The information in this document is subject to change without notice.
SAFETY PRECAUTION
The design of this product contains special hardware, many circuits and components specially for safety purposes.
1.
For continued protection, no changes should be made to the original design unless authorized in writing by the
manufacturer. Replacement parts must be identical to those used in the original circuits. Service should be
performed by qualified personnel only .
2.
Alterations of the design or circuitry of the products should not be made. Any design alterations or additions will
void the manufacturer's warranty and will further relieve the manufacturer of responsibility for personal injury or
property damage resulting therefrom.
3. Many electrical and mechanical parts in the products have special safety-related characteristics. These
characteristics 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 the parts list of Service manual. Electrical components
having such features are identified by mark “ ! ” on the schematics and ! on the parts list in Service manual. The
use of a substitute replacement which does not have the same safety characteristics as the recommended
replacement part shown in the parts list of Service manual may create shock, fire, or other hazards.
Use isolation transformer.
4.
The chassis and any sub-chassis contained in some products are connected to the primary circuit of the A C
power line. An isolation transformer of adequate cap acity should be inserted between the product and the AC
power supply point while performing any service on some products when the primary circuit of the AC power
supply is exposed.
The high voltage applied to the picture tube must conform with that specified in Service manual. Excessive high
5.
voltage conditions should be kept to a minimum, or should be prevented. If severe arcing occurs, remove the AC
power immediately and determine the cause by visual inspection (incorrect installation, cracked or melted high
voltage harness, poor soldering, etc.) T o maint ain the proper minimum level of soft X-ray emission, components
in the high voltage circuitry including the picture tube must be the exact replacements or alternatives approved
by the manufacturer of the complete product.
6.
Isolation Check
(Safety for Electrical Shock Hazard)
After reassembling the product always perform an isolation check on the exposed metal parts of the cabinet
(video input and output terminals, control knobs, screwheads, control shafts, etc.) to be sure the product is safe
to operate without danger of electrical shock.
Dielectric Strength T est
(1)
The isolation between the AC primary circuit and all met al parts exposed to the user , particularly any exposed
metal part having a return path to the chassis should withstand a volt age of 1,500V AC(r .m.s.), 20mA(current
sensitivity) for a period of one minute.
This method of test requires a test equipment not generally found in the service trade.
(2)
Leakage Current Check
Plug the AC line cord directly into the AC outlet (do not use a line isolation transformer during this check.).
Using a “Leakage Current Tester”, measure the leakage current from each exposed metal part of the cabinet,
particularly any exposed metal part having a return path to the chassis, to a known good earth ground (water
pipe etc.). Any leakage current must not exceed 3.5mA AC(r.m.s.).
i
Alternate Check Method
Plug the AC line cord directly into the AC outlet (do not use a line isolation transformer during this check.). Use an
AC voltmeter having 1,000 ohms per volt or more sensitivity in the following manner. Connect a 1,500 910W resistor
paralleled by a 0.15uF AC-type capacitor between an exposed metal part and a known good earth ground (water
pipe etc.).
Measure the AC voltage across the resistor with the AC voltmeter . Move the resistor connection to each exposed
metal part, particularly any exposed metal part having a return p ath to the chassis, and measure the AC voltage
across the resistor. Now , reverse the plug in the AC outlet and repeat each measurement. Any voltage measured
must not exceed 2.45V AC(r .m.s.). This corresponds to 3.5mA AC(r .m.s.).
AC VOL TMETER
(HA VING 1,0009/V OR MORE SENSITIVITY)
0.15uF AC-TYPE
GOOD EARTH GROUND
1,5009 10W
PLACE THIS PROBE ON
EACH EXPOSED METAL
PART
ii
1. SET-UP ADJUSTMENTS
The following adjustments should be made when a complete realignment is required or a new picture tube is
installed.
<Required measuring equipment>
Signal generator (Programmable video generator)........................ Leader 1604A
DC voltmeter (300V DC range)
Note: Digital multimeter can also be used.
High voltage probe (0-30kV DC)
Color analyzer.......................................................................... Minolta CA-100
Electric field meter.................................................................... Combinova EFM 100
Scale (Two 50cm scales put together so that no visual aberration occurs.)
Frequency counter
Digital wattage meter
Degausser
Interface adapter (Iiyama handmade)
Short-connector (Iiyama handmade)
<Preparation>
Place the monitor without tilting.
1.
Connect the signal cable from the signal generator to the monitor.
2.
Face the CRT screen to east so as not to be influenced by magnetic force.
3.
Turn ON the Power Switch, and degauss the entire screen with degausser .
4.
Perform adjustment by setting the brightness to center and the contrast to maximum, except where
5.
specifically indicated.
Receive MODE 5 and turn ON the Power Switch. Perform adjustment after a warm-up of at least an
6.
hour.
Adjustment data is automatically saved in the memory when the on screen display disappears or
7.
another signal is received.
Note: This monitor should be checked and adjusted by connecting it to a signal generator, then entering
and running the timing charts both below and of Chapter 2.
