JVC AV-27920 User manual

JVC
CONTENTS
| | SPECIFICATIONS re 2
@ SAFETY PRECAUTIONS -*:<**2**-*22*% Ce ee 3
@ FEATURES °-«--++-e +22 e022 eee ene ey 4
i | DIFFERENCE LIST OF MAIN PARTS i ee 4
a OPERATING INSTRUCTIONS ee ee ee ee ay 5
i] SPECIFIC SERVICE INSTRUCTIONS ee ra Glatelo\bidsa ale ake Sierra 6
i | SERVICE ADJUSTMENTS ee 10
% STANDARD CIRCUIT DIAGRAM (APPENDED) «+ ---+++--crereeeee reer e reese ee ee eee es 2-1
i] PARTS LIST ee ry TUTE ECELELET TEE er 25 F
COPYRIGHT © 1998 VICTOR COMPANY OF JAPAN, LTD.
No. 51370
Mar. 1998

AV-27920
SPECIFICATIONS
Dimensions (W x H x D}
Mass
TV RF System
Color Sound System
TV Receiving Channels and Frequency
VL Band
VH Band
UHF Band
CATV Receiving Channels and Frequency
Low Band
High Band
Mid Band
Super Band
Hyper Band
Ultra Band
Sub Mid Band
TV/ICATV Total Channel
Intermediate Frequency
Video IF Carrier
Sound JF Carrier
Color Sub Carrier
Power Input
Power Consumption
Picture Tube
High Voltage
Audio Power Output
Input
Video Input
Audio Input
Antenna Terminal
Remote Control Unit
25-3/4" x 23-3/8" x 19-1/2” / 65.4em x 59.3cm x 49.4cm
68.5 ibs / 31.1 kg
CCIR(M)
(Multi Channel Sound)
(02~06) 54MHz~88MHz
(07~13) 174MHz~216MHz
(14~69) 470MH2~806MHz
(02~06, A-8) by (02~06&01)
(07~13) by (07~13)
(A~1) by (14~22)
(J~W) by (23~36)
(W+1~W+28) by (37~64)
(W+29~W+84) by (65~125)
(A8, A4~A1) by (01, 96~99)
180 Channels
(64MHz~804MHz)
45.75MHz
41.25MHz (4.5MHz)
3.58MHz
120V AC, 60Hz
113W (US) /1.8A (CA)
27” (68cm) Measured Diagonally
29kV+1kV (at zero beam current)
2" x 3-1/2" /5 x 9em
Oval type x 2
1.2W x2
1Vp-p, 752 (RCA pin jack)
500mVrms ( -4dBs ), High Impedance (RCA pin jack)
Low impedance (400Hz when modulated 100%)
(RCA pin jack)
752 (VHF/UHF) Terminal, F-Type Connector
RM-C754-1C
(AA/R6/UM-3 battery x 2)
Design & specification are subject to change without notice.
No.51370

