JVC AV-29MXP6/V User manual

SERVICE MANUAL
COPYRIGHT © 2006 Victor Company of Japan, Limited No.YA476
2006/10
FLAT COLOUR TELEVISION
YA476200610
AV-21MXP6/V,
AV-25MXP6/V,
AV-29MXP6/V
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-42
[AV-21MXP6/V] [AV-25MXP6/V]
[AV-29MXP6/V]
BASIC CHASSIS
CW3

1-2 (No.YA476)
SPECIFICATION
Design and specifications subject to change without notice.
Items Contents
AV-21MXP6/V AV-25MXP6/V AV-29MXP6/V
Dimensions (W ×H ×D) 64.9 cm ×46.5 cm ×46.9 cm 72.8 cm ×53.6 cm ×47.6 cm 81.2 cm ×58.4 cm ×52.1 cm
Mass 23.5 kg 32.0 kg 43.0 kg
TV RF System B, G, I, D, K, M
Colour System PAL / SECAM / NTSC 3.58 / NTSC 4.43
Stereo System PB STREO
Teletext System - - -
Receiving
Frequency
VHF Low 46.25MHz - 140.25MHz (AS0 - S6)
VHF High 147.25MHz - 423.25MHz (S7 - S36)
UHF 431.25MHz - 863.25MHz (S37 - C57)
CATV Mid (X - Z+2, S1 - S10) / Super (S11 - S20) / Hyper (S21 - S41) bands
Intermediate
Frequency
VIF 38.0MHz (B, G, I, D, K, M)
SIF 32.26 MHz (5.74 MHz: B), 32.15MHz (5.85 MHz: G), 31.45 MHz (6.55 MHz: I)
31.75 MHz (6.5 MHz: D), 32.15MHz (5.85 MHz: K), 33.5MHz (4.5MHz : M)
Colour Sub
Carrier
PAL 4.43 MHz
SECAM 4.40625 MHz / 4.25 MHz
NTSC 3.58 MHz / 4.43 MHz
Power Input AC110 V - AC240 V, 50 Hz/60 Hz (Operating Voltage 90V~260V)
Power Consumption 105W (Max)/ 73W (Avg) 137W (Max)/ 91w (Avg) 170W (Max)/ 109w (Avg)
Picture Tube Visible size : 52.1 cm,
Measured diagonally
H: 41.6 cm ×V: 31.5 cm
Visible size : 61.0 cm,
Measured diagonally
H: 48.6 cm ×V: 36.8 cm
Visible size : 69.0 cm,
Measured diagonally
H: 55.1 cm ×V: 41.6 cm
High Voltage 28.5 kV ±1.5 kV
(at zero beam current)
30.5 kV ±1.5 kV
(at zero beam current)
31.5 kV +1kV/-1.5kV
(at zero beam current)
Speaker 6.5 cm ×13 cm, oval type ×2
Audio Power Output 7 W + 7 W (Rated power output)
10 W + 10 W (Rated power output)
Aerial Input 75 Ωunbalanced, coaxial
Video / Audio
Input-1/2/3
Component Video
[VIDEO-2]
RCA pin jack ×3
Y:1V(p-p), positive (negative sync), 75Ω
Cb/Cr:0.7V(p-p), 75Ω
S-Video
[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 1V(p-p), negative sync, 75Ω, RCA pin jack ×3
Audio 500mV(rms) (-4dBs), high impedance, RCA pin jack ×6
Video / Audio
Output
Video 1V(p-p), 75?, RCA pin jack ×1
Audio 500mV(rms)(-4dBs), Low impedance, RCA pin jack ×2
Headphone jack 3.5 mm stereo mini jack ×1
Remote Control Unit RM-C1285 (UM-3/AA/R6 dry cell battery ×2)

(No.YA476)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 VOLTAGE).
(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.YA476)
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
2.1 FEATURES
DVD PICTURE MODE
This function can enhance the picture quality of DVD. The
screen can be made sharp or soft by this setting.
AUTO SIGNAL DETECT
When input DVD signal to VIDEO-2, detect the input signal
and change the input mode to VIDEO-2 automatically.
CINEMA SURROUND
This function can enjoy an enhanced sound for wider
audience.
PICTURE MODE
This function can adjust the picture settings automatically.
There are BRIGHT, STANDARD and SOFT in the PICTURE
MODE.
RETURN +
This function can set a channel frequently view to the Return
Channel and you can view that channel at any time with one-
touch.
AI ECO SENSOR
This function can adjust TV screen contrast according to the
brightness of your room.
MaxxBass
MaxxBass enhances bass sound that cannot be reproduced
by normal speakers to be heard by our ears.
2.2 MAIN DIFFERENCE LIST
Item AV-21MXP6/V AV-25MXP6/V AV-29MXP6/V
MAIN PWB SCW-1645A-H2 SCW-1646-H2 SCW-1647A-H2

