Samsung MZ467 User manual

c8 SAMSUNG
SERVICE MANUAL
MDA
MONO MONITOR
CGA
MZ467 *

CONTENTS
• SPECIFICATIONS ....................................................................... 2
• SIGNAL TIMING CHART .................................................................. 3
• IMPORTANT SERVICE SAFETY PRECAUTIONS .......................................... 4 -5
• THEORY OF OPERATION ............................................................ 6 - 7
• ALIGNMENT INSTRUCTIONS ......................................................... 8 - 9
• DISASSEMBLY INSTRUCTIONS ........................................................... 10
• EXPLODED VIEW ................................................................... 11 - 12
• EXPLODED VIEW PARTS LIST ......................................................... 13 -14
• WIRING DIAGRAM AND PARTS LOCATION .............................................. 15 -16
• BLOCK DIAGRAM ....................................................................... 17
• TROUBLE SHOOTING GUIDE ......................................................... 18 - 20
• SCHEMATIC DIAGRAM ............................................................... 21 - 22
• PRINTED CIRCUIT BOARD ........................................................... 23 - 24
• WAVEFORMS (CGA) ................................................................. 25 - 26
• WAVEFORMS(MDA) ................................................................. 27 - 28
• PINVOLTAGEOFIC ..................................................................... 29
• REPLACEMENT PARTS LIST .......................................................... 30 - 38
• SEMICONDUCTOR LEAD IDENTIFICATION ................................................. 39

SPECIFICATIONS
DESCRIPTION NOMINAL LIMIT
1. Power input AC108-132V, 60Hz
OPTION
AC220V 50Hz, AC240V 50Hz
2. Power consumption
40 Watts Max 50 Watts
Video input signal Separate TTL signal 3.5Vp-p
±1.0V
Video bandwidth 25MHz at-3db
Video display size 230mm x 170mm
±3mm
3. Number of characters 2000 characters
80 Columns x 25 Rows
4. Resolution 720 dots 350 line (MDA)
640 dots 200 line (eGA)
5. CRT 14" 90 Degress deflection
WHITE, GREEN, AMBER,
PHOSPHOR/NON-GRARE
6. Synchronous
a) Horizontal 18.432KHz/15.75KHz
b) Vertical 50Hz/60Hz
7. Dimensions (W)12.4"(320 mm)
(D)12.8"(326 mm)
(H) 12.1 "(308.5 mm)
8. Weight
131bs (8.3Kg)
9. Length of signal cable 5ft (1500 mm)
10.Length of power cord 7.5ft (2300 mm)
Note: Nominal specs represent the design specs; all units should be able to approximate these -some will ex-
ceed and some may drop slightly belowthese specs.
Limit specs represent the absolute worst condition which still might be considered acceptable; in no
case should a units perform to less than within any limit specs.
2

** HORIZONTAL **
(MDA/CGA)
** VERTICAL **
MDA(V-SYNC)
CGA(V-SYNC)
MDA
CGA
MDA
CGA
SIGNAL TIMING CHART
A
-------'n'---_~o>n~- E
G H
<---7
~
~
~
I
U
J-~LF
I I I I
n n
F
A (uS) B (uS) C (uS) D (uS) E (uS)
54.3 0.6
1.1 44.3 8.3
63.5 6.6 7.2 45.2 4.5
F (mS) G (mS) H (mS) I (mS) J (mS)
20.07 0.0 0.217 18.985 0.868
16.67 1.58 2.15 12.75 0.19
3