AV-27920
SAFETY PRECAUTIONS
1. The design of this product contains special hardware, many 10. Isolation Check
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.
(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
2. Alterations of the design or circuitry of the products should not be be sure the product is safe to operate without danger of electrical
made. Any design alterations or additions will void the shock.
manufacturer's warranty and will further relieve the manufacturer (1) Dielectric Strength Test ; !
of responsibility for personal injury.or property damage resulting The isolation between the AC primary circuit and all metal parts i
therefrom. exposed to the user, particularly any exposed metal part having a i
3. Many electrical and mechanical parts in the products have return path to the chassis should withstand a voltage of 1100V i
special safety-related characteristics. These characteristics are AC (r.m.s.) for a period of one second. I
often not evident from visual inspection nor can the protection (... . Withstand a voltage of 1100V AC (r.m.s.) to an appliance i
afforded by them necessarily be obtained by using replacement rated up to 120V, and 3000V AC (r.m.s.) to an appliance rated i
components rated for higher voltage, wattage, etc. Replacement 200V or more, for a period of one second.)
parts which have these special safety characteristics are This method of test requires a test equipment not generally found i
identified in the parts list of Service manual. Electrical in the service trade.
components having such features are identified by shading (2) Leakage Current Check i
on the schematics and by (A\) on the parts list in Service Plug the AC line cord directly into the AC outlet (do not use a line ;
manual. The use of a substitute replacement which does not isolation transformer during this check.). Using a “Leakage :
have the same safety characteristics as the recommended Current Tester", measure the leakage current from each exposed j
replacement part shown in the parts list of Service manual may metal part of the cabinet, particularly any exposed metal part i
cause shock, fire, or other hazards. having a return path to the chassis, to a known good earth ground :
4. Use isolation transformer when hot chassis. (water pipe, etc.). Any leakage current must not exceed 0.5mA (
The chassis and any sub-chassis contained in some products are AC (r.m.s.). i
connected to one side of the AC power line. An isolation However, in tropical area, this must not exceed 0.2mA AC
transformer of adequate capacity should be inserted between the (r.m.s.).
product and the AC power supply point while performing any @ Alternate Check Method
service on some products when the HOT chassis is exposed. Plug the AC line cord directly into the AC outlet (do not use a line
5. Don't short between the LIVE side ground and ISOLATED isolation transformer during this check.). Use an AC voltmeter
(NEUTRAL) side ground or EARTH side ground when having 1000 ohms per volt or more sensitivity in the following
repairing. manner. Connect a 15009 10W resistor paralleled by a 0.15 4 F
Some
model's
power
circuit:
is
partly
different
in
the
GND.
The
AC-type
capacitor
between
an
exposed
metal
part
and
a
known
difference
of
the
GND
is
shown
by
the
LIVE
:
(.L)
side
GND,
the
good
earth
ground
(water
pipe,
etc.).
Measure
the
AC
voltage
ISOLATED(NEUTRAL)
:
(+)
side
GND
and
EARTH
:
(@)
side
across
the
resistor
with
the
AC
voltmeter.
Move
the
resistor
GND. Don't short between the LIVE side GND and connection to each exposed metal part, particularly any exposed
ISOLATED(NEUTRAL)
side
GND
or
EARTH
side
GND
and
metal
part
having
a
return
path
to
the
chassis,
and
measure
the
never measure with a measuring apparatus (oscilloscope etc.) the AC voltage across the resistor. Now, reverse the plug in the AC
LIVE
side
GND
and
ISOLATED(NEUTRAL)
side
GND
or
outlet
and
repeat
each
measurement.
Any
voltage
measured
must
‘EARTH side GND at the same time. not exceed 0.75V AC (r.m.s.). This corresponds to 0.5mA AC
If above note will not be kept, a fuse or any parts will be broken, (r.m.s.). :
6. if any repair has been made to the chassis, it is recommended However, in tropical area, this must not exceed 0.3V AC (r.m.s.).
that
the
B1
setting
should
be
checked
or
adjusted
(See
This
corresponds
to
0.2mA
AC
(r.m.s.).
i
ADJUSTMENT OF B1 POWER SUPPLY). i
7. The high voltage applied to the picture tube must conform with AC VOLTMETER |
that specified in Service manual. Excessive high voltage can (HAVING 1000 2/V, i
cause an increase in X-Ray emission, arcing and possible OR MORE SENSITIVITY) ;
component damage, therefore operation under excessive high GOOD |
voltage conditions should be kept to a minimum, or should be padi i
prevented. If severe arcing occurs, remove the AC power i
immediately and determine the cause by visual inspection PLACE THIS PROBE ;
(incorrect installation, cracked or melted high voltage harness, ON EACH EXPOSED i
poor soldering, etc.). To maintain the proper minimum level of soft 15002 10W METAL PART
X-Ray emission, components in the high voltage circuitry f
including the picture tube must be the exact. replacements or 41. High voltage hold down circuit check.
alternatives approved by the manufacturer of the complete After repair of the high voltage hold down circuit, this circuit shail
8 Poe Seek high voltage by drawing an arc. Use a high voltage Be eee Pe Sen:
meter or a high voltage probe with a VTVM. Discharge the picture pees OM TiO Se CIOEe We Heat yates HOKIAO WN Creu: i
tube before attempting meter connection, by connecting a clip :
lead to the ground frame and connecting the other end of the lead This mark shows a fast POWER CORD
through a 10k92 2W resistor to the anode button. operating fuse, the REPLACEMENT WARNING.
9. When service is required, observe the original lead dress. Extra letters indicated below Connecting the line side of
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 manufacturers replacement
components.
No.51370
show the rating. power cord to" @" mark side.

AV-27920
FEATURES
@ New chassis design enables use of a single board with simplified
circuitry. ;
@ Provided with miniature tuner (TV/CATV).
Multifunctional remote control permits picture adjustment.
@ Adoption of the CHANNEL GUARD function prevents the specific
channels from being selected, unless the “ID number’ is key in.
@ (°C bus control utilizes single chip ICs.
Built-in HYPER-SURROUND system.
@ Adoption of the VIDEO STATUS function.
Adoption of the ON/OFF TIMER function.
With 752 V/U in common (F-Type) ANT Terminal.
SLEEP TIMER for setting in real time.
Closed-caption broadcasts can be viewed.
S-VIDEO input terminal for taking best advantage of Super VHS.
Audio Video input terminal.
Variable Audio output terminal.
Built-in MTS system.
DIFFERENCE LIST OF MAIN PARTS
AV-27920(US) — AV-27920(CA)
Parts Name
INST BOOK (FRENCH) ; x LCT0108-001B-A
SVC CENTER LIST x BT-20071B-Q
REGI. CARD BT-51006-1Q x
WARRANTY CARD x BT-52002-1Q
4 No.51370