Comp
–
–
–
–
Sync
on
green
–
–
–
–
36.76
33.39
1 1.76
1 1.43
fH
(kHz)
27.3
30.0
85.0
87.5
The resolutions are only for your reference when using Leader 1604A.
*
Resolution*
608×420
640×480
368×1360
544×1360
Sync polarity
V
H
N
N
N
N
P
N
N
N
Horizontal (µsec)
B
A
4.41
2.50
1.20
1.16
2.21
0.39
1.41
1.38
- 1 -
C
D
27.94
30.05
8.66
8.38
E
2.20
0.45
0.49
0.51
O
16.652
16.661
16.663
16.196
Vertical (msec)
P
0.074
0.067
0.047
0.046
Q
0.771
0.567
0.587
0.571
R
15.439
15.526
15.994
15.545
S
0.368
0.501
0.035
0.034
ADJUSTMENT MODE
There are two different modes available to adjust the monitor as described below . The adjustment with ‘o’ in front
of the title are only available under User Mode. The adjustments with ‘n’ in front of the title are only available under
Factory Mode. Y ou can perform the other adjustment s by either User or Factory Mode. Please change the mode
as required.
USER MODE:
Turn ON the Power Switch and you are in the User Mode.
FACT ORY MODE: There are two ways to enter the Factory Mode.
1.Turn OFF the Power Switch. Short between pins 2 and 4 of P803 connector on the PWB-MAIN with
a short-connector. T urn ON the Power Switch and you are in the Factory Mode. The following Factory
Mode Menu appears on the screen when you press the MENU Button. Turn OFF the Power Switch and
remove the short-connector from P803 connector to exit.
short
P803
2. In the adjustment menu, select "Function" on the Main Menu and then select "Language" on the Sub-Menu.
Follow the flow chart below and you are in the Factory Mode. Turn OFF the Power Switch to exit.
CRT
ê
CRT face
PWB-MAIN
P803
connector
DH
T1
VD
T2
RC
HD
V
V
C
S
F
f
RG
CT
BC
BG
DP
T3
The menu items in the Factory Mode are as follows:
Pincushion
Trapezoid
Parallelogram
Pinbalance
Side pin Top
Side pin Bottom
Pinbalance T op
Pinbalance Btm
Cutoff red
H-size bias
Cutoff blue
DBF Para
DBF Phase
V DBF
H moire
V moire
H convergence
Tilt-Dy
V linear side
V linear corner
Red gain
Temp cont
Blue gain
Degauss
DA TEST 1
DA TEST 2
DA TEST 3 *
* DA TEST 3 helps you to perform H/V-BLANKING and H-CONVERGENCE / TILT -DY confirmations in
this SET-UP ADJUSTMENTS. The following items are displayed automatically in turn.
1. H-convergence è 2. T ilt-dy è 3. H/V-blanking
- 2 -
1-1. ANODE VOL TAGE adjustment [PWB-MAIN]
WARNING !
VR501 (HV-ADJ) has been carefully factory-adjusted for each unit in order
to satisfy regulations regarding X-radiation.
Further adjustment on VR501 shall not be performed.
In case of adjustment, the adjusted position of VR501 must be fixed by a
soldering iron to prevent it from rotating.
1)
Receive a cross-hatch inverted signal of MODE 5.
2)
Turn OFF the Power Switch.
3)
Connect a high-voltage probe between CRT anode and GND (chassis).
4)
Turn ON the Power Switch.
5)
Adjust the high-voltage to 25.0±0.1kV with VR503 (HV -ADJ).
6)
Confirm the variation of high-voltage is within ±0.2kV when receiving MODE
2 and MODE 6 respectively .
7)
Turn OFF the Power Switch and remove the high-voltage probe.
1-2. SCREEN VOL TAGE adjustment [PWB-MAIN]
1)
Receive a cross-hatch inverted signal of MODE 5.
Voltage
VR503
HV-ADJ
2)
Turn ON the Power Switch.
3)
Connect a high-voltage probe between the SC connector on the PWBVIDEO and GND (chassis).
Adjust the screen voltage to 630±10V with SCREEN VR located lower of
4)
T501 (FBT).
Note: SCREEN VR should not be turned after the adjustment above.
1-3. FH-LIMITER confirmation
n
1)
Receive a cross-hatch inverted signal of fH 27.3kHz.
2)
Confirm that the picture disappears. Also, make sure the horizontal
oscillation frequency is within the specified range: 59-61kHz.
3)
Receive fH 30.0kHz and confirm that the picture is synchronized.
4)
Receive fH 87.5kHz and confirm that the picture disappears. Also, make
sure the horizontal oscillation frequency is within the specified range above.
5)
Receive fH 85.0kHz and confirm that the picture is synchronized.
6)
Turn OFF the power of signal generator and confirm that the picture
disappears. Also make sure the horizontal oscillation frequency is within
the specified range above.
T501(FBT)
Voltage
E
R
E
C
S
N
7)
Remove the frequency counter.
