CTX CMS-3435 User manual

| | |
RD
|
NO.
SM-0030
|
CHUNTEX
:
|
:
; | |
SERVICE MANUAL | CMS-3435/36
CAUTION:
Before
servicing
this
chassis,
it
is
important
that
the
service
technician
should
read
the
"Safety
Precautions"
and
"Product
Safety
Notice"
in
this
Service
Manual.
CONTENTS
SAFETY
PRECAUTIONG...........:::ccceeereeeteeeeees
2
DESCRIPTION
OF
CIRCUIT........0.::
cece
10
CHECK
OF
HIGH
VOLTAGE
HOLD
DOWN
ADJUSTMENTS.
...0...
cece
ecceeseeeeeeseeeeeneeeenenetes
13
CIRCUIT..........::eccsccssessrrscesnseseesesereceseeceneesensseenns
3
TROUBLE
SHOOTING...
16
PRODUCT
SAFETY
NOTICE............::ceeeeeereees
3
BASIC
CIRCUIT
DIAGRAM.............::eeeeereereee
22
FEATUREG............-cccesssssssesseseeessesnesseerereetensenenss
4
PRINTED
WIRING
BOARD...........:::csereteereees
25
SPECIFICATIONS.
.........csecccseesseseeeeeteeeeeeersenseens
5
BLOCK
DIAGRAM.
...........2.:ccceeseeseeeeeeteeeetee
eee
eetes
27
CONTROLG.......-..0.csssssssseecseseessreeneersteeesseenseneese
6
EXPLODED
VIEW
DIAGRAM.............:-
eee
28
SIGNAL
TIMING
CHART.
..........::ceeeeeeeseereeeees
8
REPLACEMENT
PARTS
LIST............-::eeeere
29
SPECIFICATIONS
AND
PARTS
ARE
SUBJECT
TO
CHANGE
FOR
IMPROVEMENT
HIGH
RESOLUTION
MULTISCAN
COLOR
MONITOR
March
1990.
EDITION
1.0

SAFETY
PRECAUTIONS
NOTICE:
Comply
with
all
cautions
and
safety
related
notes
located
on
or
inside
the
cabinet
and
on
the
chassis
or
picture
tube.
The
following
precautions
should
be
observed.
1.
Do
not
install,
remove,
or
handle
the
picture
tube
in
any
manner
unless
shatterproof
goggles
are
worn.
People
not
so
equipped
should
be
kept
away
while
picture
tubes
are
handled.
Keep
picture
tube
away
from
the
body
while
handling.
When
replacing
a
chassis
in
the
monitor,
all
the
protective
devices
must
be
put
back
in
place,
suchas
barriers,
non-metallic
knobs,
adjustment
and
compartment
shields,
and
isolation
resistor-
capacitor,
etc.
When
service
is
required,
observe
the
original
lead
dress.
Extra
precaution
should
be
taken
to
assure
Correct
lead
dress
in
the
high
voltage
circuitry
area.
Always
use
the
manufacturer’s
replacement
components.
Especially
critical
components
as
indicated
on
the
Replacement
parts
list
should
not
be
replaced
by
other
manufacturer’s.
Fur-
thermore
where
a
short
circuit
has
occurred,
replace
those
components
that
indicate
evidence
of
overheating.
Before
returning
a
serviced
monitor
to
the
cus-
tomer,
the
service
technician
must
throughly
test
the
unit
to
be
certain
that
it
is
completely
safe
to
operate
without
danger
of
electrical
shock,
and
be
sure
that
no
protective
device
built
into
the
monitor
by
the
manufacturer
has
become
defec-
tive,
or
inadvertently
defeated
during
servicing.
Therefore,
the
following
checks
should
be
per-
formed
for
continued
protection
of
the
customer
and
service
technician.
High Voltage
This
monitor
is
provided
with
a
high
voltage
hold
down
circuit
for
clearly
indicating
that
voltage
has
increased
in
excess
of
a
predetermined
value.
Comply
with
all
notes
described
in
this
Service
Manual
regarding
this
hold
down
circuit
when
servicing,
so
that
this
hold
down
circuit
may
function
correctly.
Service Warning
With
minimum
Brightness
and
Contrast
the
operating
high
voltage
in
this
display
is
lower
than
25KV.
If
any
component
having
influence
on
the
high
voltage
is
replaced,
confirm
that
the
high
voltage
with
minimum
Brightness
and
Contrast
is
lower
than
25
KV.
To
measure
high
voltage
use
a
high
impedance
high-voltage
meter.(SENSITIVE
RE-
SEARCH
Model:
ESH
or
Equivalent)
Connect
(-)
to
chassis
earth
and
(+)
to
the
CRT
anode
button.
(See
the
following
connection
diagram
Fig.
1.)
NOTE:
1)
Turn
power
switch
off
without
fail
before
making
the
connection
to
the
Anode
button.
2)
Beforeturn
power
switch
ON,
confirm
the
AC
line
voltage,
set
the
"Voltage
Selector".
CRT ANODE
HIGH IMPEDANCE
H.V.METER
SENSITIVE RESEARCH
Model:ESH
or
equivalent.
CHASSIS
GROUND
Fig. 1
X-radiation
TUBE:
The
primary
source
of
X-radiation
in
this
monitor
is
the
picture
tube.
The
tube
utilized
in
this
chassis
is
specially
constructed
to
limit
X-
radiation
emissions.
For
continued
X-radiation
protection,
the
replacement
tube
must
be
the
Same
type
as
the
original,
manufacturer
ap-
proved
type.
When
troubleshooting
and
making
test
measurements
in
a
monitor
with
a
problem
of
excessive
high
voltage,
avoid
being
unneces-
sarily
close
to
the
picture
tube
and
the
high
voltage
components.
Do
not
operate
the
chas-
sis
longer
than
is
necessary
to
locate
the
cause
of excessive voltage.

