NEC JC-1401P3A User manual

Sco
HE
MODEL
JC-1401P3A
230
ell
|
MULTISYNC
COLOR
МОМТОВ
..
SERVICE
MANUAL
PART
NO.
599910248
Better Service |
Better Reputation
Better Profit
t
ыг
~ и
SPECIFICATIONS
A. Electrical Description
Misconvergence
Less
than
0.6mm
Power
Supply
АС
120У,
60
Hz
Power
Consumption|
76
w
Picture Tube 370HYB22
13 Visual inches diagonal
90
рее
Mila
uu.
0.31
mm
Trio
dot
pitch
Dot
type
black
matrix,
Non-long
persistence
phosphor, Dark bulb, Direct etch
Input
Signal
Video
:
TTL
Level
Positive
š
:
ANALOG
0.6Ур-р/750)
Positive
Sync.
:
Separate
sync.
TTL
Level
Horizontal
sync.
Positive/Negative
Vertical
sync.
Positive/Negative
:
Composite
sync.
TTL
Level
·
Positive/Negative
ka
:
Composite
sync.
on
Green
Video
NOTE:
The
above
specifications
are
subject
to
change
(Video
0.6
Veep
ин)
without
notice
for
further
improvement.
Display
Colors
TTL
Input
:
8/16/64
colors
Analog
Input
:
Unlimited
colors
Synchronization
Horizontal
:
15.5
KHz
to
35
KHz
(Automatically)
Vertical
:
56
Hz
to
62
Hz
(Manual),
Non-
interlace
Resolution
Horizontal
:
800
dots
Vertical
:
560
lines
Video
Band
Width
30
MHz
Active
Display
Area
|
Horizontal
:
250mm
Vertical
:
180mm
Environmental
Con-|*
Operating
Temperature
0°C
то
+40°C
siderations
Humidity
30%
to
80%
Storage
Temperature
--20°C
to
+60°C
Humidity
10%
to
90%
NEC Corporation т

— щш — Ч!
А UT

B. Mechanical Description (See below diagrams)
1.
Cabinet:
Molded
plastic
cabinet
with
attachable
tilt
swivel
base.
2.
Dimensions:
368(W)
x
327.6(H)
x
382(D)
mm
3.
Weight:
15.2 kg
Side
4. Controls
Rear Controls: Power Switch
Manual Switch
Color Switch
Text color Switch
TTL/ANALOG Switch
Top Controls: Brightness Control
Contrast Control
V. Size Control
V. Position Control
V. Hold Control
H. Position Control
Text Switch
H. Width Switch
5.
Input
Signal
Terminal:
9
Pin
D-Sub
Connector
(female)
(See Page 2 for Pin Assignments)

PIN
ASSIGNMENTS
AND
SIGNAL.
LEVELS
D-SUB Type 9P
PIN
ASSIGNMENT
ОР
IBM
GRAPHICS
ADAPTER
IBM ADAPTERS
COLOR GRAPHICS
TTL 16 COLORS
SECONDARY GREEN
INTENSITY
JINTENSITY
RED
GROUND
|
NON-CONNECTION
SECONDARY
BLUE
GREEN
GROUND
HORIZONTAL
SYNC.
HORIZONTAL
SYNC.
BLUE
GROUND
VERTICAL
5УМС,
VERTICAL
5УМС.
GROUND
ENHANCED
GRAPHICS
|
PROFESSIONAL
GRAPHICS
TTL
64/16
COLORS
ANALOG
ПІ
РІМ
ASSIGNMENT
ОҒ
OTHER
COMPUTERS
т ANALOG
- | SEPARATE | COMPOSITE |- SYNC. ON
8
COLORS
[16
COLORS
|
64
COLORS
Бус
peers
EO
SECONDARY
GREEN
“ежен [o ыс
PRIMARY
PRIMARY
GREEN
BAN
H.SYNC.
|
H/V
SYNC.
|
—
|
PRIMARY
SECONDARY
INTENSITY | SECOND A
SECONDARY
BLUE GROUND
Н. SYNC./H/V SYNC.
V.SYNC.
n
|
n |
“—
”
means
GROUND
or
NON-CONNECTION
SIGNAL
LEVEL
All
signal
levels,
except
for
those
listed
below,
are
TTL.
“ж”
means
0.6
Vp-p
(VIDEO)
“б”
means
0.6
Vp-p
(VIDEO),
0.3
Vp-p
(SYNC)