IMPORTANT SERVICE SAFETY PRECAUTIONS
Service work should be performed only by qualified service technicians who are thoroughly familiar with all of
the following safety checks and servicing guidelines:
WARNING
1. For continued safety, do not attempt to modify
the circuit.
2. Disconnect the AC power before servicing.
3. Semiconductor heat sinks are potential shock
hazards when the chassis is operating.
SERVICING THE HIGH VOLTAGE SYSTEM AND
PICTURE TUBE
When servicing the high voltage system, remove
the static charge by connecting a 10kohm resis-
tor in series with an insulated wire (such as a
test probe) between the chassis and the anode
lead. (The AC line cord should be disconnected
from the AC outlet.)
1. The picture tube in this display monitor employs
integral implosion protection.
2. Replace with a tube of the same type and
number for continued safety.
3. Do not lift the picture tube by the neck.
4. Handle the picture tube only when wearing shat-
ter proof goggles and after discharging the high
voltage anode completely.
X-RADIATION AND HIGH VOLTAGE LIMITS
1. Be sure all service personnel are aware of the
procedures and instructions covering X-radia-
tion. The only potential' source of X-ray in a
current solidstate display monitor is the tube.
However,the picture tube does not emit
measurable X-ray radiation if the high voltage is
as specified in the "high voltage check" instruc-
tion.
It is only when high voltage is excessive that
X-radiation is capable of penetrating the shell of
4
the picture tube, including the lead in glass
material. The important precaution is to keep
the high voltage below the maximum level
specified.
2. It is essential that servicemen have available at
all times an accurate high voltage meter. The
calibration of this meter should be checked
periodically.
3. High voltage should always be kept at the rated
value-no higher. Operation at high voltages may
cause a failure of the picture tube or high voltage
circuitry and,also under certain conditions,may
produce radiation in excess of desirable levels.
4. When the high voltage regulator is operating
properly there is no possibility of an X-radiation
problem.
Everytime a color chassis is serviced,the bright-
ness should be tested while monitoring the high
voltage with a meter to be certain that the high
voltage does not exceed the specified value and
that it is regulating correctly.
5. Do not use a picture tube other than that
specified or make unrecommended circuit
modifications to the high voltage circuitry.
6. When trobleshooting or taking test measure-
ments on a display monitor'with excessively high
voltage, avoid being unnecessarily close to the
display monitor. Do not operate the display
monitor longer than is necessary to locate the
cause of excessive Voltage.
BEFORE RETURNING THE DISPLAY MONITOR
Fire and Shock Hazard
Before returning the display monitor to the
user,perform the following safety checks:
1. Inspect all lead dress to make certain that the
leads are not pinched or that the leads are not

lodged between the chassis and other metal
parts in the display monitor.
2. Inspect all protective devices such as non-
metallic control knobs, insulating materials,
cabinet backs, adjustment
and compartment
covers or shields,isolation resistor-capacitor net-
works,mechanical insulators,etc.
3. To be sure that no shock hazard exists,check
for leakage current
in the following manner:
• Plug the AC line cord directly into a 120volt AC
outlet. (Do not use an isolation transformer for
this test)
• Using two clips leads,connect 1.5 kohm, 10 watt
resistor paralleled by a 1.5uF capacitor
in series
with
all exposed metal cabinet parts and a known
earth ground such as electrical conduit or
electrical ground connected
to earth ground.
• Use a SSVM or YOM with 1000 ohms per-volt
or higher sensitivity to measure the
AC voltage
drop across the resistor.
(See Figure 1.)
• Connect the resistor to all exposed metal parts
having a return path
to the chassis(metal cabinet,
screw
heads, knobs and shafts,escutcheon,etc.)
and measure the AC voltage drop across the
resistor.
• Any reading of 0.3volt RMS (this corresponds to
0.5milliamp.AC) or more is excessive and
indicates a potential shock hazard which must
be corrected before returning the display monitor
to the
user.
SAFETY NOTICE
Many electrical and mechanical parts which have
special characteristics in this chassis often pass
unnoticed and the protection afforded by them
can not necessarily be obtained by using
re-
placement components rated for higher volt-
age,wattage,etc.
Replacement parts that
have these special safety
characteristics- are identified
in this manual,and
its supplement; electrical components having
such features are identified by a !
in the Parts
List and Schematic Diagrams.
Before replacing any of these components,read
the Parts List
in this manual carefully. The use
of substitute replacement parts that do not have
the same safety characteristics as specified in
the Parts List may create shock, fire, or other
hazards.
5
AC
VCLllETER
1500 n
TO EXPOSED
~AL PARTS
TO KNlWEN
EARTH GROlNJ