- 3 -
Picture
Picture
Raster rolling
Raster tearing
1-4. H-BLANKING confirmation
n
1)
Receive a cross-hatch inverted signal of MODE 5 or MODE 6.
2)
Minimize the horizontal size with the front buttons.
3)
Select DA TEST 3 and press the MENU Button so that the automatic
confirmation program starts.
4)
Confirm that X of the right hand side figure is as follows: X </= 3.0mm.
5)
Adjust the horizontal size roughly with the front buttons.
1-5. V-BLANKING confirmation
n
1)
Receive a cross-hatch inverted signal of MODE 5 or MODE 6.
2)
Adjust the vertical size and position (V-size and V -position) of the picture
roughly with the front buttons.
3)
Select DA TEST 3 and press the MENU Button so that the automatic
confirmation program starts.
4)
Confirm that the back-raster is not rolling or tearing at the top.
5)
Confirm that no retrace line is over the picture.
Raster rolling
x
Picture
1-6. V-LIN adjustment
n
1)
Receive a cross-hatch inverted signal of MODE 5.
2)
Adjust the vertical size to 232.5±10mm.
3)
Adjust the vertical linear corner (V linear corner), so that difference between
A and B of the right hand side figure is as follows: | A–B | </= 0.5mm
4)
Adjust the vertical linear side (V linear side), so that A, B and C are almost
equal.
1-7. H-CENT adjustment [PWB-MAIN]
n
1)
Receive a cross-hatch inverted signal of MODE 6.
2)
Adjust the horizontal size and position of the picture roughly with the front
buttons.
3)
Maximize the brightness so that the back-raster appears on the screen.
4)
Set S501 to the right, center or left so that A and B in the right hand side
figure are almost equal.
5)
Return the brightness to center indication (adjustment range: 128).
S501
Right
Back-raster
A
Picture
Bezel
A
C
B
Left
B
1-8. TIL T -DY adjustment
n
Receive a cross-hatch inverted signal of MODE 5.
1)
Adjust the tilt deflection yoke (Tilt-Dy) with the +/– Buttons so that X of the
2)
right hand side figure is as follows: | X | </= 0.5mm.
X
- 4 -
1-9. PICTURE SIZE, POSITION AND DISTORTION adjustment (Criteria)
n
1)
Receive a cross-hatch inverted signal of MODE 5.
2)
Adjust the picture size and position to the specified setting below.
H-size: 310±4mm
V-size: 232.5±4mm
3)
Correct the side distortion with the front buttons so that X of the right hand
H-position: | A–B |<4mm
V-position: | C–D |<4mm
side figure is as follows: | X | </= 3.0mm.
Pincushion
Trapezoid
Pinbalance
1-10. PICTURE SIZE, POSITION AND DISTORTION adjustment
n
1)
Receive a cross-hatch inverted signal of all preset modes respectively .
2)
Adjust the picture size and position roughly with the front buttons to the
Parallelogram
Side pin Top / Bottom
Pinbalance Top / Bottom
reference settings below.
H-size: 310±10mm
V-size: 232.5±10mm
3)
Correct the Pincushion and Trapezoid distortion with the front buttons so
H-position: | A–B |<8mm
V-position: | C–D |<8mm
that X of the right hand side figure is as follows: | X | </= 3.0 mm.
Notes: 1. No other adjustment items for distortion than the above should
be adjusted.
2. The picture should be within the bezel.
C
A
Picture
D
X
XX
Side pin Top / Bottom
Side pin Top / Bottom
X
Pincushion
Trapezoid
Pinbalance
Parallelogram
B
Bezel
1-11. RESET confirmation
o
1)
Receive a cross-hatch inverted signal of MODE 5.
2)
Change the horizontal position (H-Position) roughly with the front buttons.
3)
Perform Reset.
4)
Confirm that the adjustment data above is reset to the factory setting.
Pinbalance Top / Bottom
- 5 -
1-12. Automatic COLOR adjustment s
n
WARNING:
Do not change the horizontal and vertical sync signal or the frequency
while the automatic COLOR adjustments are underway .
Color analyzer setting:
Luminance unit switch: cd/m
l
B.P.S. DIP switch: 9600 (1000)
l
Turn ON the color analyzer switch and press 0-CAL switch before use.
l
1)
Be sure to enter the Factory Mode by using the short-connector.
2)
Connect the interface adapter from RS-232C of the color analyzer to the
short-connector.
3)
Receive a white window signal of MODE 5.
4)
Turn OFF the R, G and B outputs on the signal generator .
5)
Apply a color analyzer probe to the center of the screen.
6)
Turn ON the Remote Switch of the color analyzer so that the automatic
CUT-OFF adjustment start s.
7)
Turn ON the R, G and B outputs on the signal generator so that the
COLOR TEMPERATURE and CONTRAST LIMIT adjustments start
automatically .
cd/m²
2
Luminance unit switch
1
0
B. P. S. DIP switch
fL
<COLOR TEMPERATURE>
The X and Y specified readings of the color analyzer are as follows:
CT 1 (9300K)
X: 0.283±0.008
Y: 0.297±0.008
<CONTRAST>
The specified contrast range is 140±5cd/m
2
Note: In case that the contrast is not within the specified range above,
repeat 4) to 7).
