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No.51844
Sep. 2001
AV-20N11
AV-20N31
1
COPYRIGHT © 2001 VICTOR COMPANY OF JAPAN, LTD.
Sept. 2001
AV-20N11/PH
AV-20N31/PH
CONTENTS
! SPECIFICATIONS
2
! SAFETY PRECAUTIONS
3
! FEATURES
4
! MAIN DIFFERENCE LIST
4
! SPECIFIC SERVICE INSTRUCTIONS
4
! SERVICE ADJUSTMENTS
10
! PARTS LIST
29
STANDARD CIRCUIT DIAGRAM (APPENDIX)
2-1
OPERATING INSTRUCTIONS
SERVICE MANUAL
COLOR TELEVISION
BASIC CHASSIS
GA2
!!


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No.51844
AV-20N11
AV-20N31
2
SPECIFICATIONS
Contents
Items
AV-20N11
AV-20N31
Dimensions (W×
×
×
×H×
×
×
×D)
619mm×458mm×488mm
Mass
19.0kg
TV RF System
CCIR (M)&(N)
Color / Sound System
NTSC / PAL-M / PAL-N
NTSC / PAL-M / PAL-N
BTSC (Multi Channel Sound)
TV Receiving Channels
and Frequency
VL Band
VH Band
UHF Band
(0206) 54MHz88MHz
(0713) 174MHz216MHz
(1469) 470MHz806MHz
CATV
Receiving
Channels
and Frequency
Low Band
High Band
Mid Band
Super Band
Hyper Band
Ultra Band
Sub Mid Band
(0206)
(0713)
(1422)
(2336)
(3764)
(6594, 100125)
(01, 9699)
TV/CATV Total Channel
180 Channels
Intermediate Frequency
Video IF Carrier
Sound IF Carrier
45.75MHz
41.25MHz (4.5MHz)
Color Sub Carrier
NTSC
: 3.579545MHz
PAL-M
: 3.57561149MHz
PAL-N
: 3.58205625MHz
Antenna terminal
75(VHF/UHF) Terminal, F-Type Connector
Power Input
Rated Voltage : 110V240V AC, 50Hz/60Hz
Operating Voltage : 90V260V AC, 50Hz/60Hz
Power Consumption
60W
Picture Tube (measured diagonally)
Picture tube 52cm / Visible area 48cm
High Voltage
25.5kV±1.0kV (at zero beam current)
Speaker
5cm×12cm Oval type×2
Audio Power Output
2W (monaural)
1.5W+1.5W (stereo)
Input
Video input
Audio input
1Vp-p 75 (RCA pin jack)
500mVrms (-4dBs) / High impedance
(RCA pin jack)
Output
Video output
Audio output
1Vp-p 75 (RCA pin jack)
500mVrms (-4dBs) / Low impedance
(RCA pin jack)
Headphone Jack
Stereo mini Jack (dia. 3.5mm, Sound is monaural)
Stereo mini jack (dia. 3.5mm, Sound is stereo)
Remote Control Unit
RM-C372GY
(AA/R6/UM-3 battery×2)
RM-C373GY
(AA/R6/UM-3 battery×2)
Design & specifications are subject to change without notice.
(54MHz804MHz)


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No.51844
AV-20N11
AV-20N31
3
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 with a measuring apparatus (oscilloscope etc.)
the LIVE side GND and ISOLATED(NEUTRAL) side GND or
EARTH side GND at the same time.
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
ADJUSTMENT OF B1 POWER SUPPLY).
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 10k
" 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, screwheads, earphone jack, control shafts, etc.)
to be sure the product is safe to operate without danger of
electrical shock.
(1) 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.
(2) 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 1000 ohms per volt or more sensitivity in the following
manner. Connect a 1500
" 10W resistor paralleled by a 0.15#F
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.).
0.15F AC-TYPE
1500 " 10W
GOOD EARTH GROUND
PLACE THIS PROBE
ON EACH EXPOSED
METAL PART
AC VOLTMETER
(HAVING 1000 "/V,
OR MORE SENSITIVITY)


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No.51844
AV-20N11
AV-20N31
4
FEATURES
" New chassis design enables use of a main board with simplified
circuitry.
" Provided with miniature tuner (TV/CATV).
" PLL synthesizer system TV/CATV totaling 180 channels.
" Multifunctional remote control permits picture adjustment.
" With NTSC/PAL-M & PAL-N color/sound system.
" Adoption of the VIDEO STATUS function.
" With 75V/U in common (F-Type) ANT Terminal.
" Wide range voltage (90V260V) AC power input.
" Closed-caption broadcasts can be viewed. (AV-20N31)
MAIN DIFFERENCE LIST
!
Symbol
No.
Model
Part name
AV-20N11
AV-20N31
Remarks
MAIN PWB ASS'Y
SGA-1057A-H2
SGA-1054A-H2
!
FRONT CABINET
LC10438-020A-HK
LC10438-021A-HK
TERMINAL SHEET
LC30819-002A
LC30819-001A
SP01/02
SPEAKER
CEBSS12D-07KJ2
CEBSS12D-04KJ2
( x2 )
!
RATING LABEL
GG20003-016A-H
GG20003-017A-H
PACKING CASE
GG10057-009A-P
GG10057-010A-P
REMOCON UNIT
RM-C372GY-1H
RM-C373GY-1H
POS LABEL
CP30902-064(R)
CP30902-065(R)
SPECIFIC SERVICE INSTRUCTIONS
DISASSEMBLY PROCEDURE
REMOVING THE REAR COVER
1. Unplug the power supply cord.
2. Remove the 6 screws marked !"
!"
!"
!"and 2 screws marked #"
#"
#"
#"as
shown in Fig.1.
3. Withdraw the REAR COVER toward you.
" When reinstalling the rear cover, carefully push it inward after
inserting the MAIN PWB into the rear cover groove.
REMOVING THE MAIN PW BOARD
" After removing the rear cover.
1. Slightly raise the both sides of the MAIN PW Board by hand and
withdraw the MAIN PW Board backward.
(If necessary, take off the wire clamp, connector etc.)
REMOVING THE SPEAKER
" After removing the rear cover.
1. Remove the 2 screws marked $
$
$
$as shown in Fig.1.
2. Follow the same steps when removing the other hand speaker.
CHECKING THE MAIN PW BOARD
1. To check the backside of the MAIN PW Board.
1) Pull out the MAIN PWB. (Refer to REMOVING THE MAIN
PWB).
2) Erect the chassis vertically so that you can easily check the
backside of the MAIN PW Board.
[CAUTION]
" When erecting the MAIN PWB, be careful so that there will be no
contacting with other PW Board.
" Before turning on power, make sure that the CRT earth wire and
other connectors are properly connected.
WIRE CLAMPING AND CABLE TYING
1. Be sure 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.


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No.51844
AV-20N11
AV-20N31
5
CRT SOCKET PWB
(Within MAIN PWB)
FRONT CABINET
(×2)
(×6)
SPEAKER
A
B
C
C
(×2)
(×2)
REAR COVER
MAIN PWB
Fig. 1
This exploded view describes
about AV-20N31.
Although AV-20N11 are slightly
different from this figure, you
can use the exploded view for
disassembling the AV-20N11 in
the same step as for the AV-
20N31.
SPEAKER