TIMING CHART
SEPARATE SYNGC.
HORIZONTAL
`
жар
о
HN
VERTICAL
Q
R
5
P
be
о
5упс.
Polarity:
Positive/Negative
EXAMPLE
TIMING
REMARKS
15.75kHz|24.83kHz]|
30.1kHz
Ay
40.28
64.5
to
28.би
(15.5
to
35kHz)
:
:
TEZI
and
E/(B
+
C)
=
0.1
to
0.45
ый
150
бро
Range
1:
ЕДВ«С|-0,3
to
0.5
17.72
|
1766
16.1
to
17.8
т5
(56
to
62Hz)
13.84
|
16.11
|
166
|
12
to
17
mS
and
(O
—
R)
=0.8
to
4.0
0.066
|
Otol.mSandQ=[(O—R)—0.8]/2
+0.2|
fH
5
Horizontal x
а om H
=
wu
о
ms
Pins
Vertical
Qms
Rms
Sms
Range
1:
А
=
64.5
го
50us
*
Both
SEPARATE
SYNC.
&
COMPOSITE
SYNC.
Range
2:
А
=
50
to
37us
Range
1:
D/A
=0.7~0.75
Range
3:
А
=
37
to
28.65
Range
2:
D/A
=
0.8—0.85
R
3:
D/A
=0.75—0.8
PRESET
TIMING
ange
22kHz
|
30.5kHz
15.8kHz
|
22kHz
|30.5кН2
15.8kHz
6
£
= d
ом
[s
|»
“қа
[us
e
[зо

COMPOSITE SYNC.
HORIZONTAL
яя
واو󰾯
VERTICAL = а Да R 5
ПИ
l
Л
Л
|
ПІ
=l
Sync.
Polarity:
Positive/Negative
Equalizing Pulse is available.
Composite
Sync.
&
Video
(Sync.
on
Green)
HORIZONTAL
@ Sync. on G:
8
ч
D
ын
p
-A-(D
+
B)
+
5
—
B)
A
2
and 2 < B 545
VERTICAL
||
M-A
о
|
|
Sync.
Polarity:
Negative
TUL
Equalizing
Pulse
is
available.
EXAMPLE TIMING
[|
same
25.5КН2
|
31.5kHz
SO
TS
39.2
31.75
64.5
to
28.6и5
(15.5
to
35kHz)
3214 | 2452 | 201048 ж
=
125
|
155
|
пове
Ка
E
Ebo
0059
|
Oms
|
1635
|
16.67
16.1
to
17.8
тб
(56
to
62Hz)
эы
Ган
am
|
sm
оО
[Res
|
1347
|
15.63
12
10
17
тб
and
(О
—
R)
=
0.8
to
4.0
0.12
0
to
1.6
mS
and
Q=[(O—R)—0.8]/220.2
Horizontal
Vertical

GENERAL
MultiSync,
The
Inteligent
Monitor,
is
a
high
resolution
color
monitor
that
automatically
adjusts
to
graphics
board
scanning
frequencies
from
15.5
KHz
to
35
KHz.
MultiSync
gives
IBM
PC,
PC/XT,
and
PC/AT
users
crisp
text
and
vivid
color
graphics
displays
when
used
with
any
of
the
three
IBM
graphics
adapters
(the
CGA,
EGA
or
PGA)
MultiSync
can
also
be
used
with
other
IBM
compatible
graphics
adapters
to
provide
ІВМ
users
with
the
widest
range
of
color
monitor
compatibility
and
capability
available
in
the
market
place.
FEATURES
е
MultiSync
automatically
scans
all
frequencies
between
15.5
KHz
and
35
KHz.
@
MultiSync
is
compatible
with
the
IBM
PC,
PC/XT,
PC/AT
and
look-alikes.
®
MultiSync
is
compatible
with
the
IBM
Professional
Graphics
Adapter,
the
IBM
Enhanced
Graphics
Adapter,
the
IBM
Color
Graphics
Adapter
and
other
IBM
compatible
graphics
adapters.
ө
MultiSync's
wide
compatibility
makes
it
possible
to
upgrade
boards
or
software
without
purchasing
a
new
monitor.
@
MultiSync
has
a
maximum
horizontal
resolution
of
800
dots
and
a
maximum
vertical
resolu-
tion
of
560
lines
for
superior
clarity
of
display.
ө
MultiSync
offers
both
TTL
and
АМАГОС
signal
inputs,
and
in
the
ANALOG
mode
can
display
an
unlimited
palette
of
colors
depending
on
the
graphics
board
and
software
being
used.
ө
MultiSync
features
a
TEXT
SWITCH
with
a
choice
of
seven
colors
(red,
blue,
green,
cyan,
yellow,
white
and
magenta)
displaying
word
processing,
spread
sheets,
databases
or
other
software
in
crisp
alphanumeric
text
on
a
dark-bulb
black
background.
е
MultiSync
Раза
14
inch
diagonal
display
and
a
large,
13
inch
viewing
area.