8)
The OSD disappears.
9)
Press the MENU Button so that the OSD appears.
10)
All adjustment data is stored when the OSD disappears.
11)
Turn OFF the Remote Switch of the color analyzer .
Note: The adjustments above can be repeated by turning OFF and ON the
Power Switch.
1-13. GRA Y SCALE confirmationn
1)2)Receive a 16-gradation gray scale signal of MODE 5.
Make sure the 15th gradation on the gray scale is barely visible when the
16th gradation (back raster) is not visible at all.
- 6 -
n
1-14. BRIGHTNESS adjustment [PWB-MAIN]
1)
Receive an entire white raster signal of MODE 5.
2)
Apply a photometer to the screen center.
3)
Adjust VR502 (ABL-ADJ) so that photometer reads 105±5cd/m2.
1-15. SYNC SIGNAL INPUT confirmation
n
1)
Receive a cross-hatch inverted signal of MODE 5.
2)
Select composite and sync on green signal inputs respectively by the
signal generator.
3)
Confirm that the picture is displayed normally .
1-16. POWER MANAGEMENT confirmation
o
1)
Turn OFF the Power Switch and connect a digital wattage meter .
2)
Turn ON the Power Switch.
3)
Receive a cross-hatch inverted signal of MODE 5.
4)
Turn OFF the R, G and B outputs on the signal generator .
Brightness
VR502
ABL-ADJ
5)
Disconnect the H/HV and V cables.
6)
Confirm that the input wattage is 3W or less and the Power Indicator turns
to orange.
7)
Connect the H/HV and V cables and confirm that the picture appears.
8)
Turn OFF the Power Switch and remove the digital wattage meter .
9)
Turn ON the Power Switch.
1-17. H-CONVERGENCE, TILT-DY confirmation
n
1)
Receive a cross-hatch inverted signal of MODE 5 or MODE 6.
2)
Select DA TEST 3 and press the MENU Button so that the automatic
confirmation program starts.
3)
Confirm that vertical blue lines are diverged to the right and the picture tilts
to the left.
- 7 -
1-18. RASTER REGULA TION (DYNAMIC) confirmation
Back-raster
Picture
W
n
1)
Receive an entire white signal of MODE 6.
2)
Set the input signal by the signal generator as follows:
V-DISPLA Y -TIME: 150 V-POSI-TIME: 450
3)
Maximize the brightness.
4)
Confirm that ,W of the right hand side figure is 1.0mm or less when
turning the luminance volume on the signal generator to the maximum
and “1” respectively .
5)
Return the brightness to center indication (adjustment data: 128).
1-19. FOCUS [PWB-MAIN]
n
FOCUS-B
1)
Receive a green cross-hatch signal of MODE 5.
2)
Adjust FOCUS-A VR of T504 (FBT) to make the vertical lines sharpest at
points L, M and R as shown in Fig 1.
3)
Adjust FOCUS-B VR of the T504 to make the horizontal center line
sharpest at points L, M and R as shown in Fig. 1.
4)
If the focus at points T and M is as shown in Fig. 2, adjust V DBF in the
menu with the front buttons to make the horizontal lines have the same
thickness at points T, M and B. And adjust the FOCUS-B VR again to
make the horizontal lines sharpest at points T, M and B. (V DBF should
not be adjusted when focus at points T and M is optimum.)
5)
If the focus at points L and M is as shown in Fig. 3 or vice versa, adjust
DBF Para and DBF Phase in the menu with the front buttons to make the
horizontal center line have the same thickness at points L, M and R. And
adjust the FOCUS-B VR again to make the horizontal center line sharpest
at points L, M and R. (DBF Para and DBF Phase should not be adjusted
when focus at points L and M is optimum.)
6)
Repeat 2) to 6) until the focus is optimum.
7)
Confirm no focus variation on the entire screen.
8)
Check the focus with red and blue respectively .
9)
Receive a H-character signal and repeat 7).
10)
Repeat the FOCUS adjustments until the focus with red, green and blue
is optimum.
Apply a photometer to L (left) / R (Right), T (Top) and B (Bottom) in the
right hand side figure respectively.
3)
Confirm that the luminance difference is the 22.5cd/m2 or less.
T
2
L
VR501
C
B
Luminance
UNIFORMITY
R
- 9 -
White (S side)
2.3±0.2
7±0.4
7.6±0.4
(in mm)
S
N
*Magnet (890Z008A01)
1-22. ITC (Integrated Tube Component) adjustments
n
The following ITC adjustments should be made only when a new picture tube is installed*1, or convergence is poor.
All set-up adjustments above-mentioned must be completed before any further ITC adjustment is attempted.
Perform the following adjustments by setting H-convergence and Tilt-dy to center indication.
Notes: *1. Use the CRT (251Z063-03) for replacement of the CRT (251Z063-04).