THEORY OF OPERATION
GENERAL
This monitor is a high resolution monochrome
monitor using a
AMBER,GREEN,WHITE phosphored
CRT with etched faceplate.
It receives one VIDEO signal and INTENSITY signal,
separated sync signals by TTL level.
In case of CGA MODE, It receives R,G,B, INTENSITY
and separated sync signals by TTL level.
It can operate in all of the MDA and CGA mode.
DESCRIPTION
1. Main board
1-1) Power supply
This
is a linear power supply using power
trans
(T701) and a monolithic intergrated
circuit voltage regulation
(IC701: L123CB or
LM723).
The output voltage regulation is achieved
by means of the error amplifier contained
in IC701.
The output voltage of this power supply is
fed back into the pin4 of IC701.
This voltage is compared to the reference
voltage internally.
The deference of this voltage control the
output current of error amplifier.
D701 to D704 and C704 from DC supplier
circuit. 0701 is current amplifier. R701 is
shunt resistor. 0701 and R701 transfer cur-
rent from
DC circuit to road. R703 is for
minimum temparature drift.
C705 and C706
is noise filter condenser.
Output voltage is fixed by adjusting VR706
variable resistor.
1-2) Horizontal and Vertical processor IC202
1-2-1 Horizontal processor
IC202 perform following functions.
• Horizontal oscillator
• Sync separator
• Horizontal predriver
6
• Horizontal AFC
• Shunt regulator
The sync signal
is inverted by inverting
transistor 0301 and
is fed back into pin15
of
IC202 and flyback pulse into pin14 of
IC202.
This two signal are compared and the circuit
is locked
to a correct frequency and phase.
1-2-2 Vertical processor
IC202 performs following functions
• Vertical oscillator
• Vertical predriver
• Vertical output
• Flyback generator
There are two Vertical control functions.
One is V-SIZE control, the other is V-
UNEARITY control.
To control
V-SIZE, turn the VR219(MDA
MODE), VR220(CGA MODE).
To control V-UNEARITY, turn the VR221.
1-3) Horizontal output stage 0303
0303
is horizontal output switching transis-
tor which closed during the scan period
and
open during the flyback. It receives drive
signal from IC202 through transistor 0302
and horizontal drive trans T301.
The flyback period is determined by
resonance of
C409 deflection yoke. C409
makes the necessary S-correction.
Because ofthe losses
in the deflection yoke,
a linearity correction
is required.
This
is achieved by L402. ·The horizontal
screen can be varied by adjusting
L401.
The high voltage of 13Kv for CRT anode is
also generated in flyback transformer by
using flyback
pulse.
1-4) Dynamic focus
0401 (BUV46 or KSC 5021) is used to
provide dynamic focus voltage which
is
added to G4 voltage of the CRT.
This voltage is needed to change G4 voltage
according to the angle of the beam.

l-S) Video circuit
This circuit performs following functions.
• Video input buffer (1C501 :74LS07)
• Cascade amplifier (OS03, 0801)
• Contrast control circuit
(OSOl, VRSll,
0509)
If only video signal input into the
ICS01,ICSOl delivered to cascade
ampl ifier(OS03, 080 1)
If only intensity signal input into the ICS02,
1C502 delivered to cascade amplifier (OS03,
0801). CONTRAST CONTROL is operated
by
OSOl,OS09, VRSll from a cascade video
amplifier which circuit output is applied to
cathode pin of the
CRT.
1-6) CRT board
it contains video amplifier transistor 0801
and CRT socket.
1-7) Power: board
This board contain
fuse.
IMPORTANT: When replacing the power
supply, make sure that the green ground
wire
is properly attached to the make sure
that the fuse
is of the same type and rating
as original.
7

