adjust the setting values of the setting items.
(e) [DISPLAY] key When this is pressed, you will return to the SERVICE MENU.

(No.YA140)1-17
4.6.3 SERVICE MENU FLOW CHART
Fig.1
1. IF
SERVICE MENU
1. VCO
2. DELAY POINT
IF SERVICE MENU VCO (CW) *****MHz
TOO HIGH
ABOVE REFERENCE
JUST REFERENCE
BELOW REFERENCE
TOO LOW
DELAY POINT
AGC TAKEOVER **
2. V/C
Setting item
1. SCREEN
2. CUTOFF (B/G)
3. WDR (R/G/B)
4. BRIGHT (TV/VDO1/2/3)
5. CONT (TV/VDO1/2/3/TV
16:9/VDO16:9)
6. COLOUR (TV/VDO1/2/3/
DVD)
7. TINT (TV/VDO1/2/3)
1. DCXO ADJ
2. NICAM lower ERRLIM
3. NICAM upper ERRLIM
4. A2 ID THR
Setting item
8. SHARP (TV/VDO1/2/3)
9.
Y DELAY (TV/VDO1/2/3
/S-DVO)
10. TINT DVD
11. AMP T.SHARP
3. AUDIO
PAL
1. SCREEN HBC
WBC
BRI
**
**
**
V/C
000A
0002
0009
5. VSM W/B
1. BRIGHT ***
VSM PRESET BRIGHT
4. DEF
1. V-SHIFT ***
(**)
DEF FULL 50Hz
1. BRIGHT
2. CONT
3. COLOUR
4. SHARP
5.HUE
1. R-DRIVE
2. G-DRIVE
3. B-DRIVE
Setting item
4 : 3 / 16 : 9
1. V-SHIFT
2. V-SLOPE
3. V-SIZE
4. H-CENT
5. H-SIZE
6. TRAPEZ
7. EW-PIN
8. COR-UP
9. COR-LO
10. ANGLE
11. BOW
12. V-S. CR
13. V-LIN
14. V-ZOOM
15. V-SCROLL
Setting item
1. IF
3. AUDIO
5. VSM W/B
7. PLUG & PLAY (ON)
2. V/C
4. DEF
6. STATUS
SERVICE MENU
1-7 : SELECT DISPLAY : EXIT
******* **** ***** *****
**** **** *** ***
6. STATUS
ECO EOF NOL VNR
COSMIC STATUS
STATUS 1. DCXO ADJ. = ***
NOT NICAM
AUDIO
*******
*******
*******
***********
** ** ** ** ** ** ** **
V/C STATUS
MENU EQUALIZER
DYNAMIC
MUSIC
NEWS
USER
Setting value (Hexadecimal)
Setting value
Sereen size
FULL
COMPRESS

1-18 (No.YA140)
4.7 ADJUSTMENT PROCEDURE
4.7.1 B1 VOLTAGE
4.7.2 FOCUS ADJUSTMENT
4.7.3 IF CIRCUIT ADJUSTMENTS
Item Measuring
instrument Test point Adjustment part Description
B1 VOLTAGE
check
Signal
generator
DC voltmeter
B1 (pin 1)
GND (pin 5)
[CN00X
connector in
MAIN PWB]
(1) Receive a black and white signal.
(2) Connect a DC voltmeter between B1 and GND
(between pins 1 and 5 of the connector CN00X).
(3) Make sure that the voltage is DC134.5V ±2V.
Item Measuring
instrument Test point Adjustment part Description
FOCUS
adjustment
Signal
generator
FOCUS VR
[In HVT]
Notes:
• Set PICTURE MODE (VSM) to "BRIGHT".
• The final adjustment of CONVERGENCE must be
done after the FOCUS adjustment. (CONVERGENCE
is affected by the FOCUS adjustment.)
If any aeviation in CONVERGENCE is found, PURITY
must be adjusted to restore the convergence.
(1) Receive a crosshatch signal.
(2) Adjust the FOCUS VR so that the vertical and
horizontal lines will be clear and in fine detail on the
screen.
(3) Make sure that the picture is in focus even when the
screen gets darkened.
Item Measuring
instrument Test point Adjustment part Description
IF VCO
check
Remote
control unit
[1. IF]
1. VCO (CW)
Note:
• Under normal conditions, no adjustment is required.
(1) Receive a broadcast signal.
(2) Select 1. IF from the SERVICE MENU.
(3) Select 1. VCO.
(4) Check the characters colour of the JUST
REFERENCE displayed to yellow.
(5) Press the [DISPLAY] key three times to return to
normal screen.
DELAY POINT
(AGC
TAKE-OVER)
adjustment
Remote
control unit
[1. IF]
2. DELAY POINT
(1) Receive a black and white broadcast signal (colour off).
(2) Select 1. IF from the SERVICE MENU.
(3) Select 2. DELAY POINT.
(4) Adjust in order to eliminate any noise or beat from
the image. Any increase above the initial value
produces the noise and any decrease below it
produces the beat.
(5) Press the [DISPLAY] key three times to return to the
normal screen.
(6) Turn to other channels and make sure that there are
no irregularities.
TOO HIGH
ABOVE REFERENCE
BELOW REFERENCE
JUST REFERENCE
TOO LOW
VCO (CW) . MHz
DISPLAY : EXIT
Receiving frequency
YELLOW
Initial setting value
Adjustment item
NTSC 3.58
VHF UHF
2. DELAY POINT
(AGC TAKE-OVER) 35
35