(No.YA476)1-5
2.3 TECHNINAL INFORMATION
2.3.1 MAIN MI-COM (CPU) PIN FUNCTION
Pin
No. Pin name I/O Function Pin No. Pin name I/O Function
1 VssP2 - GND 65 SVM O Not used
2 VssC4 - GND 66 FbiSo I Flyback input/sandcastle output
3 V1.8C4 I 1.8V (Digital) 67 Hout O Horizontal output
4 V3.3A3 I 3.3V 68 VssComb - GND
5 VrefP_Sdac I 3.3V (Positive) 69 V5Comb I 5V
6 VrefN_Sdac - GND 70 Vin/R2/Pr I PIP R input
7 VrefP_Sdac I 3.3V (Negative) 71 Uin/B2/Pb I PIP B input
8 VrefN_Sdac - GND 72 Yin/G2/Y I PIP G input
9 VrefP_Sdac I 3.3V (Positive) 73 Ysync I Not used
10 XtalIn I 24.576MHz for system clock 74 Yout O Not used
11 XtalOut O 24.576MHz for system clock 75 Uout/INSSW2 I YUV insertion input
12 VssA1 - GND 76 NC O Not used
13 NECK I V-guard input/ I/O switch 77 INSSW3 I YUV insertion input
14 CONT I 1.8V regulator control 78 R3/Pr I Component PR input (Video-2)
15 V5P1 I +5V 79 G3/Y I Component Y input (Video-2)
16 Ph2 - Phase-2 filter 80 B3/Pb I Component PB input (Video-2)
17 Ph1 - Phase-1 filter 81 Gnd3 - GND
18 Gnd1 - GND 82 V5P3 I 5V
19 SecPll - SECAM PLL decoupling 83 BCL I Beam current limiter input
20 Dec8G - Bandgap decoupling 84 BLKIN I Black current input
21 EW O East-West drive output 85 Rout O R output
22 VDRB- O Vertical drive B output 86 Gout O G output
23 VDRA+ O Vertical drive A output 87 Bout O B output
24 Vif1 I Video IF input 1 88 V3.3A1 I 3.3V
25 Vif2 I Video IF input 2 89 RefAdN - GND
26 Vsc - Vertical sawtooth capacitor 90 V3.3RefAdP I 3.3V (Positive)
27 Iref I Reference current input 91 RefAd I 3.3/2V
28 GndIF - GND 92 GndA - GND
29 Sif1 I Sound IF input 1 93 V1.8A I 1.8V
30 Sif2 I Sound IF input 2 94 V3.3A2 I 3.3V
31 AGC O Tuner AGC output 95 VssADC - GND
32 EHT I EHT/overvoltage protection input 96 V1.8ADC I 1.8V
33 Ssif/RefIn/Avl/
RefOut
O Automatic Volume Levelling/ sound IF input / subcar-
rier reference output / external reference signal input
for I signalmixer for DVB operation
97 REMOTE I Remote control
34 L3 I Audio-L3 input (left signal) 98 PW_LED I POWER LED control
35 R3 I Audio-R3 input (right signal) 99 PW_LED I POWER LED control
36 L-OUT O Audio L output 100 V1.8C2 I 1.8V
37 R-OUT O Audio R output 101 VssC2 - GND
38 DecsDem - Decoupling sound demodulator 102 TIMER - Not used
39 QssO/AmO/
AudeEm
O QSS intercarrier output / AM output / deemphasis /
(front-end audio out)
103 TIMER - Not used
40 Gnd2 - GND 104 VER_PROTECT O X-ray protect
41 PllIf - IF-PLL loop filter 105 S_REDUCE O Sound control
42 SifAgc - AGC sound IF 106 P00/I2SDI1 O Not used
43 IfVo/FmRo/DvbO O Not used 107 POWER O SUB POWER control
44 NC O Not used 108 SCL1 I I2C bus clock
45 V8AudioSwitches I 8V 109 SDA1 I/O I2C bus data
46 AgcSsif - AGC capacitor second sound IF 110 V3.3P I 3.3V
47 V5P2 I 5V 111 ROTATION O Rotation
48 V-OUT O Video output 112 3.58/OTHER O NTSC 3.58 detection
49 L1 I Audio-L1 input 113 A_MUTE O Audio muting
50 R1 I Audio-R1 input 114 4.5/OTHER O NTSC 4.43 detection
51 V3 I Video V3 input 115 PROT I Protect
52 C4 I Not used 116 ECO_IN I ECO sensor level detection
53 Audio2InL I Not used 117 V1.8C1 I 1.8V (Digital)
54 Audio2InR I Not used 118 DecV1V8 I 1.8V
55 V2/Y I Video V2 input 119 KEY_IN I Key scan data
56 L2 I Audio L2 input (Left signal) 120 VDO-DET I Video DET input
57 R2 I Audio R2 input (right signal) 121 VSSC1+P1 - Digital GND
58 Y3/Cvbs I S-Video Y1 input 122 S_V_DET I S-Video DET input
59 C1 I S-Video C1 input 123 P25/PWM4 O GTVA_reset
60 AudioLsL O Audio L output for audio power amplifier 124 V1.8C3 I 1.8V (Digital)
61 AudioLsR O Audio R output for audio power amplifier 125 VssC3 - GND
62 HP-L O Not used 126 P12/Int2 I External interrupt
63 HP-R O Not used 127 SDA0 I/O I2C bus data (for memory)
64 CVBSO/PIP O CVBS / PIP output 128 SCL0 I I2C bus clock (for memory)