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CHASSIS
SERVICE MANUAL
SPECIFICATIONS
MCM 21T1
N3
COLOR Monitor
AEP Model
Chassis No. SCC-L04S-A


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MCM 21T1
­ 2 ­
LEAKAGE TEST
The AC leakage from any exposed metal part to earth ground
and from all exposed metal parts to any exposed metal part hav-
ing a return to chassis, must not exceed 0.5 mA (500
microampers).
Leakage current can be measured by any one of three methods.
1. A commercial leakage tester, such as the Simpson 229 or
RCA WT-540A. Follow the manufacturers' instructions to
use these instruments.
2. A battery-operated AC milliammeter. The Data Precision
245 digital multimeter is suitable for this job.
3. Measuring the voltage drop across a resistor by means of a
VOM or battery-operated AC voltmeter. The "limit" indica-
tion is 0.75 V, so analog meters must have an accurate low-
voltage scale. The Simpson 250 and Sanwa SH-63Trd are
examples of a passive VOMs that are suitable. Nearly all
battery operated digital multimeters that have a 2 V AC
range are suitable. (See Fig. A)
WARNING!!
NEVER TURN ON THE POWER IN A CONDITION IN
WHICH THE DEGAUSS COIL HAS BEEN REMOVED.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY SHADING AND MARK
¡ ON THE SCHEMATIC DIAGRAMS, EXPLODED
VIEWS AND IN THE PARTS LIST ARE CRITICAL FOR
SAFE OPERATION. REPLACE THESE COMPONENTS
WITH SONY PARTS WHOSE PART NUMBERS AP-
PEAR AS SHOWN IN THIS MANUAL OR IN SUPPLE-
MENTS PUBLISHED BY SONY. CIRCUIT ADJUST-
MENTS THAT ARE CRITICAL FOR SAFE OPERATION
ARE IDENTIFIED IN THIS MANUAL. FOLLOW THESE
PROCEDURES WHENEVER CRITICAL COMPONENTS
ARE REPLACED OR IMPROPER OPERATION IS SUS-
PECTED.
After correcting the original service problem, perform the fol-
lowing safety checks before releasing the set to the customer:
1. Check the area of your repair for unsoldered or poorly-sol-
dered connections. Check the entire board surface for solder
splashes and bridges.
2. Check the interboard wiring to ensure that no wires are
"pinched" or contact high-wattage resistors.
3. Check that all control knobs, shields, covers, ground straps,
and mounting hardware have been replaced. Be absolutely
certain that you have replaced all the insulators.
4. Look for unauthorized replacement parts, particularly tran-
sistors, that were installed during a previous repair. Point
them out to the customer and recommend their replacement.
5. Look for parts which, though functioning, show obvious
signs of deterioration. Point them out to the customer and
recommend their replacement.
6. Check the line cords for cracks and abrasion. Recommend
the replacement of any such line cord to the customer.
7. Check the B+ and HV to see if they are specified values.
Make sure your instruments are accurate; be suspicious of
your HV meter if sets always have low HV.
8. Check the antenna terminals, metal trim, "metallized"
knobs, screws, and all other exposed metal parts for AC
Leakage. Check leakage as described below.
Fig. A. Using an AC voltmeter to check AC leakage.
SAFETY CHECK-OUT
1.5 k
0.15
µF
AC
Voltmeter
(0.75 V)
To Exposed Metal
Parts on Set
Earth Ground
CAUTION ON DAS (ECS) CONNECTOR
· The connector for DAS (ECS) adjustment is provided inside
the cover shown below. Be careful with an electrical shock
when connecting the connector with the power supplied. Also,
return the removed cover to the home position.
Rear side


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MCM 21T1
­ 3 ­
POWER SAVING FUNCTION
Failre
+B failure
Horizontal / Vertical Deflection
failure, Thermal protector
ABL protector
HV failure
Aging / Self Test
Power LED
Orange
Off
(0.5 sec)
(0.5 sec)
Orange
Off
(1.5 sec)
(0.5 sec)
Orange
Off
(0.5 sec)
(1.5 sec)
Orange
Off
Orange
Off
(0.25 sec)
(0.25 sec)
(0.25 sec)
(1.25 sec)
Orange
Off
Green
Off
(0.5 sec)
(0.5 sec)
(0.5 sec)
(0.5 sec)
Aging Mode (Video Aging) : During Power Save, press "MENU" key for longer than 2 second.
Self Test (OSD Color Bar)
: During Power Save, press "CONTRAST" + (
/) key for longer than 2 second.
Reliability Check Mode
: During Power Save, press "CONTRAST" ­ (
?) key for longer than 2 second.