ALIGNMENT INSTRUCTIONS
PLEASE READ BEFORE ATTEMPTING SERVICE
1. Line voltage must be kept within 10% of the rated
voltage.
2. When operating at AC voltage, you must adjust
DC B+ voltage. To get collect B +, mode is to
be MDA. and then check B+ which is 12v ±0.1v,
if not, adjust VR706.
3. Do not discharge, ARC, or measure high voltage
when high voltage lead is connected to CRT.
Discharge 2nd anode of CRT only after high
voltage lead has been disconnected. Do not dis-
charge high voltage
lead at any time. This may
results damage to transistor.
4. While the monitor is in operation, do not attempt
to connect or disconnect any
wires.
5. Disconnect all power before attempting any
repair.
6. When the power is on, do not attempt to short
any portion of the circuit.This shorting may cause
damage to the transistors
in the receiver.
ADJUSTMENT
Apply power and video signal(alpha-numeric infor-
mation) to the data display.
CENTERING
1. Loosen the deflection yoke clamp and carefully
move·the yoke on·the neck of the CRT as far
forward
as possible. Rotate the yoke until the top
and bottom edges of the raster are straight.
Tighten the clamp.
2. Center the raster by rotating the centering rings.
B+ADJUSTMENT
1. Operate the monitor in MDA MODE.
2. Connect the plus pole of DVM (Digital multi meter)
to yellow wire which attached connect registor
and connect the other pole
(GND) to chassis
frame.
3. Rotate the B+ voltage adjusting control (VR706)
to provide DC 12V. (Tolerance is ±0.1v)
8
SUB-BRIGHTNESS
1. Set contrast(VR511) control to maximum and
brightness(VR415) control about 90 degrees
counterclockwise from fully clockwise portion.
2. Adjust sub-brightness control(VR411) at visual cut
off of the
raster.
3. You could change the brightness by another
method
in only MDA. To see more or less bright-
ness, you turn VR416.
HORIZONTAL FREQUENCY ADJUSTMENT
( Instrument in use : frequency counter and scope
probe )
1. Connect the PLUS pole of the scope probe to
brown wire of
DY and GND pole to chassis frame.
2. Without input signal, adjust the horizontal frequen-
cy control(VR315)
so that the horizontal frequency
is 18.00KHZ. (Tolerance is ±100 Hz)
VERTICAL FREQUENCY ADJUSTMENT
( Instrument in use : frequency counter, scope
probe )
1. Connect the GND pole of the scope probe to
chassis frame
and the scope probe to DY pin
connected to yellow wire.
2. Without input signal, adjust the vertical frequency
control
(VR223) so that the vertical frequency is
41HZ. (Tolerance is ±1 Hz)
HORIZONTAL WIDTH ADJUSTMENT
Adjust the horizontal width control (L40 1) so that the
horizontal width of displayed pattern
is .230mm.
(Tolerance is ±3 mm)
VERTICAL SIZE ADJUSTMENT
Adjust the vertical size control(VR219,VR220) so that
the vertical of displayed pattern is 170mm.
(Tolerance is ±3 mm)
Height control VR219 (IN MDA MODE)
Height control VR220 (IN CGA MODE)

VERTICAL LINEARITY ADJUSTMENT
Adjust the vertical linearity control (VR221 } for the
best linearity.
HORIZONTAL POSITION ADJUSTMENT
Adjust horizontal position control(VR316} so that the
image(or test pattern} is placed on the center of the
screen.
c:[] VR221
c:[] VR220
c:[] VR219
c:[] VR4 I I
VR316
@ L402
\ij7 VR706
~
VR223
~R404
~
VR315
ALIGNMENT PARTS LOCATION
9
FOCUS ADJUSTMENT
Adjust focus control(VR404} for providing the best
focus.
CRT NECK COMPONENTS LOCATION

DISASSEMBLY INSTRUCTIONS
REAR COVER REMOVAL
1. Place the monitor upside down.
2. Remove 2 screw A.(fig1)
3. Pull the REAR COVER backward as pushing the 2 points B in the direction of the arrows to separate from
the
FRONT COVER.
CRT ASSY/CHASSIS FRAME ASSY REMOVAL
1. Remove the CRT'S anode cap 1 from the CRT.
2. Remove the CHASSIS-FRAME from the FRONT CABINET.
NOTE: CRT must be discharged according to the CRT discharge procedure in the important safety
precaution.
FIGURE B. PCBS
~/~
1 (MATERIAL STEEL PLATE) FIG 2
FIG 1
10

