Atari SM124 User manual

A
ATARI®
Chassis
No.: MT -9
SVEN
HIGH
-RESOLUTION
MONOCHROME
MONITOR
CONTENTS
SAFETY
PRECAUTIONS
2
SPECIFICATIONS
3
ADJUSTMENT AND
MAINTENANCE 3'
THEORY OF
OPERATION
5
BLOCK
DIAGRAM
8
TIMING
CHART
9
TRANSISTOR & IC
BASING 10
VOLTAGE
CHART
11
COMPONENT OF P.C.B
13
TROUBLESHOOTING
CHART
16
REPLACEMENT
PARTS
LIST
26
EXPLODED
VIEW ..
29
SCHEMATIC DIAGRAM
30
SERVICE
MANUAL
Printed in Korea
P/N
483-303A

missing page 2

SPECIFICATIONS
1. CATHODE
RAY
TUBE
Type: Non
-glare
DARK
Size &
Deflection
angle: 12", 90°
Neck
diameter: 20 mm
Phosphor: Paper
White
2. INPUT
Input signal:
TTL
Signal
•
Video :
1 Vp-p
Positive
•
Audio
: 1
Vp-p
•
Vertical Drive
: 5 ±
1.5 Vp-p
Negative
•
Horizontal
Drive : 5 ±
1.5 Vp-p
Negative
Power Input : AC
220V 50Hz, 0.26A
Input
Connector :
13 Pin
Din Connector
3.
SCANNING
Horizontal
frequency :
35.7 KHz
Horizontal
retrace
time : 6.3
uS
Vertical
frequency:
71.2
Hz
Vertical
retrace
time :
420 uS
4.
VIDEO
•
Display
Area
(HXV) : 210
mm
X 130
mm
•
Amplifier
Type :
Linear
•
Frequency
band
width :
32
MHz
•
Horizontal
resolution :
1100
lines
at
center
•
Display
character :
80 X
50
characters
5.
GEOMETRIC
DISTORTION:
2.5%
max.
6.
LINEARITY
•
Horizontal
:
10%
max.
•
Vertical :
10%
max.
7.
EXTERNAL
CONTROLS:
BRIGHTNESS,
CONTRAST,
ON/VOLUME
ADJUSTMENT AND
MAINTENANCE
CIRCUIT
PROTECTION
Circuit
protection is
provided
by one
Mini fuse,
on the
power
Pc
board. A
0.5
Ampere
fuse
(F901)
is
wired
into one
side
of
the
AC line and
provides
primary
protection
to the
entire
chassis.
1.
CENTERING
ADJUSTMENT
CAUTION: The
following
adjustment points are
close to
the
high voltage
yoke
terminal. If the
raster is
not centered
in the raster
opening, it may be
centered by
removing the cabinet
back and ad-
justing the
centering tabs on the
neck of the
tube,
located at the
rear of the deflection
yoke.
Turn
the whole
device clockwise or
counter-
clockwise.
To increase
the amount
of raster
shift,
move the two
tabs which
project from
the device,
farther apart. If
the raster is
tilted
on an angle,
it may be
straightened by
loosen-
ing the
deflection yoke
locking clamp and
rotating the
deflection yoke.
2.
FOCUS'
Adjust
the fours control (VR703)
for best overall focus of the
test pattern (marked with the
symbol "%"). Usually the center
and corners of the screen do
not focus at the same setting and
a compromise must be
made.
3.
BRIGHTNESS
Adjust
subbrightness control (VR301) for visual
cut off of the
raster when
external brightness is turned to
maximum.
4. VERTICAL
SIZE AND LINEARITY
ADJUSTMENT
The vertical size
control (VR602) should
be adjusted for the
picture to fill the screen vertically, the
linearity control
(VR603) should be adjusted for best
overall vertical lineari-
ty.
Adjustment of either control will not affect the adjustment
of the
other.
5. HORIZONTAL SIZE AND LINEARITY
ADJUSTMENT
The horizontal size control (L702) is located on
the main PCB,
it should be adjusted for
the picture to fill the screen horizon-
tally,
the linearity control
(L703) should be adjusted for the
best overall horizontal
linearity adjustment so
neither con-
trol will affect the adjustment of
the other.
- 3 -

PINCUSHION AND
BARRELLING
b
a.a': 1.5
mm
max.
b.b':
1.5 mm
max.
fa'
v
a
I
a
-a':
3.0
mm
max.
a'
a
-b:
2.0
mm
max.
d
TRAPEZOID
1
i
1
/
1
i
1
c.c':
1.5 mm max.
—
____04
d.d': 1.5 mm max.
1
1 1
1
1...
I
I
d '
4--
t
---------
b-b':
2.0
mm
max.
---------------------
PARALLELOGRAM
YORK
TILT
Active video
CRT
Fig. 2,
Geometry
Measurements
c -d: 2.0 mm
max.
T =
1°
max.
b '
—
4
—

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missing page 6

missing page 7

(
SOUND
INPUT
VERT.
SOUND
AMP.
TDA1170D
SOUND
S.P
MAIN
SYNC.
71.2Hz
VIDEO
INPUT
VERT.
OSC.
VERT.
AMP.
VERT.
OUTPUT
12V
GND
12V
GND
12V
REGULATOR
HOR.
SYNC.
35.7KHz
VIDEO
AMP.
CONTRAST
BRIGHTNESS
MONO
STABLE
CIRCUIT
VIDEO
OUTPUT
V.Dy
ASTABLE
CIRCUIT
HORIZ.
DRIVE
CRT
H.DY
HORIZ.
OUTPUT
AC
220V
50Hz
12KV
F.B.T
1
00
rs
0
CI)

H.SYNC
25pS
VIDEO
BLANK
V.SYNC
VIDEO
BLANK
1 11
35pS 0.1.--20pS
0.5pS-01
-3.5pS
-01
14.0845mS
1.50S —H
1
.41-1Lines-•-.4
(0.0281mS)
(0.9558mS)
H
34
Lines
500
Lines
(14.056mS)
(O.506mS)
(0.84338mS)
30 e l
(1.855mS)
400
Lines He— —66
(11.245mS)

TIMING
CHART
HORIZONTAL
TIMING
VIDEO
10.5uS
0.4
6uS
40uS
SYNC.
1
uS
5uS
7uS
4.5uS
15.75KHz
(63.5uS)
VERTICAL TIMING
VIDEO
1.396mS
ill
1.1134mS
12.7mS 1.41mS
0.19mS
SYNC.
0.19mS
---04 4
1.016mS
60Hz
(16.69mS)
108
*
NOTES
1. SIGNAL
INPUT LEVEL:
1Vp-p
2.
TIME TOLERANCE:
*0.1%
3. THE
MONITOR IS ADJUSTED ACCORDING TO THE ABOVE TIMINGS
AND FREQUENCY.
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