DIAGNOSIS
This monitor meets the power-saving guidelines set by VESA and
Energy Star, as well as the more stringent NUTEK .
If the monitor is connected to a computer or video graphics board
that is VESA DPMS (Display Power Management Signaling)
compliant, the monitor will automatically reduce power con-
sumption in three stages as shown below.
You can set the delay time before the monitor enters the power
saving mode using the OSD. Set the time according to "Setting
the power saving delay time".
Note
If no video signal is input to the monitor, the "NO INPUT SIG-
NAL" message appears. After the delay time has passed, the
power saving function automatically puts the monitor into the ac-
tive-off mode and the indicator lights up orange. Once the hori-
zontal and vertical sync signals are detected, the monitor auto-
matically resumes its normal operation mode.
1
2
3
4
5
Power consumption
mode
Normal operation
Standby (1st mode)
Suspend (2nd mode)
Active-off (3rd mode)
Power-off
Power
consumption
160 W
100 W
15 W
5 W
0 W
Horizontal
sync signal
present
absent
present
absent
--
Vertical
sync signal
present
present
absent
absent
--
Screen
active
blank
blank
blank
--
u indicator
Green
Green and orange
alternate
Green and orange
alternate
Orange
Off
Recovery time
--
Approx. 3 sec.
Approx. 3 sec.
Approx. 10 sec.
--


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MCM 21T1
­ 4 ­
TIMING SPECIFICATION
MODE AT PRODUCTION
MODE 1
MODE 2
MODE 3
MODE FOR CUSTOMER
VGA
E-VGA
VGA
VESA
VESA
SNI-100Hz
VESA
VESA
SNI-100Hz
MGA
RESOLUTION
720 X 400
720 X 400
640 X 480
640 X 480
640 X 480
640 X 480
800 X 600
800 X 600
800 X 600
800 X 600
CLOCK
28.325 MHz
36.082 MHz
25.175 MHz
31.500 MHz
36.000 MHz
40.500 MHz
49.500 MHz
56.250 MHz
67.500 MHz
81.000 MHz
-- HORIZONTAL --
H-FREQ
31.472 kHz
37.822 kHz
31.469 kHz
37.5 kHz
43.269 kHz
50.625 kHz
46.875 kHz
53.674 kHz
63.92 kHz
76.705 kHz
usec
usec
usec
usec
usec
usec
usec
usec
usec
usec
H. TOTAL
31.774
26.44
31.778
26.667
23.111
19.753
21.333
18.631
15.644
13.037
H. BLK
6.355
6.485
6.356
6.349
5.333
3.951
5.172
4.409
3.793
3.16
H. FP
0.635
0.748
0.636
0.508
1.556
0.395
0.323
0.569
0.474
0.395
H. SYNC
3.813
1.247
3.813
2.032
1.556
1.58
1.616
1.138
0.948
1.185
H. BP
1.906
4.49
1.907
3.81
2.222
1.975
3.232
2.702
2.37
1.58
H. ACTIV
25.419
19.955
25.422
20.317
17.778
15.802
16.162
14.222
11.852
9.877
-- VERTICAL --
V. FREQ(HZ)
70.094 Hz
84.236 Hz
59.94 Hz
75 Hz
85.008 Hz
100.049 Hz
75 Hz
85.061 Hz
100.032 Hz
120.038 Hz
lines
lines
lines
lines
lines
lines
lines
lines
lines
lines
V. TOTAL
449
449
525
500
509
506
625
631
639
639
V. BLK
49
49
45
20
29
26
25
31
39
39
V. FP
13
9
10
1
1
1
1
1
1
2
V. SYNC
2
3
2
3
3
3
3
3
3
3
V. BP
34
37
33
16
25
22
21
27
35
34
V. ACTIV
400
400
480
480
480
480
600
600
600
600
-- SYNC --
INT(G)
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
EXT(H/V)/POLARITY
YES N/P
YES N/P
YES N/N
YES N/N
YES N/N
YES N/N
YES P/P
YES P/P
YES P/P
YES N/N
EXT(CS) /POLARITY
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
INT/NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
SIZE(21")
388x291 mm
388x291 mm 388x291 mm
388x291 mm 388x291 mm
388x291 mm 388x291 mm
388x291 mm 388x291 mm
388x291 mm
MODE AT PRODUCTION
MODE 4
MODE 5
MODE 6
MODE 7
MODE 8
MODE 9
MODE FOR CUSTOMER
VESA
SNI-100Hz
MGA
VESA
SNI-110Hz
VESA
VESA
SNI-100Hz
VESA
VESA
RESOLUTION
1024 X 768
1024 X 768
1024 X 768
1152 X 864
1152 X 864
1280 X 1024
1280 X 1024
1280 X 1024
1600 X 1200
1600 X 1200
CLOCK
94.5 MHz
111.2 MHz
131 MHz
108 MHz
157 MHz
135 MHz
157.5 MHz
184.9 MHz
202.5 MHz
229.5 MHz
-- HORIZONTAL --
H-FREQ
68.677 kHz
80.814 kHz
97.47 kHz
67.5 kHz
100.128 kHz