EXPLODED VIEW
MD-1467Z
17
6
5
4
3
11
21
49
6
14 ,
"~
3
35
45
12

EXPLODED VIEW PART LIST REF
NO
DESCRIPTION
PART NO
Q'TV REMARKS
34 TRANSISTOR;KSA1010 2149-102-240 1
REF
NO
DESCRIPTION
PART NO
a'TV
REMARKS 35 HEATSINK-TR,POWER;AL050S-H14 T1.8 5682-705-910 1
1 KNOB-POWER;PPO VO BGE MD-1467 7622-701-610 1 36 ASSY-MAIN, PWB OM904-000-2530 1
2 SPRING-COIL;SUS-302 WPA
P10.5
6674-713-710 1 37 SCREW-TAP,PH;2S-3X8
FE FZY W/WASHER 7154-230-081 7
3 COVER FRONT;PPO VO BGE
OOOZZZZBC
6000-706-010 1 #50924
38 ASSY-POWER,PCB OM905-000-1760 1
4 SCREW-RH;M3X8 FE FZY 7048-130-081 2 39 SCREW-TH; +M4X8 FE FZY 7028-140-081 1
5 SWITCH-PUSH;ESB 8213V 3529-702-210 1 40 SCREW-TH; +M4X8 FE FZY 7028-140-081 1
6 ASSY-LED
OM905-OOO-2750 1
41 TRANS-POWER;P:120V S:16.2V LOAD:1.5A 2869-301-910 1
7 SUPPORT-CHASSIS;NOYRL PX-1005 PPO VO BGE 6460-700-110 1
#50924
42 SCREW-PH;M4X25 FE FZB 7008-140-253 1
8 ASSY-CONTRAST, VR;MZ467* OM905-000-2880 1 43 HOLDER-CORD;NOLYL
PX-l005 VO BGE 00 6601-703-020 1
#50924
9 ASSY-BRIGHT, VR;MZ467* OM905-000-2870 1 44 SCREW-TAP,FH;2S-4X15
FE FZW 7118-540-152 2
10 KNOW-VR;PPO VO BGE 7622-701-510 2
#50924
45 COVER-BACK;PPO VO BGE 6000-709-010 1
#50924
11
CRT-MONOCHROME;M32ECB2LA 2019-133-910 1 46 LABEL-LA
TING;POLYESTER TO.l66 8033-726-130 1
12 SCREW-TAP,TH;2S-4X20
FE FZY 7128-540-201 4 47 POWER-CORD,AC ASSY 3053-815-030 1
13 WASHER-PLAIN;165216 FE FZV 7304-101-190 4 48 CABLE-SIGNAL;ASSY 3052-400-720 1
14 EARTH-PLATE;PBS3 SP-H TO.3 4554-701-010 1 49 SHILD-VR;SPTE TO.25 4543-705-210 1
15 DY;DMK-1493AL 2439-056-710 1 50 EARTH-PLATE;PBSP TO.3 4553-700-410 1
16 CRT PWB, ASSY; OM904-000-2540 1
51 RUBBER-SUPPORT;NEPRENE RUBBER 8464-703-210 1
17 SHIELD-CASE;SPTE TO.306 4543-703-110 1 52 WASHER-PLAIN;104512
SPC-1 FZY 7304-101-040 1
18 SCREW-RH;M4X8 FE FZY 7048-140-081 3 53 STAND-ASSY;MD-1467 8302-700-910 1
19 WASHER-TOOTHED;B PI6XPI4 7328-204-001 2
20 CHASSIS-FRAME;SECC TO.8 6021-702-510 1
21
SCREW-TAP, RH;2S-3X8 FE FZY 7148-530-081 4
22 HOLDER-CEMENT,R ;SHBG-l/SECC-1 TO.8 6604-117-432 1
23 R-CEMENT 1
039-927-100 1
24 HEATSINK-TR,HORIZ;AL 050P T1.8 5682-705-710 1
25 NUT-HEX;1-M3
FE FZY 7028-113-001 2
26 WASHER-SPRING;PI3.0
FE FZY 7318-103-001 2
27 INSULATOR-TR;4.5-8D 2-3H N66 V-O 3934-103-110 2
28 SCREW-TAP,RH;2S-3X8
FE FZY 7148-530-081 2
29 PLATE-MICA;5-13X9 TO.09 RECT 3914-100-340 1
30 TRANSISTOR;BU406 2159-301-410 1
31
WASHER-REC;SBC-1 TI.5 NI
7304-701-110 1
32 SCREW-RH; +M3X10
FE FZY 7048-130-010 2
33 SHIELD-FBT;SPTE TO.306 4542-701-114 1
13
14