AV-27920
OPERATING INSTRUCTIONS
e The operating instructions are the same as for C-20910(US&CA)/AV-20920(US&CA)/AV-20921(US&CA) (No.51364),
Therefore, please refer to the C-20910(US&CA)/AV-20920(US&CA)/AV-20921(US&CA)(N0.51364) SERVICE MANUAL for detailed
instructions.
@ REMOTE CONTROL UNIT [RM-C754-1C]
CHANNEL
MUTING VOLUME
© €Ty
MENU exit
on. O
@ 5)
@
@ FRONT PANEL
WMENU — CHANNEL + —— VOLUME + POWER
4OPERATE >
M@ REAR PANEL
No.51370 5
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AV-27920
SPECIFIC
SERVICE
INSTRUCTIONS
DISASSEMBLY PROCEDURE
REMOVING THE REAR COVER
4. Unplug the power supply cord.
2. Remove the 7 screws marked @ and 2 screws marked ® as
shown in Fig.1.
3. Withdraw the REAR COVER toward you.
[CAUTION]
@ When reinstalling the rear cover, carefully push it inward after
inserting the MAIN PWEB into the rear cover groove.
REMOVING THE MAIN PW BOARD
® After removing the rear cover.
1. Pick this side of the MAIN PWB and raise one slightly, take off
the PWB stopper marked © from the cabinet bottom.
2. Pull out the MAIN PWB as it is.
(If necessary, take off the wire clamp and connectors, etc.)
REMOVING THE SPEAKER
@ After removing the MAIN PW board.
1. Remove the 2 screws marked © as shown in Fig.1.
2. Withdraw the speaker backward.
3. Follow the same steps when removing the other hand speaker.
CHECKING THE MAIN PW BOARD
1. To check the back side 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
back side 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.
6 No.51370

AV-27920
FRONT CABINET
CRT SOCKET PWB
(Within MAIN PWB)
SPEAKER
MAIN PWB
ee
Ren
A
eR
NET
MERGE
SEA
OL
Se
SA
ASO
nar
umes
termes
renee
an
gn
REAR COVER
SPEAKER
Fig.1
No.51370

AV-27920
MEMORY IC REPLACEMENT
1. Memory IC
This model use a memory IC.
This memory IC stores data for proper operation of the video and deflection circuits.
When replacing, be sure to use an IC containing this (initial value) data.
2. Memory IC replacement procedure
— ae
Switch off the power and disconnect the power cord from the outlet.
(2) Replace the memory IC
Initial value must be entered into the new IC.
(3) Power on
Connect the power cord to the outlet and switch on the power.
(4) System constant check and setting
1) Simultaneously press the DISPLAY key and VIDEO STATUS key of
the remote control unit.
2) The SERVICE MENU screen of Fig.1 is displayed.
3) While the SERVICE MENU is displayed, again simultaneously press
[SERVICE MENU J
PICTURE SOUND
the DISPLAY and VIDEO STATUS keys to display the Fig.2 SYSTEM GAME
CONSTANT screen. LOW LIGHT HIGH LIGHT
RF AFC CHK
4) Refer to the SYSTEM CONSTANT table and check the setting items.
Where these differ, select the setting item with the MENU UP/DOWN
key and adjust the setting with the MENU LEFT/RIGHT keys. (The
letters of the selected item are displayed in yellow.)
5) After adjusting, release the MENU LEFT/RIGHT key to store the setting
value.
6) Press the EXIT key twice to return the normal screen.
vco( PC BUS CTRL
SELECT BY aij &xiTBY
OPERATE BY Sj (EXIT)
[ SYSTEM CONSTANT
MTS > YES
VARI.OUT > YES
(5) Receive channei setting
Refer to the OPERATING INSTRUCTIONS(USER'S GUIDE) and set the
2 GAME : YES
receive channels (Channels Preset) as described. SURROUND : YES
S-VIDEO > YES
M37272M8-4SP
SELECT BY fal [yi EXIT BY
OPERATE BY ie! EXIT
(6) User settings
Check the user setting items according to Table 2.
Where these do not agree, refer fo the OPERATING INSTRUCTIONS
(USER'S GUIDE) and set the items as described.
(7) SERVICE MENU setting
Verify what to set in the SERVICE MENU, and set whatever is
necessary.(Fig.1) Refer to the SERVICE ADJUSTMENT for setting.
8 No.51370

