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No.51750
Jul. 2000
AV-25PS
1
COPYRIGHT © 2000 VICTOR COMPANY OF JAPAN, LTD.
AV-25PS
CONTENTS
! SPECIFICATIONS
2
! SAFETY PRECAUTIONS
3
! FEATURES
4
! FUNCTIONS
5
! SPECIFIC SERVICE INSTRUCTIONS
6
! SERVICE ADJUSTMENTS
12
STANDARD CIRCUIT DIAGRAM (APPENDIX)
2-1
! PARTS LIST
33
SERVICE MANUAL
COLOUR TELEVISION
BASIC CHASSIS
JK


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No.51750
AV-25PS
2
SPECIFICATIONS
Item
CONTENTS
Dimensions ( W×
×
×
×H×
×
×
×D )
655mm×530.5mm×465mm
Mass
36.0kg
TV RF System
B, G, I, D, K, K1, M
Colour System
PAL, SECAM, NTSC3.58, NTSC4.43
Stereo System
A2 / NICAM (B/G, I, D/K) system
Teletext System
FLOF (Fastext), WST (World standard system)
Receiving Frequency
VHF(L)
46.25MHz168.25MHz
VHF (H)
175.25MHz463.25MHz
UHF
471.25MHz 863.25MHz
CATV
Mid(X-Z, S1-S10), Super(S11-S20), Hyper(S21-S41) bands receivable
Intermediate Frequency
VIF Carrier
38.0MHz
SIF Carrier
33.5MHz(4.5MHz), 32.5MHz(5.5MHz), 32.0MHz(6.0MHz), 31.5MHz(6.5MHz)
Colour Sub Carrier Frequency
PAL
4.43MHz
SECAM
4.40625MHz, 4.25MHz
NTSC
3.58MHz / 4.43MHz
Power Input
AC 110V240V , 50/60Hz
Power Consumption
181W(Max) / 119W(Avg)
Picture Tube
Visible size : 60cm measured diagonally
High Voltage
31.0kV±1.5kV (at zero beam current)
Speaker & Audio Output
Open dome speaker
10W+10W, 10cm round×2
Video Audio Input terminals
S-Video
Y : 1V(p-p) positive (Negative sync provided, when terminated with 75)
C : 0.286V(p-p) (Burst signal, when terminated with 75)
Video
1V(p-p) 75(RCA pin jack)
Video1
Audio(L/R)
500mV(rms) (-4dBs), High impedance (RCA pin jack)
Video
1V(p-p) 75(RCA pin jack)
Video2
Audio(L/R)
500mV(rms) (-4dBs), High Impedance (RCA pin jack)
Video/Y
V : Composite video 1V(p-p) 75(RCA pin jack)
Y : Component video 1V(p-p) 75(RCA pin jack)
Cb
Component video B-Y 0.7V(p-p) 75(RCA pin jack)
Cr
Component video R-Y 0.7V(p-p) 75(RCA pin jack)
Video3
Audio(L/R)
500mV(rms) (-4dBs), High Impedance (RCA pin jack)
Video
1V(p-p) 75(RCA pin jack)
Video4
(Front terminal)
Audio(L/R)
500mV(rms) (-4dBs), High impedance (RCA pin jack)
Video Audio Output terminal
Video
1V(p-p) 75(RCA pin jack)
Audio(L/R)
500mV(rms) (-4dBs), High Impedance (RCA pin jack)
Aerial Input Terminal
75unbalanced, Coaxial
Headphone jack
Stereo mini jack (3.5mm )
AV Compu Link terminal
AV Compu Link, mini jack (3.5mm )
Remote Control Unit
RM-C112 (AA/R06/UM3 dry battery×2)
Design & specifications are subject to change without notice.


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No.51750
AV-25PS
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, screw
"heads, 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.51750
AV-25PS
4
FEATURES
" By preference, users can select the picture size from REGULAR,
ZOOM, 16:9 modes.
" The TELETEXT SYSTEM has a built-in FASTEXT and WST
system.
" Because this TV unit corresponds to multiplex broadcast, users
can enjoy music programs and sporting events with live realism.
In addition, BILINGUAL programs can be heard in their original
language.
" Users can make fun to connect the Digital Video Disk player by
using the component video signal input terminal.
" Built-in ECO (ECONOMY, ECOLOGY) MODE.
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.
" I2C Bus controls the many ICs which have various functions each
other.
I
2C BUS CONTROL SYSTEM CHART
IC1701
MICRO
COMPUTER
IC1701
MICRO
COMPUTER
IC1301
VIDEO
CHROMA
IC1301
VIDEO
CHROMA
IC1501
DEF CTRL
IC1501
DEF CTRL
IC1201
SRT
IC1201
SRT
IC8801
LED CTRL
IC8801
LED CTRL
IC301 [0S]
DIGI COMB
IC301 [0S]
DIGI COMB
IC101 [0S]
AV SW
IC101 [0S]
AV SW
IC603 [0S]
MSP
IC603 [0S]
MSP
IC1702
MEMORY
IC1702
MEMORY
SCL2 / SDA2
SCL3 / SDA3
TU1001
TUNER
TU1001
TUNER
SCL1 / SDA1


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No.51750
AV-25PS
5
FUNCTIONS
Headphone jack
TV/VIDEO
POWER
Video-4 terminal
ECO sensor
Main POWER SW
OK
Remote control sensor
Channel -/+ (MENU UP/DOWN)
ECO
Volume -/+ (MENU LEFT/RIGHT)
ON TIMER
Video-1 terminal (S,V,L,R)
Video-2 terminal (V,L,R)
Video-3 terminal (V/Y,Cb,Cr,L,R)
Output terminal (V,L,R)
AV COMPULINK terminal
Aerial socket
POWER
TV/TELETEXT(TELETEXT CONTROL)
COLOUR
TV/VIDEO
DISPLAY
ZOOM
MENU UP/DOWN
MENU LEFT/RIGHT
OK
AUTO VNR
AAC
PICTURE MODE
SPATIALIZER
CHANNEL
CHANNEL SCAN
CHANNEL +/-
VOLUME +/-
MUTING
18
FRONT PANEL
REAR TERMINAL
REMOTE CONTROL UNIT(RM-C112)