CHECK
OF
HIGH
VOLTAGE
HOLD
DOWN
CIRCUIT
Checking
of
the
high
Voltage
hold
down
circuit
operation.
1. Turn the switch of the unit OFF.
2. Set Brightness, Contrast controls to max.
3.
Connect
a
DC
Voltmeter
and
an
adjustment
jig
as
shown
in
Fig.
2.
4.
Setthe
adjustment
VR
to
fully
counterclockwise.
5.
Turn
the
switch
of
the
unit
ON
and
gradually
rotate
the
adjustment
VR
counterclockwise.
6.
Check
that
a
reading
of
DC
voltmeter
is
less
than
9.4V
+
0.5V
when
picture
disappears.
Clockwise i
Variable
resistor © TPS
To chassis
ground
VR309
500K-B H. V.
1/2
W
Protector
R391 i R390
Main Board Assembly
Fig. 2
7. Turnthe switch of the unit OFF immediately after
checking that the picture disappears.
8. Remove the adjusting jig and the DC voltmeter.
Note: Reading of 9.4V is approximately equivalent
to 28 KV of CRT Anode High Voltage.
PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in the color
monitor units have special safety related charac-
teristics.
These 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 this Service Manual.
Electrical components having such features are iden-
tified by marking with "!" on the parts list in this Service
Manual.
The use of a substitute replacement component
which does not have the same safety characteristics
as the manufacturer recommended replacement
one, shown in the parts list in this Service Manual,
may create shock, fire, X-radiation, or other hazards.
Product Safety is continuously under review and new
instructions are issued from time to time. For the
latest information, always consult this Service
Manual.