AV-27920
Setting content
TABLE 1 (System Constant setting)
ee
TABLE 2. (User setting value)
Setting item . Setting value
1. Use remote controller keys
POWER
CHANNEL
CHANNEL PRESET
VOLUME
DISPLAY
SLEEP TIMER
VIDEO STATUS
CLOSED CAPTION
HYPER SURROUND
2. Setting of MENU
TINT
COLOR
PICTURE
BRIGHT
DETAIL
NOISE MUTING
SET VIDEO STATUS
BASS
TREBLE
BALANCE
MTS
TV SPEAKER
SET CLOCK
ON/OFF TIMER
CHANNEL SUMMARY
SET LOCK CODE
AUTO TUNER SETUP
BACKGROUND
CLOSED CAPTION
LANGUAGE
OFF
CH 02
See OPERATING INSTRUCTIONS.
10
OFF
O(OFF)
STANDARD
OFF(CC1/T1)
OFF
CENTER
CENTER
CENTER
CENTER
CENTER
ON
ALL CENTER
CENTER
CENTER
CENTER
STEREO
ON
Unnecessary to set
NO
SET OPTIONALLY
Unnecessary to set
TUNER MODE : AIR
BLACK
CAPTION: CC1 TEXT: T1
ENG
No.51370

AV-27920
SERVICE ADJUSTMENT
ADJUSTMENT PREPARATION:
1. You can make the necessary adjustments for this unit with
either the Remote Control Unit or With the adjustment
tools 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 which set the screen to its optimum condition may
differ from the initial settings.
3. Turn on the power for set and test equipment before use, and
start the adjustment procedures after waiting at least 30
minutes.
4. Make sure that AC power is turned on correctly.
ADJUSTMENT EQUIPMENT
DC voltmeter (or digital voltmeter)
Oscilloscope
Signal generator (Pattern generator) [NTSC]
Remote control unit
. TV audio multiplex signal generator.
. Frequency counter
OnRYWN >
ADJUSTMENT LOCATIONS
VOL+ VOL- CH+ CH MENU
TP-12B
T1341 CW
TP-91 ee
(B1)
TP-E
(1)
Lav IN our _]
S-IN
1C702
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 adjustment - variable resistors, transformers,
condensers, etc.
7. Presetting before adjustment.
Unless otherwise specified in the adjustment instructions,
preset the following functions with the remote control unit:
e@ VIDEO STATUS STANDARD
e@ BASS, TREBLE, CENT!
BALANCE ENTER
ADJUSTMENT ITEMS
B1
POWER
WHITE
BALANCE
SUPPLY
(Low
Light)
WHITE
BALANCE
IF
VCO
ead
(High
Light)
RF. AGC SUB BRIGHT
FOCUS SUB CONTRAST
V. SIZE SUB COLOR
H. POSITION SUB TINT
Adjustment items
MTS INPUT
LEVEL check
MTS STEREO
vco
MTS SAP VCO
MTS FILTER check
MTS
SEPARATION
c=]
STEREO[S]
MAIN PWB
CRT SOCKET PWB) '2P
(Within MAIN PWB ASS'Y)
(SOLDER SIDE)
UPPER : FOCUS
LOWER : SCREEN
CRT EARTH
(BRAIDED ASS'Y)
410 No.51370

