Philips 20MC4206/37, Руководство по обслуживанию

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1-6-1 T8201EA
ELECTRICAL ADJUSTMENT INSTRUCTIONS
General Note:
"CBA" is abbreviation for "Circuit Board
Assembly."
NOTE:
Electrical adjustments are required after replacing
circuit components and certain mechanical parts.
It is important to perform these adjustments only
after all repairs and replacements have been com-
pleted.
Also, do not attempt these adjustments unless the
proper equipment is available.
Test Equipment Required
1. NTSC Pattern Generator (Color Bar W/White Win-
dow, Red Color, Dot Pattern, Gray Scale, Mono-
scope, Multi-Burst)
2. AC Milli Voltmeter (RMS)
3. DC Voltmeter
4. Oscilloscope: Dual-trace with 10:1 probe,
V-Range: 0.001~50V/Div,
F-Range: DC~AC-60MHz
5. Frequency Counter
6. Plastic Tip Driver
7. Color Analyzer
How to make service remote control
unit:
1. Prepare remote control unit (Part No. NE241UD).
Remove 4 screws from the back lid. (Fig. 1)
2. Cut off pin 10 of the remote control microprocessor
and short circuit pins 10 and 17 of the microproces-
sor with a jumper wire.
How to enter the Service mode:
Service mode:
1. Use the service remote control unit.
2. Turn the power on.
3. Press "DISC MENU" button on the service remote
control unit.
- "**h" ("**" differs depending on the models) is
indicated on the lower right of the screen.
1. DC 105V (+B) Adjustment
Purpose: To obtain correct operation.
Symptom of Misadjustment: The picture is dark and
unit does not operate correctly.
Note:
J1124 (+B), VR1601 --- Main CBA
1. Connect the unit to AC Power Outlet.
2. Connect DC Volt Meter to J1124 (+B) and GND.
3. Adjust VR1601 so that the voltage of J1124 (+B)
b105
±
0.5V DC.
SCREW
Fig. 1
Remote control unit (Bottom)
Test point Adj. Point Mode Input
J1124(+B)
GND
VR1601 --- -----
Tape M. EQ. Spec.
---
DC Voltmeter
Plastic Tip Driver
+105
±
0.5V DC