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P75

P75
SERVICE MANUAL
US Model
Canadian Model
UK Model
AEP Model
N. Hemisphere Model
S. Hemisphere Model
Australian Model
Chassis No. SCC-L07E-A

D-1H CHASSIS
SPECIFICATIONS

Picture tube 0.25 mm aperture grill pitch Power Consumption
17 inches measured diagonally Maximum 115W
90-degree deflection Nominal 100W, 341 BTU/h

Video image area (16" maximum viewing image) Deflection frequency Horizontal: 30 to 85 KHz
Approx. 329.5 x 243 mm (w/h) Vertical: 50 to150 Hz
(13 x 9 5/8 inches)
AC input voltage / current 100 to 120 V, 50/60 Hz, 1.8 A
Max. resolution Horizontal: Max. 1280 dots 220 to 240V, 50/60Hz, 1A
Vertical: Max. 1024 lines
(at 75 Hz Refresh Rates) Dimensions 424 x 422 x 428 (w/h/d)
(16.7 x 16.6 x 16.9 inches)
Standard image area Approx. 306 x 230 mm (w/h)(Mode 1-13)
Approx. 294 x 231 mm (w/h)(Mode 14-15) Mass Approx. 18.48 kg (40.8 lb.)

Input signal
Video Analog RGB (75 ohms typical)
0.7 Vp-p, Positive
Sync External HD/VD, Composite
Polarity Free TTL Design and specifications are subject to change without notice.
Video Composite (Sync on Green)
0.286 Vp-p, Negative

COLOR MONITOR

--1--
P75
POWER SAVING FUNCTION
NOTE: If no video signal is input to the monitor, the "NO INPUT SIGNAL" message appears.
After about 30 seconds, the Power Saving function automatically puts the monitor into
This monitor has three Power Saving modes. active-off mode and the indicator lights up orange. Once the monitor detects horizon-
By sensing the absence of a video signal from the tal and vertical sync signals, the monitor automatically resumes normal operation mode.
computer, it reduces power consumption as follows:

Power Required Recovery
State u Power Indicator
Consumption Time

1 Normal Operation <110W Green on

2 Standby (1st mode) <15W approx. 3 sec. Yellow

3 Suspend (2nd mode) <15W approx. 3 sec. Yellow

4 Active-off (3rd mode) <8W approx. 10 sec. Amber

5 Power-off 0W Off
--2--

6 Failure mode Orange flashing

TIMING SPECIFICATION

MODE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Resolution (H x V) 640x350 640X480 640x480 640x480 720x400 800x600 800x600 800x600 832x624 1024x768 1024x768 1024x768 1152x870 1280x1024 1280x1024
Dot Clock (MHz) 25.175 25.175 31.500 36.000 28.321 40.000 49.500 56.250 57.283 65.000 78.750 94.500 100.000 108.000 135.000

HORIZONTAL
Hor. Freq. (kHz) 31.469 31.469 37.500 43.269 31.468 37.879 46.875 53.674 49.725 48.363 60.023 68.677 68.681 63.981 79.976
H-Total 31.778 31.778 26.667 23.111 31.779 26.400 21.333 18.631 20.111 20.677 16.660 14.561 14.560 15.630 12.504
H-Blanking 6.356 6.356 6.349 5.333 6.356 6.400 5.172 4.409 5.586 4.923 3.657 3.725 3.040 3.778 3.022
H-Front Porch 0.636 0.636 0.508 1.556 0.636 1.000 0.323 0.569 0.559 0.369 0.203 0.508 0.320 0.444 0.119
H-Sync. 3.813 3.813 2.032 1.556 3.813 3.200 1.616 1.138 1.117 2.092 1.219 1.016 1.280 1.037 1.067
H-Back Porch 1.907 1.907 3.810 2.222 1.907 2.200 3.232 2.702 3.910 2.462 2.235 2.201 1.440 2.296 1.837
H-Active (msec) 25.422 25.422 20.317 17.778 25.423 20.000 16.162 14.222 14.524 15.754 13.003 10.836 11.520 11.852 9.481

VERTICAL
Ver. Freq. (Hz) 70.086 59.940 75.000 85.008 70.084 60.317 75.000 85.061 74.550 60.004 75.029 84.997 75.062 60.020 75.025
V-Total 449 525 500 509 449 628 625 631 667 806 800 808 915 1066 1066
V- Blanking 99 45 20 29 49 28 25 31 43 38 32 40 45 42 42
V-Front Porch 38 10 1 1 12 1 1 1 1 3 1 1 3 1 1
V-Sync. 2 2 3 3 2 4 3 3 3 6 3 3 3 3 3
V- Back Porch 59 33 16 25 35 23 21 27 39 29 28 36 39 38 38
V-Active (lines) 350 480 480 480 400 600 600 600 624 768 768 768 870 1024 1024

SYNC.
Int(G) NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO
Ext(H/V)/Polarity YES +/- YES -/- YES -/- YES -/- YES -/+ YES +/+ YES +/+ YES +/+ YES -/- YES -/- YES +/+ YES +/+ YES -/- YES +/+ YES +/+
Ext (CS)/Polarity NO NO NO NO NO 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 Non Int Non Int Non Int Non Int Non Int
P75
SAFETY CHECK-OUT
(US Model only)

After correcting the original service problem, perform LEAKAGE TEST
the following safety checks before releasing the set to the The AC leakage from any exposed metal part to earth ground
customer: and from all exposed metal parts to any exposed metal part having
a return to chassis, must not exceed 0.5 mA (500 microampere).
1. Check the area of your repair for unsoldered or Leakage current can be measured by any one of three methods.
poorly-soldered connections. Check the entire board
surface for solder splashes and bridges.
2. Check the interboard wiring to ensure that no wires 1. A commercial leakage tester, such as the Simpson 229 or
are "pinched" or contact high-wattage resistors. RCA WT-540A. Follow the manufacturers' instructions to
3. Check that all control knobs, shields, covers, ground use these instructions.
straps, and mounting hardware have been replaced. 2. A battery-operated AC milliammeter. The Data Precision
Be absolutely certain that you have replaced all the 245 digital multimeter is suitable for this job.
insulators. 3. Measuring the voltage drop across a resistor by means of
4. L o o k f o r u n a u t h o r i z e d re p l a c e m e n t p a r t s , a VOM or battery-operated AC voltmeter. The "limit"
particularly transistors, that were installed during indication is 0.75 V, so analog meters must have an accurate
a previous repair. Point them out to the customer low voltage scale. The Simpson's 250 and Sanwa
and recommend their replacement. SH-63Trd are examples of passive VOMs that are suitable.
5. Look for parts which, though functioning, show Nearly all battery operated digital multimeters that have a
obvious signs of deterioration. Point them out to 2V AC range are suitable. (See Fig. A)
the customer and recommend their replacement.
6. Check the line cords for cracks and abrasion. WARNING!!
Recommend the replacement of any such line cord
NEVER TURN ON THE POWER IN A CONDITION IN WHICH THE
to the customer.
DEGAUSS COIL HAS BEEN REMOVED.
7. Check the B+ and HV to see if they are specified
values. Make sure your instruments are accurate; SAFETY-RELATED COMPONENT WARNING!!
be suspicious of your HV meter if sets always have COMPONENTS IDENTIFIED BY SHADING AND MARK