(No.YA140)1-19
4.7.4 VIDEO CIRCUIT ADJUSTMENTS
• The setting (adjustment) using the remote control unit is made on the basis of the initial setting values.
• The setting values which adjust the screen to the optimum condition can be different from the initial setting values.
• Do not change the initial setting values of the setting (adjustment) items not listed in "ADJUSTMENT PROCEDURE".
• The initial setting values in parenthesis ( ) are fixed offset values, needing no further adjustment.
Adjustment item Variable range
Initial setting value
PAL SECAM
NTSC3.58 NTSC4.43
COMPONENT (V-2)
525i 625i
1. SCREEN BRI 0 ~ 63 32 32 32 32 32 32
2. CUTOFF B 0 ~ 63 (-32 ~ [phone] (+3) (+3)
G 0 ~ 63 (-32 ~ +31) 7 7 7 7 (-5) (-5)
3. WDR R 0 ~ 63 (-32 ~ [phone] (0) (0)
G 0 ~ 63 (-32 ~ [phone] (0) (0)
B 0 ~ 63 (-32 ~ [phone] (0) (0)
4. BRIGHT RF 0 ~ 63 (-32 ~ +31) --- --- 39 --- --- ---
VIDEO 1(COMPOSITE/S) (-32 ~ +31) (+1) (+1) (+1) (+1) --- ---
VIDEO 2(COMPONENT) (-32 ~ +31) (+1) (+1) (+1) (+1) (+2) (+2)
VIDEO 3(COMPOSITE) (-32 ~ +31) (+1) (+1) (+1) (+1) --- ---
5. CONT. RF 0 ~ 63 --- --- 32 --- --- ---
VIDEO (-32 ~ +31) (-3) (-3) (-3) (-3) (-2) (-2)
RF 16:9 (-32 ~ +31) (-2) (-2) (-2) (-2) --- ---
VIDEO 16:9 (-32 ~ +31) --- --- --- --- --- ---
6. COLOUR RF 0 ~ 63 (-32 ~ +31) --- --- 37 --- --- ---
VIDEO 0 ~ 63 (-32 ~ +31) 42 30 (+3) (+3) (+9) (+0)
7. TINT RF 0 ~ 63 (-32 ~ +31) --- --- 32 --- --- ---
VIDEO (-32 ~ +31) --- --- (+2) (+2) --- ---
8. SHARP RF 0 ~ 63 --- --- 54 --- --- ---
VIDEO 0 ~ 63 54 54 54 54 40 40
9. Y DELAY RF 0 ~ 15 --- --- 3 --- --- ---
VIDEO 0~15 2433------
S-VIDEO 0 ~ 15 7 10 7 7 --- ---
10. TINT DVD VIDEO, S-VIDEO 0 ~ 63 34 31 32 32 --- ---
COMPONENT (-32 ~ +31) --- --- --- --- (+1) (0)
11. AMP T.SHARP RF, VIDEO 0 ~ 63 0 0 0 0 0 0
Item Measuring
instrument Test point Adjustment part Description
WHITE
BALANCE
(Low light)
adjustment
Signal
generator
Remote
control unit
[2. V/C]
2. CUTOFF (B)
2. CUTOFF (G)
SCREEN VR
[In HVT]
Note:
• Set PICTURE MODE (VSM) to "BRIGHT".
- COMPOSITE WHITE BALANCE -
(1) Receive a PAL black and white signal (colour off).
(2) Select 2. V/C from the SERVICE MENU.
(3) Select 2. CUTOFF (B) and (G).
(4) Set each value to initial setting value with the [4] /
[7] keys and [5] / [8] keys.
(5) Turn the SCREEN VR fully counterclockwise, then
slowly turn it clockwise to where a red, blue or
green colour is faintly visible.
(6) Use the [4] / [7] and [5] / [8] keys to adjust so that
the other 2 colours appear white.
(7) Turn the SCREEN VR to where the single
horizontal line glows faintly.
(8) Press the [DISPLAY] key twice to return to the
normal screen.
- COMPONENT WHITE BALANCE -
(1) Receive a PAL component black and white signal
(colour off).
(2) Select VIDEO-2 SET from the MENU and set
VIDEO-2 SET to COMPONENT.
(3) Adjust COMPONENT WHITE BALANCE in the
same way as ”COMPOSITE WHITE BALANCE”.
Adjustment Item Variable Initial setting value
range
2. CUT OFF B 0 ~ 63(-32~+31)
0 ~ 63(-32~+31)
(+3)
G (-5)
11
7
COMPOSITE COMPONENT
PAL
2. CUTOFF (B)
(G) **
**
(**)
(**)
V/C
G CUTOFF (