WIRING DIAGRAM AND PARTS LOCATION
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POWER CORD
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TROUBLE SHOOTING GUIDE
NO PICTURE APPEAR (NO POWER)
NO
[.. Check power cord and switch
~f-----------
I YES
C F701 Fuse open ]
NO --Failure
C705, 0701-, --l
0702, 0703, D704 I
Does 16.2V OC appear betwee~
C705 and GND? ~f---------------I
I YES NO
~_~_~_:_~_~_~_o_~_g~~_~_p;_a_r_on ____ ~~f-- ___ . ______ ~~L_ ~~ffiQml,~ml .~
Check signal input and turn NO I
~
"brightness control" Signal cable loose
clockwise to maximum.
YES
NO
I Failure
IC202,0302,T3011
. Check horizontal driver
.....J
YES
NO
Check horizontal output I Failure
0303,T302,H-D~
YES
NO
Check video pre-amp and Failure 0503,IC501
video processing circuit
YES
NO Does VDC appear
Check video output between collector of
0801 and GND ?
1
NO
YES
---,
Failure D403,0801 I
J
Qheck G2(630V DC) voltage NO
-j Failure D402,D404 I
YES
l Failure of CRT,CRT socket ~
18

VERTICAL TROUBLE
No vertical sweep display
YES
Check pin8
of IC202
YES
Failure of C210,V-DY
YES
Checkvert, synchronization
YES
Check signal input
of
vertical sync
YES
Failure of IC202,C204,C205
I HORIZONTAL TROUBLE I
I
r Check signal input
IYES
[- Does waveform appear at the
collector
of 0301 ?
IYES
I Check pin15 of IC202
I
I
I
I
J
NO
NO
NO
NO
NO
Failure IC202
Signal cable loose or bad
Signal cable loose
Failure
R301
Failure 0301, R303,
C301,R304
IYES NO
L- __ C_h_ec_k_p_i_n9 __ m~I_C_20_2 ________ ~J-------------------------[L-- ___ F_a_ilu_r_e_IC_2_0_2_,IC_1_0_1 ____ __
YES
I Does drive pulse appear at
L base of 0303 ?
YES
Does 20V appear between the
pin4
of T302 and ground ?
IYES
CCheck DY,T302,L401 ,L402,0303]
NO Failure R313,T301,Q302
NO Failure
D301 ,C404
19
MDA MODE ERROR
[.
~---.---~ I
Check the PC's video card I
mode switch setting ~
I YES
Does DC 3V appear at the
pin3
of IC201 ?
I YES
collector of 0101 ?
l
I
I Does
OV appear at the
--_--,--------------------l
IYES
i Does DC 12V appear at the
collector
of 0103?
IYES
Replace IC201,IC202,REY102
CGA MODE ERROR
Check the PC's video card
mode switch setting
YES
Does DC 11.5V appear at the
collector
of 0101 ?
YES
I-
I Check IC101, IC202, REY102
L or replace it.
MODE CHANGE ERROR
NO
NO
NO
NO
NO
NO
* When an error
occur in mode change, Check IC101 or IC201 carefully.
20
Change the MDA MODE
J Failure
C201 ,IC201 I
I
Failure 0101
r Failure
0102,0103
I
I
Change the CGA MODE
Failure 0101