*2. See Chapter 5 concerning parts list for the ITC adjustments.
*3. PURITY MAGNET should not be turned during the ITC adjustments.
< A705MT / i70A >
X
V
PURITY MAGNET*3
4-POLE MAGNET
6-POLE MAGNET
+
Y
h(t)
+
Y
+
Y
X
V
ê
CRT face
h(a)
V(a)
DEFLECTION
YOKE
SEPARATOR
LOCKING RING
BOW MAGNET
DIFFERENTIAL
COIL
< S705MT >
DIFFERENTIAL
COIL
X
V
PURITY MAGNET*3
4-POLE MAGNET
6-POLE MAGNET
X
V
+
+
Y
HB
Y
HC
+
Y
V
DEFLECTION
YOKE
ê
CRT face
SEPARATOR
LOCKING RING
BOW MAGNET
Before ITC adjustments:
Receive an entire white raster signal and turn ON the Power Switch. Perform adjustment after a warm-up of at least
an hour.
1-22-1. PURITY correction
Receive an entire red raster signal.
1)
Adjust the vertical and horizontal picture size to full-scan.
2)
Face the CRT screen to north and south respectively and degauss
3)
the entire screen with degausser.
Confirm that no color clash is visible.
4)
If any partial color clash, correct the purity with the *magnet
5)
*Magnet
(890Z008A01).
Note: Stick the magnet to the CR T with DF-T APE (890P329A10).
Perform degauss again.
6)
Repeat 4) to 6) until the purity is optimum.
7)
Fix the magnet with ACET A TE-T APE (890P306A10).
8)
Note: The magnet should be fixed away from the DY not to change
distortion or convergence.
- 10 -
<CRT screen>
<Back view of CRT>
DF-TAPE (890P329A10)
DY
Color clash
Anode cap
1-22-2. STATIC CONVERGENCE adjustment
Receive a red and blue cross-hatch signal.
1)
Adjust the 4-POLE MAGNET so that red and blue beams converge on the
2)
center cross lines.
Add green to the red and blue cross-hatch signal.
3)
Adjust the 6-POLE MAGNET so that red and blue beams converge with
4)
green beam on the center cross lines.
Repeat the adjustment until red, blue and green beams converge each
5)
other.
Fix the 4-POLE MAGNET and the 6-POLE MAGNET by turning the
6)
LOCKING RING.
Mark the 4-POLE MAGNET and the 6-POLE MAGNET with paint marker
7)
(090Z029A01) so that adjusted position is understandable.
R
B
G
R,B
R,G,B
R,B
B
R
G
R,G,B
1-22-3. BOW MAGNET adjustment
1)
Receive a red and blue cross-hatch signal.
2)
Adjust the BOW MAGNET so as to straighten an arched horizontal line.
Note: Must be careful not to misconverge vertical lines by this adjustment.
3)
Perform the 1-22-2. STA TIC CONVERGENCE adjustment so as to converge
the red and blue lines.
1)2)Receive a red and blue cross-hatch signal.
Adjust the DIFFERENTIAL COIL so that the horizontal cross line converge
each other.
1-22-5. YV adjustment
1)
Receive a red and blue cross-hatch signal.
2)
Adjust the specified YV volume so that red and blue beams converge
each other at the upper and lower edges of the horizontal line.
R
B
B
R
R
B
R,B
B
R
R
B
- 1 1 -
R,B
R,B
1-22-6. YH adjustment
1)
Receive a red and blue cross-hatch signal.
2)
Adjust the specified YH volumes so that vertical cross lines converge
each.
Y
h(t)
(251Z063-03)
YHC(251Z066-01)
R
B
Y
h(a)
(251Z063-03)
YHB(251Z066-01)
R
B
R,B
1-22-7. SCREEN-CORNER MISCONVERGENCE correction
Receive a red and blue cross-hatch signal.
1)
Affix a *ferrite sheet (890Z003A01/03/05) between SEP ARA TOR and CRT
2)
corresponding to the partially misconverged areas.
Note: Must be careful not to affect distortion by this correction.
Fix the ferrite sheet with ACET A TE-T APE (890P306A10).