AV-27920
BASIC
OPERATION
OF
SERVICE
MENU
1.
2.
3
Operate
the
SERVICE
MENU
with
the
REMOTE
CONTROL
UNIT.
In
general,
8
basic
setting
{adjustments)
items
or
verifications
are
performed
in
the
SERVICE
MENU.
(1)
PICTURE-++++++++----eeee
eee
This
sets
the
setting
values
(adjustment
values)
of
the
VIDEO/CHROMA
and
DEFLECTION
circuits.
(2)
SOUND
+++
+++
eee
eee
seen
+++
This
sets
the
setting
values
(adjustment
values)
of
the
AUDIO
circuit.
(3)
GAME-
+++
+
+e
reece
eee
cece
eee
This
is
used
when
the
GAME
MODE
is
adjusted.
(4)
LOW
LIGHT
-+-+-++--++eeeeeeee
This
sets
the’
setting
values
(adjustment
values)
of
the
WHITE
BALANCE
circuit.
(5)
HIGH
LIGHT
-+-+-+---es
eee
eeee
This
sets
the
setting
values
(adjustment
values)
of
the
WHITE
BALANCE
circuit.
(6)
RF
AFC
CHK:
++
+--+
eee
cere
eee
This
is
used
when
the
IF
VCO
is
adjusted.
[Do
not
adjust]
(7)
VCO
(CW)
+
rrr
e
rere
e
eee
e
ee
eens
This
is
used
when
the
IF
VCO
is
adjusted.
(8)
120
BUS
CTRL
-+++
+e
eee
reer
eee
This
is
used
when
ON/OFF
of
the
I2C
BUS
CTRL
is
set.
[Fixed
ON]
.
Basic
Operations
of
the
SERVICE
MENU
(1)
How
to
enter
the
SERVICE
MENU.
Press
the
DISPLAY
key
and
VIDEO
STATUS
key
of
the
remote
control
unit
at
the
same
time
to
enter
the
SERVICE
MENU
screen
@
shown
in
figure
page
later.
(2) SERVICE MENU screen selection
Press
the
UP
/
DOWN
key
of
the
MENU
to
select
any
of
the
following
items.
_
(The
letters
of
the
selected
items
are
displayed
in
yellow.)
@ PICTURE . @ SOUND
@ GAME
@
LOW
LIGHT
@
HIGH
LIGHT
@
RF
AFC
CHK
@
vco(cw)
@
’C
BUS
CTRL
(3)
Enter
the
any
setting
(
adjustment
)
mode
@
PICTURE
and
SOUND
mode
1)
If
select
any
of
PICTURE
or
SOUND
items,
and
the
LEFT
/
RIGHT
key
is
pressed
from
SERVICE
MENU
(
MAIN
MENU
),
the
screen
@
will
be
displayed
as
shown
in
figure
page
later.
2)
Then
the
UP
/
DOWN
key
is
pressed,
the
PICTURE
mode
screen
@®
or
the
SOUND
mode
screen
@
is
displayed,
and
the
PICTURE
or
SOUND
setting
can
be
performed.
®
GAME,
LOW
LIGHT,
HIGH
LIGHT,
RF
AFC
CHK,
VCO
(CW)
and
12C
BUS
CTRL
mode
1)
If
select
any
of
GAME
/
LOW
LIGHT
/
HIGH
LIGHT
/
RF
AFC
CHK/
VCO
(CW)
/I2C
BUS
CTRL
items,
and
the
LEFT
/
RIGHT
key
is
pressed
from
SERVICE
MENU
(
MAIN
MENU),
the
screens
©
©
@
@
©
will
be
displayed
as
shown
in
figure
page
later.
2)
Then
the
settings
or
verifications
can
be
performed.
. .
No.51370
11
ca a mee tA TEE ESET SES OT OS os tere neta eearcinpecnaeer seamcmnsem renee

AV-27920
® SERVICE MENU (MAIN MENU) @) SCREEN @) PICTURE MODE
SERVICE MENU
PICTURE SOUND
GAME
LOW LIGHT HIGH LIGHT
RF AFC CHK
YCO(CW) @C BUS CTRL
1. BRIGHT
STATUS
SELECT BY EXIT BY
OPERATEBY [4] [b] [ExT]
SELECT BY {al [¥] SELECT BY
OPERATE BY
@ SOUND MODE
HIGH LIGHT
1. BALANCE oe
STATUS eee
SELECT BY [a] m7 EXIT BY
OPERATEBY — [4] [P] (er) |
SELECT BY fal [¥] EXIT BY
OPERATEBY — [4] [P] (ExT)
© voc (cw) MODE © GAME MODE
TOO HIGH TINT
ABOVE REFERENCE COLOR
BELOW REFERENCE PICTURE
TOO LOW BRIGHT
SYNC : YES DETAIL
SELECT BY [a] [¥] EXIT BY
OPERATEBY — [4] [P]
(0 Ic BUS CTRL MODE
{FIXED ON] © LOW LIGHT MODE
42¢ BUS
OPERATEBY [4] [b]
12
No.51370

AV-27920
;
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:
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‘
g
i
i
(4) Setting method
1) UP/DOWN key of the MENU
Select the SETTING ITEM.
2) LEFT / RIGHT key of the MENU
Setting(adjust) the SETTING VALUE of the SETTING ITEM. ry” 1. BRIGHT J eee
When the key is released the SETTING VALUE will be stored i STATUS i
(memorized).
SELECT
BY
[al
{¥]
EXIT
BY
|
|
INITIAL
:
Tal SETTING VALUE Ly
3) EXIT key Ly LONER. fall Y pd
.
SETTING
VALUE
i
Returns to the previous screen. ae PICTURE MODE
ITEM }
(5) Releasing SERVICE MENU
1) After returning to the SERVICE MENU upon completion of the setting
(adjustment) work, press the EXIT key again.
1. BALANCE Sd
STATUS appt:
SELECT BY _— [a] [¥] EXIT BY
* The settings for LOW LIGHT and HIGH LIGHT are described in the WHITE OPERATE BY [4] [>]
BALANCE page of ADJUSTMENT.
SOUND MODE
* The setting for VCO(CW) are described in the IF VCO page of ADJUSTMENT.
GAME
TINT baal GDRIVE ee
[Re letter of the selected ] ‘sivsdstassincsen Lab
COLOR = 4 BORIVE
Items are displayed in yellow. PICTURE 46
BRIGHT
DETAIL =
SELECT BY [al [¥] EXIT BY
OPERATEBY [4] [b]
GAME MODE
No.51370 13