TEXT COLOR SWITCH
POWER SWITCH @J
@ COLOR SWITCH
@ MANUAL SWITCH
TTL/ANALOG SWITCH
@PowWER SWITCH
Used
to
turn
the
power
ON
or
OFF.
When
the
power
is
ON,
the
power
indicator
is
lit.
@ MANUAL SWITCH
This
switch
selects
either
the
IBM
mode
when
OFF
or
the
manual
mode
when
ON.
When
this
switch
is
OFF,
MultiSync
automatically
works
in
the
IBM
mode
and
adjusts
itself
to
the
scanning
frequency,
resolution
and
color
requirements
of
the
IBM
compatible
graphics adapter being used.
When
this
switch
is
ON,
the
user
must
manually
select
the
number
of
colors
(8/16/64)
needed
by
the
graphics
adapter
being
used
with
the
COLOR
SWITCH
(see
No.@below).
Refer
to
instructions
accompanying
the
graphics
adapter
being
used
for
information
on
how many colors the adapter can display.

@ COLOR SWITCH
The
three
color
configurations
(8/16/64
colors)
necessary
when
using
non-IBM
compatible
graphics
adapters
can
be
set
using
No.
5
and
6
of
the
dip
switches
as
shown
below.
Refer
to
instructions
accompanying
the
graphics
adapter
being
used
for
information
on
how
many
colors the adapter can display.
P
COLOR MODE DER
No. 6
OFF
OFF
OFF
[ UNUSED | ON [ом |
a
a|
a
| NOTE
4
These
switches
should
be
set
correctly
in
relation
to
the
input
signal
of
the
graphics
adapter
!
being
used.
Refer
to
instructions
accompanying
the
graphics
adapter
бог
information
on
the input signal and refer to No. below.
@ TEXT COLOR SWITCH
Refer
to
No.@
TEXT
SWITCH
for
full
information
on
using
the
TEXT
SWITCH.
@TTL/ANALOG SWITCH
Used
to
select
an
input
video
signal
—
either
TTL
or
ANALOG
—
of
the
graphics
adapter.
It
is
important
to
determine
whether
the
input
signal
of
the
graphics
adapter
being
used
is
ANALOG
or
TTL
prior
to
connecting
the
adapter
with
your
personal
computer.
Refer
to
instructions
accompanying
the
graphics
adapter
for
information
on
the
input
signal.

!
(ӘН.
WIDTH
SWITCH
17)
TEXT
SWITCH
@ BRIGHT. CONTROL
Used
to
adjust
the
picture
brightness
of
the
screen.
О CONTRAST CONTROL
Adjusts
the
display
to
the
contrast
preferred
by
the
user.
Ө BRIGHT. CONTROL
69 V. SIZE CONTROL
(Ñ)
V.
HOLD
CONTROL
Or. POSITION CONTROL
9
У.
POSITION
CONTROL
19 CONTRAST CONTROL

6) V. SIZE CONTROL
Turn
this
knob
for
the
proper
vertical
size
of
the
display.
Turn
the
knob
clockwise
for
a
larger display; turn it counterclockwise for a smaller display.
© у. POSITION CONTROL
Turn
this
knob
for
the
proper
vertical
position
of
the
display.
Turn
the
knob
clockwise
for
a
lower
display
position;
turn
it
counterclockwise
for
a
higher
display
position.
@ v. HOLD CONTROL
Adjusts the vertical stability of the display.
Ф н. POSITION CONTROL
Turn
this
knob
for
the
proper
horizontal
position
of
the
display.
Turn
the
knob
clock-
wise
to
reposition
display
to
the
right;
turn
it
counterclockwise
to
reposition
to
the
left.
@ TEXT swiTcH
This switch controls the text mode of MultiSync.
When
it is
ON,
the
text
of
the
display
will
appear
in
one
color
selected
by
the
TEXT
COLOR
SWITCH
(No,
2,
3
and
4
of
the
dip
switch
on
the
rear
of
MultiSync),
regardless
of the colors of the software program being used.
When
it
is
OFF,
the
color
of
the
software
program
being
used
will
again
be
displayed.
The
diagram
below
of
the
dip
switches
shows
how
to
display
text
in
your
choice
of
seven
colors.
DIP SWITCH
RED
GREEN
BLUE
YELLOW
CYAN .
MAGENTA
NOTE
The text switch works only in the TTL mode.
(B H. мотн SWITCH
Adjust
this
switch
for
the
horizontal
size
of
display
preferred.
When
this
switch
is
ON,
the
width of the display size changes.
NOTE
When
the
horizontal
scanning
frequency
is
between
15
and
20
kHz,
H.
WIDTH
cannot
be
adjusted.