3)
10
100
Ferrite
10
5
90
R
B
B
R
B
R
R
B
(890Z003A01)
70
(890Z003A03)
*Ferrite sheet
(in mm)
(890Z003A05)
- 12 -
Video
Sync
2. TIMING CHART
- 13 -
Mode
VESA Timing Name
640×400
1
640×480
2
640×480
3
800×600
4
B
@ 70Hz
@ 60Hz
@ 85Hz
@ 85Hz
C
fH
(kHz)
31.469
31.469
43.269
53.674
D
A
fV
(Hz)
70.080
59.940
85.008
85.061
E
Sync polarity
H
V
Comp
N
P
N
N
N
N
P
P
H-parameters
A: Total period
B: Sync.width
C: Back porch
D: Active video
E: Front porch
Sync
on
green
–
–
–
–
31.778
–
31.778
–
23.1 11
–
18.631
–
Q
P
R
O
S
V-parameters
O: Total period
P: Sync.width
Q: Back porch
R: Active video
S: Front porch
Horizontal (µsec)
A
B
3.813
3.813
1.556
1.138
C
1.907
1.907
2.222
2.702
D
25.422
25.422
17.778
14.222
E
0.636
0.636
1.556
0.569
O
14.268
16.683
1 1.764
1 1.756
Vertical (msec)
P
0.064
0.064
0.069
0.056
1.1 12
1.048
0.578
0.503
Q
R
12.71 1
15.253
1 1.093
1 1.179
S
0.381
0.318
0.023
0.019
5
6
1024×768
1280×1024
@ 85Hz
@ 75Hz
68.677
80.00
84.997
75.0
P
P
–
P
P
–
14.561
–
12.5
–
1.016
1.07
2.201
1.84
10.836
9.48
0.508
0.11
1 1.765
13.325
0.044
0.037
0.524
0.475
1 1.183
12.8
0.015
0.013
3. IC APPLICATION
Ref No.Description
Deflection circuit
IC301
IC401Vertical deflection output
IC501SLA5077Cushion-S switching FET array
Power circuit
IC803KIA7045 / M51951
IC901TEA1504Main power control
IC903LM317T12V regulator
IC904LM317T6.3V regulator (Heater voltage ON/OFF control)
IC905KIA431Feedback control
IC906KIA78DL05PI5V regulator
Microprocessor circuit
IC801
IC802E2PROM (Memory: 8K)
High voltage circuit
IC502
Video circuit
UPC1884
LA7840N
TMP86CP11N
24C08
H&V oscillator, Distortion / Size / Phase / DBF control
Specifications of Microprocessor are on next page.Note:
Video output
Power amplifier (Cut-off control)
- 14 -
Microprocessor specifications
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Name
GND
XIN
XOUT
TEST
VDD
MODEL SW
CS1
RESET
CS2
H-CONV
TIL T
SIZE
NC
CS3
CS4
NC
H-LIN
NC
KEY1
KEY2
VREF
Function
GND
12MHz X'TA L
12MHz X'TA L
GND
5V Vcc
Model switching (A705: Low, S705: High)
Cushion-S switching signal 1
Reset
Cushion-S switching signal 2
H-convergence
Tilt
H-size freq. correction voltage output
N.C.
Cushion-S switching signal 3
Cushion-S switching signal 4
N.C.
Linearity switching signal output
N.C.
Front +/– key signal input terminal (+: 0V , –: 2.5V)
Front Menu key signal input terminal
5V Vcc
Pin
42
41
40
39
38
37
36
DDC SDA
35
DDC SCL
34
EROM SDA
33
EROM SCL
32
I2C SDA
31
I2C SCL
30
29
28
27
26
25
24
DA TA-IN
23
DA T A-OUT
22
Name
V-IN
H-IN
V-OUT
H-OUT
CLAMP
NC
NC
LED1
LED2
PS1
DEG
PS2
CLK
Function
V-SYNC signal input
H-SYNC / COMP signal input
V-SYNC signal out
H-SYNC signal out
Video clamper
N.C.
N.C.
DDC Data input/output terminal
DDC Clock terminal
2
E
PROM Data input/output terminal
E2PROM Clock terminal
Upc1888/Pre/OSD/DA Data input/output terminal
Upc1888/Pre/OSD/DA Clock terminal
LED1 control
LED2 control
Main power off signal
Degauss control signal output
12V power off signal
Automatic adjustment Clock terminal
Automatic adjustment Data input terminal
Automatic adjustment Data output terminal
- 15 -
4. CIRCUIT DESCRIPTION
4-1. POWER SUPPLY circuit
(1) Normal mode
This circuit is an asynchronous switching power supply circuit with using IC901.
Switching frequency is determined on approx. 70kHz oscillation by resistance of R919.
IC905 detects the load of 27V output voltage from the T901 secondary and controls luminescence of PC901
(photocoupler). The 27V output voltage is fed back to pin 9 of IC901. The feedback voltage changes the output pulse
duty of pin 4 of IC901 and stabilize the output voltages from the T901 secondary .
The T901 secondary provides the following DC voltages:
Q 80V line:Supplied to the HIGH VOL T AGE OUTPUT and the CUT -OFF circuits and the VIDEO OUTPUT
IC as power source.
R 27V line:Supplied to the HORIZONT AL DEFLECTION OUTPUT (variable B voltage control) circuit a s
power source.
S 15V line:Supplied to the HORIZONTAL DRIVE and the SIGNAL CONTROL circuits and the VERTICAL
OUTPUT IC (+) as power source.
T –12V li ne : Supplied to the VERTICAL OUTPUT IC (–) as power source.