79.976 kHz
91.146 kHz
107 kHz
93.75 kHz
106.25 kHz
usec
usec
usec
usec
usec
usec
usec
usec
usec
usec
H. TOTAL
14.561
12.374
10.26
14.815
9.987
12.504
10.971
9.346
10.667
9.412
H. BLK
3.725
3.165
2.443
4.148
2.65
3.022
2.844
2.423
2.765
2.44
H. FP
0.508
0.288
0.244
0.593
0.204
0.119
0.406
0.173
0.316
0.279
H. SYNC
1.016
1.151
0.977
1.185
0.815
1.067
1.016
0.692
0.948
0.837
H. BP
2.201
1.727
1.221
2.37
1.631
1.837
1.422
1.558
1.501
1.325
H. ACTIV
10.836
9.209
7.817
10.667
7.338
9.481
8.127
6.923
7.901
6.972
-- VERTICAL --
V. FREQ(HZ)
84.997 Hz
99.894 Hz
120.334 Hz
75 Hz
110.03 Hz
75.025 Hz
85.024 Hz
99.91 Hz
75 Hz
85 Hz
lines
lines
lines
lines
lines
lines
lines
lines
lines
lines
V. TOTAL
808
809
810
900
910
1066
1072
1071
1250
1250
V. BLK
40
41
42
36
46
42
48
47
50
50
V. FP
12
21
21
1
2
11
V. SYNC
3
3
3
3
3
3
3
3
3
3
V. BP
36
36
37
32
41
38
44
42
46
46
V. ACTIV
768
768
768
864
864
1024
1024
1024
1200
1200
-- SYNC --
INT(G)
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
EXT(H/V)/POLARITY
YES P/P
YES N/N
YES N/N
YES P/P
YES N/N
YES P/P
YES P/P
YES P/P
YES P/P
YES P/P
EXT(CS) /POLARITY
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
INT/NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
NON INT
SIZE(21")
388X291 mm 388X291 mm 388X291 mm 388X291 mm 388X291 mm 364X291 mm 364X291 mm 364X291 mm 388X291 mm 388X291 mm
'98.06.05 Ver.


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MCM 21T1
­ 5 ­
Note: Hand degauss must be used on stand-by or power-off condition.
This model has an automatic earth magnetism correction function by using an earth
magnetism sensor and a LCC coil. When using a hand degauss while monitor (LCC
coil) is being operated, it sometimes gets magnetized, and the system may not work
properly as a result.
TABLE OF CONTENTS
Section
Title
Page
1. GENERAL ................................................................. 1-1
2. DISASSEMBLY
2-1.
Cabinet Removal ............................................... 2-1
2-2.
D Board Removal .............................................. 2-1
2-3.
G Board Removal .............................................. 2-2
2-4.
A Board Removal .............................................. 2-2
2-5.
L Board Removal .............................................. 2-3
2-6.
I/O TERMINAL Board Assy Removal ............. 2-3
2-7.
Service Position .................................................. 2-4
2-8.
H and J Boards Removal ................................... 2-4
2-9.
Picture Tube Removal ....................................... 2-5
3. SAFETY RELATED ADJUSTMENT ............. 3-1
4. ADJUSTMENTS ..................................................... 4-1
5. DIAGRAMS
5-1.
Block Diagrams .................................................. 5-1
5-2.
Frame Shcematic Diagram ................................. 5-7
5-3.
Circuit Boards Location ..................................... 5-9
5-4.
Schematic Diagrams and Printed Wiring
Boards ................................................................. 5-9
(1)
Schematic Diagram of D Board ........................ 5-13
(2)
Schematic Diagrams of G, GA, H, J and
L Boards ............................................................ 5-17
(3)
Schematic Diagram of A Board ........................ 5-24
5-5.
Semiconductors ................................................. 5-29
6. EXPLODED VIEWS
6-1.
Chassis ............................................................... 6-1
6-2.
Picture Tube ...................................................... 6-2
6-3.
Packing Materials ............................................... 6-3
7. ELECTRICAL PARTS LIST ............................ 7-1