FEATURES
OF
CMS-3435/36
Multiscan,
model
CMS-3435/36,
from
Chuntex
is
a
high
resolution
color
monitor
that
automatically
ad-
justs
to
graphics
board
scanning
frequencies
from
15.5KHz
to
38KHz.
Multiscan
gives
IBM
PC,
PC/
XT,
PC
/
AT,
PS
/
2
and
PC
compatibles
users
crisp
text
and
vivid
color
graphics
displays
when
used
with
any
of
the
IBM
graphics
adapters
(the
CGA,
EGA,
MCGA,
VGA,
or
3514A).
Multiscan
can
also
be
used
with
other
IBM
compatible
graphics
adapters
to
provide
IBM
users
with
the
widest
range
of
color
monitor
compatibility
and
capability
available
in
the
market
place.
e
CMS-3435/36
automatically
scans
all
frequen-
cies
between
15.5KHz
and
38KHz
and
is
com-
patible
with
the
IBM
PC,
PC
/
XT,
PC
/
AT,
PS
/2
and
look-alikes.
e
CMS-3435/36
uses
14
inch
fine
pitch
(0.29mm
or
0.28mm)
non-glare
CRT
and
has
a
maximum
horizontal
resolution
of
1024
dots
and
a
maxi-
mum
vertical
resolution
of
768
lines
for
superior
clarity
of
display.
e
CMS-3435/36
is
compatible
with
IBM
CGA,
EGA,
MCGA,
VGA,
8514A
graphic
adapters
and
non-
IBM
Boards
supporting
extended
display
modes
such
as
800
x
600,
132
columns
etc.
This
wide
compatibility
makes
it
possible
to
upgrade
boards
and
software
without
purchasing
a
new
monitor.
@
CMS-3435/36
offers
both
TTL
and
ANALOG
sig-
nal
inputs,
and
in
the
ANALOG
mode
can
display
an
unlimited
palette
of
colors
depending
on
the
graphics
board
and
software
being
used.
Fea-
tures
a
TEXT
SWITCH
witha
choice
of
four
colors
(red,
blue,
green,
amber)
displaying
word
processing,
spread
sheets,
data-bases
or
other
software
in
crisp
alphanumeric
text
on
a
dark-
bulb
black
background.
e
CMS-3435/36
is
equipped
with
vertical
auto
sizing
circuit.
The
circuit
works
according
to
horizontal
frequency
and
sync
polarization
of
IBM
CGA,
EGA
and
VGA
convention.
This
func-
tion
can
be
made
inactive
by
turning
off
the
Auto
Switch
located
on
front
panel
if
the
input
signal
is
non-IBM
standard.
PIN ASSIGNMENT
Glarorors
O\cooo/9
For TTL Input Signals
Pin
CGA
EGA
No.
16
colors
16
/
64
colors
1
Ground
Ground
2
Ground
Secondary
Red
3
Red
Primary
Red
4
Green
Primary
Green
5
Blue
Primary
Blue
6
Intensity
Secondary
Green
7
N.
C.
Secondary
Blue
8
H.
Sync.
H.
Sync.
9
V.
Sync.
V.
Sync.
For Analog Input Signals
D-SUB
VGA
D-SUB
9 Pin 15 Pin
1 Red 1
6 R Return 6
2 Green 2
7 G Return 7
3 Blue 3
8 - B Return 8
4 H. Sync. 13
5 V. Sync. 14
9 Ground 10
9 Ground 11
9 Ground 4
*
For
VGA
cards,
signals
are
fed
into
the
monitor
via
an
anolog
cable
which
has
9
Pin
D-SUB
connector
on
one
end
and
15
Pin
D-SUB
con-
nector
on
the
other,
and
wired
as
the
table
listed
above.

SPECIFICATION
Multiscan Monitor
Picture Tube
Pitch
Input Signal
Display Colors
Synchronization
Resolution
Video Band Width
Active Display Area
Misconvergence
Power Supply
Power Comsumption
Dimensions
Weight
Environmental
Considerations
0.29mm 0.28mm
CMS-3435 CMS-3436
13 visual diagonal inches
Dark bulb, Nonglare etching
Medium short persistance
————_—.__—__{
Video: TTL Level Positive
Analog 0.7Vp-p / 75 Ohm Positive
Sync.: Separate Sync. TTL Level
Horizontal sync. Positive / Negative
Vertical Sync. _ Positive / Negative
Composite Sync. TTL Level
Polarity Positive / Negative
Composite Sync. on Green Video
Sync. 0.3Vp-p Negative (Video 0.7Vp-p Positive)
Analog
Input:
Unlimited
colors
TTL:
8/16/64
color
Horizontal: 15.5KHz to 38KHz (Automatically)
Vertical: | 50 Hz to 90 Hz (Automatically)
Horizontal: 1024 dots Vertical: 768 lines
40MHz
(Active display area is changed by signal timing)
Preset* VGA 1024x768 EGA CGA
Horizontal: 245mm 250mm 250mm 240mm
Vertical:
185mm
187mm
190mm
180mm
*Refer To Preset Timing Chart
Less than 0.4mm
AC 120V / 60Hz or 220 / 50Hz by internal setting
75W
368(W) x 378(H) x 387(D)mm
12.8kgs
Operating Temperature o°c to 40°C
Humidity 20% to 80%
Storage Temperature -20°C to 60°C
Humidity 10% to 90%