AV-27920
INITIAL SETTING VALUE OF SERVICE MENU
1.
2.
Adjustment of the SERVICE MENU is made on the basis of the initial setting values; however, the new setting values which set the screen
in its optimum condition may differ from the initial setting.
Do not change the initial setting values of the setting (Adjustment) items not listed in “ADJUSTMENT” .
@ PICTURE MODE
+
The four setting items in the video mode No.8 EXT BRI., No.9 EXT PIC., No.12 EXT TINT and No.13 EXT COL. are linked to the items in
the TV MODE No.1 BRIGHT, No.2 PICTURE, No.6 TINT and No.7 COLOR, respectively. When the setting items in the TV mode are
adjusted, the values in the setting items in the video mode are revised automatically to the same values in the TV mode.(The initial setting
values given in () are off-set values.)
~> When the four items (No.8, 9, 12 and 13) are adjusted in the video mode, the setting values in each item are revised independently.
No. | Setting (Adjustment) items
Variable range initial setting value
BRIGHT
PICTURE
WPS(WHITE PEAK SUPPRESSOR)
TV DTL(TV DETAIL)
TV BPF(TV B.P.FILTER)
TINT
COLOR
EXT. BRI.(EXT.BRIGHT)
EXT. PIC.(EXT.PICTURE)
EXT. DTL(EXT.DETAIL)
EXT BPF(EXT.B.P.FILTER)
EXT. TINT
EXT. COL.(EXT.COLOR)
V. SIZE
V. CENT.(V.CENTER)
H. POS.(H.POSITION)
OSD HP (OSD H POSITION)
OSD VP (OSD V POSITION)
H. AFC
BLANKING
Y. TRAP
RF. AGC
PIF VCO
TWEXT
SoM MN Ola aA wD =
oO Oo 90 Oj;j0 oO oO AO OI100
@ GAME MODE
14
Setting (Adjustment) item :
Variable range initial setting value
0
0
TINT
COLOR
PICTURE
BRIGHT
DETAIL
-10
5
+5
G DRIVE
B DRIVE
No.51370

AV-27920
@
SOUND
MODE
4
No.
|
Setting
(Adjustment)
item
¥
Variable
range
Initial
setting
value
BALANCE
NOISE ;
IN LEVEL (INPUT LEVEL) ;
FH MON. (FM MONITOR)
PILOT (PILOT CANCELER)
FILTER
LOW SEP. (LOW SEPARATION)
HI SEP. (H] SEPARATION)
5FH MON. (SFH MONITOR)
SAP VCO
IN GAIN (INPUT GAIN)
FIL. OFF.
@ LOW LIGHT MODE
Setting
(Adjustment)
item
Variable
range
initial
setting
value
R CUTOFF 20
G CUTOFF ; 20
B CUTOFF 20
@® HIGH LIGHT MODE
Setting
(Adjustment)
item
Variable
range
initial
setting
value
a
|
G
DRIVE
0
~
255
B
DRIVE
QO
~
255
@
RF
AFC
CHK
MODE
Setting
(Adjustment)
item
Variable
range
initial
setting
value
i
RF
AFC
ON
/
OFF
ON
(
DO
NOT
)
ADJUST
FINE 77 ~ +77 +x x
® |?C BUS CTRL MODE
Setting
(Adjustment)
item
Variable
range
initial
setting
value
No.51370 15 |

AV-27920
m ADJUSTMENTS
B1 POWER SUPPLY
Measuring
Test
point
Adjustment
part
Description
;
instrument
|
ICheckof __| DC Voltmeter | TI Voltmeter | TP-91 (B1) . Receive a monoscope pattern ~ |4. Receiveamonoscope patternsignal. #8 |
; Connect the DC Voltmeter to TP-91 (B1) and TP-E(L).
TP-E({.L)
3. Confirm that the voltage is DC134V ay
ADJUSTMENT OF VIDEO / DEF. CIRCUIT
IF VCO Signal CW TRANSF. (1131) 11. Receive a NTSC broadcast. (use channels without offset
adjustment generator
frequency).
Select the VCO(CW) mode from the SERVICE MENU.
Confirm the color change (yellow) from “TOO HIGH” to
“TOO LOW” by CW TRANSF. and “SYNC : YES” being
shown on the screen. Then, adjust CW TRANSF. until
“BELOW REFERENCE” mark turns yellow and confirm
TOO HIGH again “ SYNC: YES” being shown on the screen.
ABOVE REFERENCE ;
BELOW REFERENCE YELLOW
TOO LOW
[VcO(CW)] MODE
SYNC : YES
RF. AGC No.22 RF AGC . Receive a broadcast.
adjustment Select “No.22 RF AGC’ of the PICTURE MODE.
Press the MUTE key and turn off color.
With the MENU LEFT key, get noise in the screen picture. (0
side of setting value)
Press the MENU RIGHT key and stop when noise disappears
from the screen.
Change to other channels and make sure that there Is no
irregularity.
Press the MUTE key and get color out.
FOCUS
Receive a crosshatch signal.
adjustment
While looking at the screen, adjust FOCUS VR so that the
vertical and horizontal lines will be clear and in fine detail.
Make sure that the picture is in focus even when the screen
gets darkened.
16 No.51370