THE
METHOD
FOR
MOUNTING
AND
REMOVING
THE
TILT
SWIVEL
BASE
Base А
Fig. 1
1) Put the screw “а” into the round hole іп the base
“A” Ы
2) Screw the base to the display set with flat type screw
driver as per Fig. 1.
Fig. 3
Stand
the
display
correctly
so
the
JC-1401P3A
name
on
the
base
“В”
сап
be
seen
from
the
front.
(NOTE)
When
turning
the
displag
in
any
direction,
do
not
apply
any
sudden
pressure.
1.
Fig. 2
Prace the base “В” to the base “А” as рег Fig. 2. (“4p”
оп the Базе “A” and “В”.)
Turn the base “В” 180“ so that the base “В” сап not
be unfastened.
To remove the swivel base, reverse the mounting
procedure,

PART LOCATIONS
BOARD LAYOUT
B6 B7
B1
B2 B3
B4
CHASSIS FRAME
B5
BOARDS
SWITCHING REGULATOR POWER SUPPLY BOARD PWE 107
INTERFACE BOARD PWE 110
VIDEO BOARD PWE 122
CRT BOARD PWE 123
DEFLECTION BOARD PWE 105
CONTROL BOARD PWE 125A
LED BOARD PWE 125B
USER CONTROLS
POWER SWITCH
TTL/ANALOG SWITCH
MANUAL SWITCH
TEXT COLOR SWITCH

CRT SOCKET
FLYBACK TRANSFORMER
DEFLECTION BOARD PWE 105
CRT BOARD PWE 123
RIGHT 4 1
RIGHT
! B.SUB BRIGHT VR906
|
|G.
SUB
BRIGHT
VR905
|
R.SUB
BRIGHT
VR904
LEFT
G. BIAS VR902
Hs BIAS VR903
R. BIAS VR901
ғ
Cak mm Е
<_< ПО
L
WIDTH COiL L505 3
Н. LINEARITY COIL 1504 K
ADJUSTMENT CONTROLS
V. LINEARITY (2) (VR401)
V. LINEARITY (1) (VR402)
SUB. HEIGHT (1) (VR403)
SIZE PIN-CUSION (VR404)
У. BIAS (VR405)
V. MODE (VR451)
SUB. HEIGHT (2) (VR452)
SUB. H. CENTER (1) (VR501)
H. HOLD (1) (VR502)
+16V ADJUST (VR551)
F.V ADJUST (VR552)
SUB. H CENTER (2) (VR553)
SUB. H CENTER (3) (VR554)
H. HOLD (2) (VR555)
H. V. ADJUST (VR2001)
H. V. PROTECTER (1) (VR2002)
H. V. PROTECTER (2) (VR2003)
яозох= гк
А
B
С
D
E
F
G
|
J

VIDEO
BOARD
PWE
122
INTERFACE
BOARD
PWE
110
CONTROL
BOARD
PWE
125A
LED
BOARD
PWE
125B
UT SXWV
ADJUSTMENT CONTROLS
R.
SUB
CONTRAST
CONTROL
(VR701)
G.
SUB
CONTRAST
CONTROL
(VR702)
В.
SUB
CONTRAST
CONTROL
(VR703)
R.
GAIN
CONTROL
(VR704)
G. GAIN CONTROL (VR705)
B. GAIN CONTROL (VR706)
*6V
ADJUST
CONTROL
(VR707)
TTL/ANALOG
SWITCH
(SW801)
MANUAL
SWITCH
(SW802)
TEXT
COLOR/SWITCH
(SW803
NO.
2,
3,
4)
COLOR
SWITCH
(SW803
NO.
5,
6)
CONTRAST
CONTROL (VR1)
BRIGHTNESS
CONTROL
(VR2)
V.
POSITION
CONTROL
(VR3)
H.
POSITION
CONTROL
(VR5)
V. SIZE CONTROL (УВА)
V. HOLD CONTROL (VR6)
H. WIDTH SWITCH
TEXT SWITCH