AC-IN
T902
R919
D901
IC901
14
8
6
7
T901
9
+
C909
Q901
113
4
5
5
3
2
10
13
12
15
14
16
17
18
+
+
+
INOUT
+
IC903
INOUT
IC904
+
INOUT
IC906
+
Q901Drainwaveform
80V
27V
15V
12V
6.3VCRTHEATER
5V
-12V
- 16 -
IC901Pin4outputwaveform
(2) Power management modes
Q Stand-by / Suspend state
The 12V line of the T901 secondary stops so that a load current decreases and the feedback voltage to pin 9 of
IC901 declines. The output frequency of pin 4 of IC901 is switched to 30kHz from 70kHz and it reduces a power.
Q901Drainwaveform
IC901Pin4outputwaveform
R Active-off state
Input voltage to IC906 is supplied from 80V line of T901 secondary when D914 (thyrister) is activated so that
IC901 is switched to burst transmission mode (intermittent oscillation).
Therefore, the output voltages of T901 secondary decline to approx. 7% of normal output voltage and it reduces
a power.
- 17 -
Q901Drainwaveform
IC901Pin4outputwaveform
4-2. PROTECTION circuit
This circuit is composed of the following protection circuits to prevent a damage to the monitor and X-ray radiation
when the monitor is inoperative.
When the circuit is in the following cases, pin 19 of IC301 turns to 5V and then the horizontal drive signal output
from pin 17 and the variable B control pulse output from pin 14 turn to “LOW” level (0V). It makes the HORIZONT AL
DEFLECTION OUTPUT and the HIGH VOL T AGE OUTPUT circuits stop.
The signal that the X-RA Y PROTECTION circuit is activated is sent to IC801 (Microprocessor) from IC301 by I2CBUS when pin 19 turns to 5V . IC801 receives the signal and then PS1 signal of pin 27 turns to “HIGH” level (5V) so
that the DC voltages except for the 5V line are turned off.
In case that the PROTECTION circuit is activated and the HORIZONT AL DEFLECTION OUTPUT , HIGH VOL T AGE
OUTPUT and MAIN POWER SUPPL Y circuit s are turned off, turn OFF and ON the Power Switch to recover .
The PROTECTION circuit operates in the following cases:
Q +B9 line:The voltage is 180V or more.
R X-RAY PROTECTION circuit:The high voltage is 29.9kV or more.
S ARC LIMIT circuit:The beam current is 2.5mA or more.
4-3. HIGH VOL TAGE CONTROL / OUTPUT circuit
The AFC pulse output from the HORIZONT AL DEFLECTION OUTPUT circuit is applied to pin 1 of IC502 and then
a control pulse synchronized with the frequency of the AFC pulse is output from pin 1 of IC502 PCS (primary
control system).
This circuit is to detect a feedback voltage from the FBT (flyback transformer), change the output duty of pin 1 of
IC502, and control the high voltage change due to the brightness changes.
IC502Pin1outputwaveform
Q521Drainwaveform
T504(FBT)Pin1waveform
- 18 -
4-4. DISPLA Y POWER MANAGEMENT circuit s
(1) Stand-by / Suspend st ate:
When receiving no horizontal or vertical sync signal for 6 seconds, the output voltage of pin 25 of IC801 turns
to 5V from 0V and Q903 is turned off. The output voltage of IC903 (12Vreg.) turns to 1.2V from 12V and then
the circuit controlled by 12V stops operation. Therefore, it keeps the power consumption 10W or less.
(2 ) Active-off state:
When receiving no horizontal and vertical sync signals for 6 seconds, the output voltage of pin 27 of IC801
turns to 5V from 0V and Q904 is turned on. The D914 starts operation and the output voltage of T901
secondary declines to approx. 7%. All circuits except for the 5V line stop and it keep s the power consumption
3W o r less. In this case, as an input voltage of IC906 is supplied from the 80V line, the circuit controlled by
5V is activated.
<Power save control signals>
Mode
Normal
St and-by
Suspend
Active-off
Sync signal
H,V-Sync, VIDEO: ON
V-Sync, VIDEO: OFF
H-Sync, VIDEO: OFF
H,V-Sync, VIDEO: OFF
PS1
IC801 pin 27
LOW
HIGH
HIGH
HIGH
PS2
IC801 pin 25
HIGH
HIGH
HIGH
LOW
Circuit
All circuits are activated.
12V circuit stops.
All circuits except for 5V line stop.
4-5. SYNC SIGNAL PROCESSING circuit
The input signal from D-SUB connector is input to pins 41 (H) and 42 (V) of IC801. The input sync signal is
waveform-shaped and output from pins 39 (H) and 40 (V), and then supplied to pins 26 (H) and 27 (V) to control the
horizontal and vertical deflection.
The input sync signal to IC801 is processed by SYNC SIGNAL PROCESSING circuit in IC801 as follows:
Q Detect the input sync signal presence
R Discriminate the input sync signal type: Separate / Composite
S Discriminate the sync polarity: Positive / Negative
T Count the frequency
Counting criterion: X'T AL 12MHz
- 19 -
4-6. VIDEO circuit
(1) Pre-amp
<VIDEO>
The video signal from D-SUB connector is input to IC201 pre-amplifier and then clamped by clamp signal
input to pin 19. The blanking signal input to pin 27 is synthesized with the clamped signal and then output
from pins 35 (RED), 32 (GREEN) and 29 (BLUE) respectively.