CONTROL
il
uv fF ww NW
Power Indicator
When the power is ON, the LED is lit.
Power Switch
Used to push the power ON or OFF.
Auto Switch
When this switch is on, the VASC (vertical auto-
sizing circuit) will be activated to maintain same
picture height when changing among 350 / 400
/ 480 lines different vertical resolutions according
to the sync polarization of BM VGA convention.
For some compatible VGA boards which require
to set dip switch to support different type of mo-
nitors, their sync polarization might not be com-
patible with IBM standard if they are set to sup-
port multiscan monitor instead of standard VGA
monitor while running VGA program. In such
case, this switch should be off to make the VASC
inactive without misadjusting picture height ac-
cording to wrong polarization.
Bright Control
Used to adjust the picture brightness of the
screen.
Contrast Control
Adjusts the display to the contrast preferred by
the user.
Analog / TTL Indicator
When set in TTL mode, the LED is lit.
10.
11.
Before
connecting
MULTISCAN
series
monitor
with
IBM
personal
computers
or
compatibles
and
IBM
graphics
adapters,
take
time
to
familiarize
yourself
with
the
switches
and
controls
that
give
MULTISCAN
series
monitor
all
its
compabilities.
Manual / Auto Indicator
When set in manual mode, the LED is lit.
. TTL/ Analog Switch
Used to select an input video signal - either TTL
or ANALOG - of the graphics adapter. It is impor-
tant to determine whether the input signal of the
graphics adapter being used is ANALOG or TTL
prior to connecting the adapter with your perso-
nal computer. Refer to instructions accompany-
ing the graphics adapter for information on the
input signal.
H. Center Control
Turn this knob for the proper horizontal position
of the display. Turn the knob clockwise to repo-
sition display to the right; turn it counterclock-
wise to reposition to the left.
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.
V. Center Control
Turn this knob for the proper vertical position of
the display. Turn the knob clockwise for a higher
display position; turn it counterclockwise for a
lower display position.

ON AUTO ON
12
eo OFF MANUAL OFF
COLOR TEXT H-WIDTH ||
15.
12. H. Width
13.
Switch 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.
Manual Switch
This switch selects either the IBM mode or the
manual mode. When this switch is set in Auto
mode, Multiscan automatically works in the IBM
mode and adjusts itself to the scanning frequen-
cy, resolution and color requirements of the IBM
compatible graphics adapter being used. When
this switch is set in manual mode, the user must
manually select the number of colors (8 / 16 / 64)
needed by the graphics adapter being used with
the Color Switch (see 15. below). Refer to ins-
tructions accompanying the graphics adapter
being used for information on how many colors
the adapter can display.
ud
14.
14.
15.
13. 12.
Text Switch
This switch controls the text mode of Multiscan.
When it is ON, the text of the display will appear
in one color selected by the Color Switch,
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 dis-
played. The diagram below of the dip switches
shows how to display text in your choice of four
colors. When multiscan is used with mono-
chrome cards (MDA or Hercules), please set the
Text Switch on and select one of the four colors
with the color switch (see 15 below).
Color Switch
This switch operates under following mode:
TEXT SW. OFF ON
SW.1 | SW.2 COLOR MONO
OFF ON 8 AMBER
| ON | OFF | 16 RED
| ON | OFF | 64 GREEN
OFF | OFF 64 WHITE

SIGNAL TIMING CHART
Separate Sync.
HORIZONTAL
-
VERTICAL
fo
wenn]
VIDEO
Cc
D
E
|_@
|
i
Ele
~
=
A
=
O
|
|
Sync. Polarity: Positive / Negative
Composite Sync.
Composite Sync. TTL Level
HORIZONTAL VERTICAL
l ~~VIDEO ~
2
ae
eee
el
aie
pane
ss
ee
B fe
5 a TANIA
Sync. Polarity: Positive / Negative
Equalizing Pulse is available
Composite Sync. On Green Video
HORIZONTAL ~ VERTICAL
ie oe eee |B. | ee
|
# Synd. on G: TAR UUILALAN
A —(D+B)+(5-B)
Syne. Polarity: Negative
Equalizing Puise is available
2
and 2 <= B <5uS

Display format
Horizontal Dots
Vertical Lines
Horizontal Frequency
1) Sync. Polarity
Aus
Cus
Dus
Eus
Vertical Frequency
Sync. Polarity
Oms
Pms
Q ms
Rms
Sms
PRESET TIMING CHART
EGA
8514A
31.5kHz 15.8kHz 21.8kHz 35.5kHz
31.78 31.78 31.78
1.91
25.42
0.64
70H2
14.27
0.06
1.91
11.12
1.18
25.42
0.64
70H2
14.27
0.06
1.11
12.71
0.38
25.42
0.64
60Hz
16.68
0.06
1.05
16.25
0.32
f
63
4.2
7.2
45
6.6
60Hz
16.4
0.075
1.525
12.6
2.2
45.5
4.9
1.6
39
0
60Hz
16.68
0.6
0.08
28.10
1.15
3.91
22.80
0.24
2) 87Hz
+/—
11.50
0.11
0.56
10.80
0.02
1) When AUTO SWITCH is on, the vertical auto-sizing circuit will be active according to sync.
polarity in VGA mode.
2) 8514A uses interlace mode.