SCHEMATIC DIAGRAM
MODEL NO: MZ46l*
CHASSIS NO: GSK
S.
nOl
T701
TRANS
AC
120Vo---·
1
60HZ
0.
75A
1
250Y r
II
(
VER
HOR
A301
410
1
,3
'00
1
0301
KSCB15
Rl07
'00
® ®
, 4(~1 .(
lREYl02 G2VJ
.- ____ '-'6 ul 11 \9
1 L
V. Rl06 ®
R203
1.5K
A711
100
R303
lk
C:O
'
iii
50V
0102Z
lN4148
lk
0103
KSC100B
'k
0102
KSC945
R104
,5k
R206
10k
0201
KSCB15
A304
330
NOTES
I.RESISTOR VALUES Aqe IN (0""1 k.I.OOOO~. M·1.000.0000~ ••
2. AlL AESISToqs AAE 1/40 EXCEPT O~EAE OMAOISE INDICATED.
3.41L CAPACtrOAS ARE' SOV EXCEPT WliEAE OTltERNISE INDICATED.
4.CAPACITORS VAlUES AAE PF UNLESS OT~AOISE INDICATED. U-UF-TEN TO THE MINUS SIX FAAAO.
IS •• ,... 1liE SV"BOL OF MOUND
6. nils 15 FUNO.Iit .... H ... L CIRCUIT OU,SA" .. .sOME PRODUCTION CHAlliSES MAY BE MADE .,lTIiOUT REVISION OF TIfE DIAGRAM.
,
21
306
68k
G
M
I
R31
2.7k
HC
L301
U5MH
0201
lN4002
Cloa
332
IOOV
I8J
,
0302
D400F
~
R314 R315
,
I WAR NI N G: '~IS EQUIPMENT CONTUNS SAFETY CRITICAL COMPONENTS All P~TS SHOON 1M T~E ~AQE ~EAS
OF T~E SC~EMATIC AAE SAFETY CRITICAL FOR CONTINUED SAFETY AEPLACE SAFETY CAITICAL
COMP(JNEIr(TS ONLY WITH "ANUFACTUAES RECOMMENDED PARTS REFER TO PAATS LIST FOR EXACT REPLACEMENTS.·
AVERTISS MEN T: 'CEl EQUIPMENT EQUIPE DE COMPOSANTS CRITIQUES POUR LA SECUAITE TOUTES LES PIECES INOIIlUEES
DANS LES ZONES CMaAEES OU SC~EMA SONT CAITIQUES POUR LA SECURITE POUR IlAINTENIA LE DE6AE DE
SECUAITE DE LAPPAAEIL NE AEMPLACEA LES CONPONENTS OONT LE FUNCTI_EMENNT EST CRITIIIUE
POUA LA SECUAITE QUE PAA DES PIECES REC_ANOEESPAA LE FABRICANT CONSUL TEA LA NOIIEIfCLATURE DES
PIECES POUR TAOUVEA LES PIECES DE REC~AN&E UACTEA.·
r .r
A G B INTENSITY VIDEO
0505 ,.4'48
0506 ,.4ua
0507 ,.4148
050J-+--<I.--+-+ C
'-----{E
;; ,...!!-+-
~ '2 0501
....
....
,.4ua
11
10
H-OY
R4tt 0401
820 I16P,5J
1/20
L402
H-LIN
,.4 .. 8
0503
tN4U8
R503
560
.1 HV
J
R407
0402
3.3 _01-12
1/20
0504
lN4148
R502
330
...
VB
0512
{N4US
R504
'.8K
, ,
r VE
Gl
2N3906
R510
1:
0501
,..--"II~l'
VR511 1
a500
a20
-
~. 10509
[hCONTRAST
0502
2N3906
VI
G2
A513
180
0503
2N390~
n
,
~a~I~03
~a9
G4
CRT
AMBER
GREEN
WHITE
HV
..
R401 R402
270k 270k
0504 t:l\
2N3904 l~
A520
:~n ~Irv iii; ~~~5J
t---+-e--+e.--_~
R40a
0403
,/20 1/20 FOCUS
L T302
0301
_306
3.3
tl20
R409
4.7
1/20
I16P,5J
0404
R6PtDS
C407
47U
IBOY
A4tO
56K T ... T
~
stOOk
BRIGHt
.n
V,roW
~3~OsUB-BRI6HT
P
YR4t&
500K
K)----'
22
Q401
BUV46
C40t R403 VA .. 04
t--n- ............ ..,.,..-~2.5M
'03 680k
,KV
R405

PRINTED CIRCUIT BOARD Bottom View
Main PC Board
Top View
CRT PC Board
Power
PC Board Top View
Bottom View
Top View Bottom View
24
23

WAVEFORMS (eGA)
1lf\-
JV\
700V p-p 133V P-P 290V
p-p
30V p-p 1.4V p-p
480V P-P e------------..
14V P-P
180V P-P
3.4V P-P
42V P-P 111
3.5V P-P
25
26

WAVEFORMS (MDA)
JV\_
JV\
660V p-p
120V p-p
280V p-p 28V P-P 1.4V
p-p
460V P-P .---------...
330V P-P
14V P-P
180V P-P
7V P-P
JlIII[ -
38V P-P
3.SV P-P
27
28