SW. REG. PWB LAYOUT
+85V ADJ (VR651)
En
it HIGH VOLTAGE CONTROL
; (УВ652)
поб ШИ EET —— V. LIMITER
|-
„|
F^
a
(VR653)
&(—-
isl
T
E
|
Ұ
|

ALIGNMENT PROCEDURE
Adjustment
conditions
and
Precautions
1.
2.
Power supply voltage: AC 120V, 60 Hz
Warm up time
The
display
must
be
on
for
at
least
20
minutes
before
starting
alignments.
This
is
especially
critical
in
color
temperature
and
white
balance
adjustments.
Signals
Video: Analog 0.6 Vp-p, 750, positive
analog sync. on green
video: 0.6 Vp-p
synchronizing: 0.3 Vp-p
Synchronizing: TTL level negative/positive ə
separate/composite
Scanning
Frequency:
H
15
kHz~
35
kHz
V 60 Hz
Unless
otherwise
specified,
adjust
at
signal
6
(22
kHz).
SW. REG. UNIT
1-1. +B, (VR651) *85V LINE
Adjust VR651 to be 85 VDC
1-2. +Вн (VR652) High Voltage control
This
control
is
permanently
sealed
at
factory.
Do not attempt to readjust.
1-3.
+В,
ум
(VR653)
V.
limit
(СТ
—
Gnd
Voltage)
Remove C-connector.
Adjust VR653 to be 122 Volts.
Note:
Do
not
operate
the
SW.
Reg.
unit
itself
without
any
load.
DEF PWB Pre-Adjustment
1) VR551
+16V ADJ
2) VR552 —>
FV ADJ
DEF PWB
NEC PWE-105
3) H.V. PROT.
1 VR2002
H.V. PROT. 2 VR2003
Figure 1
— 15 —

Remove K and C connectors, and Apply 24V DC between K2 and K3.
Or just only remove C connector.
(1) +16V adjustment
Adjust TP551-GND to 16\+0.05У DC. (VR551)
(2) Receive signal 1 and adjust VR552 so that the voltage between TP552 and Gnd is 10+0.05V DC.
(3) Н.М. Protector
The high Voltage protector control 1 (VR2002) and control 2 (VR2003) are permanently
sealed at factory.
Do not attempt to readjust!
3. Video PWB pre-Adjustment
+6V ADJUST
VR707
VIDEO PWB
PWE-122
Figure 2
(1) +6V adjustment
Adjust VR707 so that the voltage between TP701 and GND is 6V+0.05V DC.
4. Main Adjustments
Unless otherwise specified, adjust the controls on the control PWB as shown below:
VR1 Contrast: Max. (fully clockwide)
VR2 Brightness: So that no background raster appears
VR3 “У. position: Center
VR4 H. position: Center
VR5 V. size: Center
VR6 V.hold: Proper position
SW2 H.size: ON
SW3 TEXT SW: OFF
Focus control: Adjust for the optimum picture.