AV-27920
instruments
V.SIZE Signal No.14 V.SIZE
Adjustment | generator
Screen size
Picture
size
100%
Picture size 100% |
H.POSITION | Signal No.16 H.POS
Adjustment | generator
Receive a crosshatch signal.
Select No.14 V.SIZE in the PICTURE MODE.
Set the initial setting value of No.14 V.SIZE with the LEFT /
RIGHT key of the MENU.
Adjust No.14 V.SIZE until the vertical screen size is 92%.
Receive a crosshatch signal.
Select the No.16 H.POS of the PICTURE MODE.
Set the initial setting value of the No.16 H.POS with the LEFT /
RIGHT key of the MENU.
Adjust the No.16 H.POS until the screen will be horizontally
centered.
No.51370 17

AV-27920
Measuring Test point Adjustment part Description
instruments
WHITE
BALANCE
(Low Light)
Adjustment
WHITE
BALANCE
(High Light)
Adjustment
18
BRIGHT
R. CUTOFF
G. CUTOFF
B. CUTOFF
SCREEN VR
[In FBT]
Signal
generator
[LOW LIGHT] MODE
G CUTOFF
BRIGHT
R CUTOFF B CUTOFF
BRIGHT [<<] [>]
REMOTE CONTROL UNIT
H.LINE ON H.LINE OFF
RCUTOFF A GCUTOFFA
2 s
RCUTOFF ¥ G CUTOFF ¥
G. DRIVE
B. DRIVE
Signal
generator
[HIGH LIGHT] MODE
B DRIVE
HIGH LIGHT $
ak ek
G DRIVE
EXIT BY
No.51370
Receive a monoscope pattern signal.
Select the {LOW LIGHT] MODE from the SERVICE MENU.
Set the initial setting value of BRIGHT with the LEFT /
RIGHT key of the remote control unit.
Set the initial setting value of R CUTOFF, G CUTOFF and
B CUTOFF with the @ to @ key of the remote control
unit.
Display a horizontal line by pressing the @key of the
remote control unit.
Turn the screen VR ail the way to the left.
Turn the screen VR gradually to the right from the left until
either one of the red, blue or green colors appears slightly.
Adjust the two colors which did not appear until the a
horizontal line that is displayed becomes white using the @
to © keys of the remote contro! unit.
Turn the screen VR until the first horizontal line is displayed
slightly.
. Press the @ key to return to the regular screen.
The @ EXIT key is the cancel key for the WHITE
BALANCE.
Receive a monoscope pattern signal.
Select the [HIGH LIGHT] MODE in the SERVICE MENU.
Set the initial setting value of G DRIVE and B DRIVE with
the 6, ©, and @) keys of the remote control unit.
Adjust the screen until it becomes white using the ©, ©,
and @ keys of the remote control unit.
The @ (EXIT) key is the cancel key for the WHITE
BALANCE.
Remote Control Unit
@ key : H.LINE ON
@ key : H.LINE OFF
@ key : EXIT
@ key :GDRIVE A
© key :BDRIVE A
key :GDRIVE V
© key :BDRIVE ¥