V-BLK signal:Remove the raster retrace line.
H-BLK signal:Remove the side raster rolling.
<ABL>
DC voltage input to pin 15 of IC201 controls the amplitude of the video output signal. Therefore, it controls the
FBT beam current.
ABL is activated (entire white raster):Approx. 3.5VDC at pin 15
ABL is not activated (window):Approx. 4.1VDC at pin 15
The parabolic waveform is added to video output signal by synthesizing the H-DBF parabolic waveform from
Q517 and it corrects a luminance difference between the left and right side of the picture.
I2C-BUS controls D/A converter in IC201 as follows:
Q Contrast
R Sub-brightness
S R/G/B drive
T OSD contrast
U D/A output for the CUT -OFF circuit
(2 ) VIDEO-OUT and CUT-OFF circuit s
The video signal input to pin 9 (RED), 8 (GREEN) and 1 1 (BLUE) of IC203 is amplified by 13 times and then
output from pin 3 (RED), 5 (GREEN) and 1 (BLUE) respectively .
The cut-off and brightness control voltages output from pins 23-26 of IC201 are amplified by 17 times by
IC204 and the transistor. The DC voltage output from IC203 is added to the video signal and then supplied to the
CRT cathode grid.
CRTcathodewaveform
IC201outputwaveform
IC201pin15ABLinputwaveform
IC201pin19clampwaveform
- 20 -
4-7. CONTROL circuits
(1) HORIZONT AL / VERTICAL OSCILLA TION circuit
The sync signal input to IC301 is phase-sifted and converted to the waveform in IC301. The pulse synchronized
with the horizontal sync signal is output from pin 17 as horizontal drive pulse. The sawtooth wave synchronized
with the vertical sync signal is output from pin 4.
The pulse output from pin 17 generates a frequency locked to the input signal under the following
conditions:
Q The horizontal sync signal is input to pin 26.
R The vertical sync signal is input to pin 27.
S The feedback pulse (AFC pulse) of the HORIZONTAL DEFLECTION OUTPUT circuit is input to pin 18.
IC301 is auto-sync system and adjusts the horizontal frequency automatically make the vertical sync
signal input to pin 27 trigger. In case that the AFC pulse is not input, the output pulse from pin 17 is unlocked
and the horizontal picture size changes with keeping it small.
(2) HORIZONT AL SIZE and DISTOR TION CONTROL circuits
The variable B voltage control pulse synchronized with the horizontal sync signal is output from pin 14 of
IC301. The horizontal size control voltage and distortion control parabolic wave output from pin 5 are input
to pin 11 and then the output pulse o f pin 14 controls the horizontal size and distortion as follows:
Q H-size:The output duty of pin 14 is varied by the DC voltage input to pin 1 1.
R Distortion: The parabolic wave (AC component) input to pin 1 1 is synthesized with the output pulse of
pin 14.
ACcomponent...Distortion
DCcomponent...H-size
IC301pin5output
Pin26:H-syncsignalinput
Pin18:AFCpulseinput
Pin14:VariableBcontrolpulseoutput
Pin17:H-DRIVEpulseoutput
- 22 -
4-8. HORIZONT AL DEFLECTION circuit
The horizontal drive pulse output from pin 17 of IC301 is pre-driven by Q503 and T501 and then supplied to Q504
(H-OUT) base as a current.
The current is amplified by Q504 and then supplied to the deflection yoke as a deflection current to control the
horizontal deflection.
Q503Gatewaveform
Q503Drainwaveform
Q504Correctorwaveform
4-9. VERTICAL DEFLECTION circuit
The sawtooth wave output from pin 4 of IC301 is amplified by IC401 and then supplied to the deflection yoke as a
deflection current.
V-position is controlled by changing the DC component of the sawtooth wave output from pin 4.
The center voltage is determined by the reference voltage input to pin 4 of IC401 and the V -sawtooth wave input to
pin 5 of IC401.
Centervoltage
IC401pin2outputwaveform
- 23 -
4-10. DYNAMIC BEAM FOCUS (DBF) circuit
(1) H-DBF
The parabolic wave of horizontal period is output from pin 9 of IC301 and then amplified by approx. 18
times by Q518 and Q519. It increases up to approx. 500Vp-p by T503 and synthesized with Vparabolic wave and then added to the focus circuit of the FBT (flyback transformer).
CRTcathodewaveform(Hperiod)
T504(FBT)pin13:DBFhorizontalelementinput
(2) V-DBF
The parabolic wave of vertical period is output from pin 12 of IC350 and then amplified by approx.
100 times by Q520. It is synthesized with H-parabolic wave.
CRTcathodewaveform(Vperiod)
T504(FBT)pin13:DBFwaveforminput
- 24 -
5. SERVICE PARTS LIST
The components identified by “ ! ” in this manual are critical
for safety .
Replace only with part number specified .
Abbreviations and Marks.......................................................................................