TREE
4-1) Adiustment of H. raster centering
Turn
the
brightness
control
fully
clockwise
so
that
background
raster
can
be
seen,
then
connect
the
H
connector
in
the
position
so
that
the
background
raster
is
in
the
center
of
the
CRT
screen.
If
the
raster
is
off
to
one
side,
insert
the
5
H
соппестог
here
(adjust
to
one
side
ог
ЕЕ
<
—
the
other
by
changing
the
direction
of
the
H.
center
connector).
Insert
here
if
raster
centering
correction
is
. not needed.
Video PWB component side
Figure 3
NOTE:
Due
to
overscan,
it
is
not
possible
to
center
the
background
raster
if
the
horizontal
frequency
is
between
15
kHz
and
20
kHz.
42)
(1) H.hold
a)
Short
between
TP501
and
GND.
b)
Apply
signal
3
(30
kHz)
and
adjust
H.
hold
(1)
VR502
so
that
the
entire
picture
ap-
pears.
c)
Apply
signal
2
(20
kHz)
and
adjust
H.
hold
(2)
VR555
so
that
the
entire
picture
ap-
pears.
(2) H.V. ADJ (VR2001)
The
H.V.
ADJ
(VR2001)
is
permanently
sealed
at
factory.
Do not attempt to readjust.
(3) Н. linearity
Adjust
L504
for
the
optimum
H.
linearity.
№
at
this
time
the
picture
is
horizontally
mis-
positioned,
it
is
possible
to
adjust
VR4
to
center
it,
but
after
adjustment
of
the
linearity
set
VR4
to
the
mechanical
center.
(4)
H.
position
(adjust
to
the
center
of
the
raster)
a)
Adjust
sub
H.
center
1
VR501
to
center
the
picture
when
signal
3
(30.48
kHz)
is
applied.
b)
Adjust
sub
H.
center
3
VR554
to
center
the
picture
(1
mm
to
the
left)
when
signal
6
(22
kHz)
is
input
for
mutuality
between
actual
EGA
timing
and
test
timing.
c)
Adjust
sub
H.
center
2
VR553
to
center
the
picture
when
signal
5
(15.75
kHz)
is
applied.
d)
Check
that
the
picture
is
centered
when
the
signals
in
a),
b),
and
c)
above
are
applied.
NOTE:
Adjust
in
the
order
а)
>
b)
-
с)
(5)
Side
pincushion
Adjust
VR404
for
the
optimum
side
pincushion
distortion.
Be
careful
that
there
is
no
barrel
distortion.

(6) H. width
Adjust
H.
width
1.505
so
that
the
size
of
the
picture
when
signal
6
(22
kHz)
is
applies
is
250mm.
Perform
this
adjustment
with
the
H.
wide
switch
SW2
on.
If
the
size
cannot
be
adjusted
to
250mm
even
if
H.
width
L505
is
turned
fully,
turn
L504
slightly
to
correct
this.
V. position
Vertically
center
the
picture
when
adjustment
signal
6
(22
kHz)
is
applies
(VR3,
V.
POSI-
TION)
V. linearity
Adjust
VR401
and
VR402
so
that
vertical
linearity
is
optimum
when
signal
6
(22
kHz)
is
applies.
V. size/V. bias
a)
Adjust
sub
height
VR403
so
that
the
vertical
amplitude
is
180
mm
when
signal
3
(30.48
kHz)
is
applies
is
180
mm.
Also
adjust
V.
bias
VR405
so
that
the
voltage
between
DY4
and
GND
is
11.5V
DC.
b)
Adjust
sub
height
VR452
so
that
the
vertical
amplitude
when
signal
5
(15.75
kHz)
is
applies
is
180
mm.
c)
Adjust
V-mode
VR451
so
that
the
vertical
amplitude
is
180
mm
when
V-mode
signal
4
(30.48
kHz,
400
lines)
is
applies.
Set
the
MANUAL
switch
to
the
OFF
(PRE-SET
mode)
when
performing
this
adjust-
ment.
Also
V-mode
(Input
pin
#5)
should
be
low.
d)
Applies
the
signals
in
above
steps
a),
b),
and
c)
and
check
that
the
vertical
amplitude
for
each
is
180
тт#2
mm.
If
readjustment
is
necessary,
start
from
step
a)
and
proceed
in
order.
4-3)
Adjustment
of
video
amplitude
and
white
balance
NOTE:
Before
performing
this
adjustment,
check
that
the
video
signals
are
as
follows:
Be
sure
to
set
the
TTL/ANALOG
SW
to
ANALOG
position.
Video:
analog
0.6
Vp-p
Synchronizing: separate TTL level
Unless
otherwise
specified,
use
signal
8
for
the
adjustments.
(1) Initial setting of adjustment VR
VR701
~
703
SUB
cont.
control
Fully
clockwise
VR704
~
706
GAIN
control
Fully
counterclockwise
VR901
~
903
BIAS
control
Fully
counterclockwise
VR904
~
906
SUB
BRIGHT
control
Fully
clockwise
Video contrast adjustment
a)
Adjustment
of
gain
control
—
use
signal
7
1)
Receive
a
window
pattern
(within
a
range
for
which
ABL
does
not
function
even
with
a
maximum
contrast,
and
preferably
with
a
video
range
of
1/3
to
1/2H
x
1/2V).
ii)
Turn
the
contrast
control
fully
clockwise
and
the
brightness
control
fully
counter-
clockwise.
йі)
Adjust
VR704,
VR705,
and
VR706
so
that
R,
G,
and
B
OUT
respectively
on
the
video
PWB
become
40
Vp-p.
After
adjusting,
check
each
Vp-p,
and
if
not
proper
readjust.