| Aaustment part | | Aaustment part |
Measuring Test point
instruments
|)
=
1
BRIGHT
Adjustment
SUB
CONT-
RAST
Adjustment
SUB
COLOR
Adjustment
ar
7
ae
7
eee OF MTS CIRCUIT
Measuring
Test
point
instrument
=
Signal
[MPX]
No.4
FH
MON.
generator Connector.
[2] pin RTV |No.5 ST VCO
SUB TINT
Adjustment
| Aducent part part
MTS INPUT
LEVEL
Frequency
counter
adjustment
No.51370
1
2
AV-27920
Description
Receive a broadcast.
:
Select
No.1
BRIGHT
of
the
PICTURE
MODE.
3.
Set
the
initial
setting
value
of
the
No.1
BRIGHT
with
the
LEFT
/
RIGHT
key
of
the
MENU.
4.
If
the
brightness
is
not
best
with
the
initial
setting
value,
make
fine
adjustment
of
the
No.1
BRIGHT
until
you
get
the
optimum brightness.
Receive a broadcast.
.
Select
No.2
PICTURE
of
the
PICTURE
MODE.
3.
Set
the
initial
setting
value
of
the
No.2
PICTURE
with
the
LEFT
/
RIGHT
key
of
the
MENU.
4.
Ifthe
contrast
is
not
best
with
the
initial
setting
value,
make
fine
adjustment
of
the
No.2
PICTURE
until
you
get
the
optimum
contrast.
. Receive a broadcast.
2.
Select
No.7
COLOR
of
the
PICTURE
MODE.
3.
Set
the
initial
setting
value
of
the
No.7
COLOR
with
the
LEFT
/
RIGHT
key
of
the
MENU.
4.
If
the
color
is
not
best
with
the
initial
setting
value,
make
fine
adjustment
of
the
No.7
COLOR
until
you
get
the
optinum
color.
. Receive a broadcast.
2.
Select
No.6
TINT
of
the
PICTURE
MODE.
3.
Set
the
initial
setting
value
of
the
No.6
TINT
with
the
LEFT
/
RIGHT
key
of
the
MENU.
4.
If
the
tint
is
not
best
with
the
initial
setting
value,
make
fine
adjustment
of
the
No.6
TINT
until
you
get
the
optimum
tint.
Description
1.
Select
the
“No.3
IN
LEVEL”
of
the
SOUND
MODE.
2.
Verify
that
the
“No.3
IN
LEVEL”
is
set
at
its
initial
setting
value.
Receive
a
RF
signal
(nonmodulated
sound
signal)
from
the
antenna
terminal.
Select
the
“No.4
FH
MON.”
of
SOUND
MODE,
and
change
the
setting
value
from
0
to
1.
Connect
the
Frequency
Counter
to
pin
[2]
of
[MPX]
connector.
Select the “No.5 ST VCO”.
Set
the
initial
setting
value
of
the
“No.5
ST
VCO”
with
the
LEFT/RIGHT
key
of
the
menu.
Adjust
the
“No.5
ST
VCO"
so
that
the
Frequency
Counter
will
display
15.73kHz+0.1kHz.
Select
the
“No.4
FH
MON."
of
the
SOUND
MODE,
and
reset
the
setting
value
from
1
to
0.
19
t
i
t
i
:
i

AV-27920
Measuring | Test point | Adjustment part Description
instrument
MTS SAP Signal [MPXx] No.10 5FH MON. . Receive a RF signal (non modulated sound signal) from the
vco generator antenna terminal.
adjustment 2. Connect between pin [4) of [MPX] connector and GND (Pin
[3] of [MPX] connector) through 1MQ Resistor.
3. Select the “No.10 5FH MON.” of the SOUND MODE, and reset
the setting value from 0 to 1. ‘
4. Connect the Frequency Counter to pin [2) (R.OUT) of [MPX]
connector.
5. Select the “No.11 SAP VCO”.
6. Set the initial setting value of “No.11 SAP VCO” with the
LEFT/RIGHT key of the menu.
7. Adjust the “No.11 SAP VCO” so that the Frequency Counter
will display 78.67kKHz-+0.5kHz.
8. Select the “No.10 SFH MON.” of the SOUND MODE, and reset
the setting value from 1 to 0.
Connector
[4]
pin
SDA|No.11
SAP
VCO
[3] pin GND
[2] pin RTV
Frequency
counter
. Select the “No.7 FILTER” of the SOUND MODE.
2. Verify that the “No.7 FILTER’ is set at its initial setting value.
MTS FILTER
check
No.7 FILTER
MTS No.8 LOW SEP,
SEPARATION
adjustment
TV audio
multiplex
signal
generator
{MPX]
Connector
{1]
pin
LTV
No.3
Hj
SEP.
(2} pin RTV
Input a stereo L signal (300Hz) from the TV audio multiplex
signal generator to the antenna terminal.
2. Connect an oscilloscope to pin [1] (L OUT) of [MPX]
connector, and display one cycle portion of the 300Hz signal.
3. Change the connection of the oscilloscope to pin [2] (R OUT)
Oscilloscope of {MPX] connector, and enlarge the voltage axis.
4. Select the “No.8 LOW SEP.” of the SOUND MODE.
5. Set the initial setting value of the “No.8 LOW SEP.” with the
LEFT/RIGHT key of the menu.
6. Adjust the “No.8 LOW SEP.” so that the stroke element of the
300Hz signal will become minimum.
7. Change the signal to 3kHz, and similarly adjust the “No.9 HI
SEP.”.
L-Channel R-Channel
signal waveform crosstalk portion
} Minimum
ee ———
20 . No.51370