)
12 3
4
789
56
B CUTOFF (

)
B CUTOFF (

)
G CUTOFF (

)
REMOTE CONTROL UNIT

1-20 (No.YA140)
WHITE
BALANCE
(High light)
adjustment
Signal
generator
Remote
control unit
[2. V/C]
3. WDR (R)
3. WDR (G)
3. WDR (B)
Notes:
• Proceed to the following adjustment after having
completed the WHITE BALANCE (Low light) adjustment.
• Set PICTURE MODE (VSM) to "BRIGHT".
(1) Receive a PAL black and white signal (colour off).
(2) Select 2. V/C from the SERVICE MENU.
(3) Select 3. WDR (R), (G) and (B).
(4) Set each value to initial setting value with the [4] to
[9] keys.
(5) Use the [4] to [9] keys to produce a white screen.
(6) Press the [DISPLAY] key twice to return to the normal
screen.
SUB BRIGHT
adjustment
Remote
control unit
[2. V/C]
4. BRIGHT
Notes:
• Proceed to the following adjustment after having
completed the WHITE BALANCE (Low light) and
WHITE BALANCE (High light) adjustment.
• Set PICTURE MODE (VSM) to "BRIGHT".
(1) Receive a broadcast.
(2) Select 2. V/C from the SERVICE MENU.
(3) Select 4. BRIGHT.
(4) Set the initial setting value.
(5) If the brightness is not best with the initial setting value,
make fine adjustment until you get the best brightness.
(6) Press the [DISPLAY] key twice to return to the
normal screen.
SUB
CONTRAST
adjustment
Remote
control unit
[2. V/C]
5. CONT
Notes:
• Proceed to the following adjustment after having
completed the SUB BRIGHT adjustment.
• Set PICTURE MODE (VSM) to "BRIGHT".
(1) Receive a broadcast.
(2) Select 2. V/C from the SERVICE MENU.
(3) Select 5. CONT.
(4) Set the initial setting value.
(5) If the contrast is not best with the initial setting value,
make fine adjustment until you get the best contrast.
(6) Press the [DISPLAY] key twice to return to the
normal screen.
Item Measuring
instrument Test point Adjustment part Description
0 ~ 63
0 ~ 63
0 ~ 63
Adjustment Item Variable Initial setting
range value
R32
3. WDR G 32
B45
G DRIVE (

)
12 3
4
789
56
R DRIVE (

)B DRIVE (

)
B DRIVE (

)
R DRIVE (

)
G DRIVE (

)
REMOTE CONTROL UNIT
PAL
3. WDR (R)
(G) **
**
(**)
(**)
(B) ** (**)
V/C