Adjustment
A. Safety precautions
1. It is safe to adjust after using insulating transformer between the power supply line and
chassis input to prevent the risk of electric shock and protect the instrument.
2. Never disconnect leads while the TV receiver is on.
3. Don't short any portion of circuits while power is on.
4. The adjustment must be done by the correct appliances. But this is changeable in view of
productivity.
B. Adjustment procedure
The chassis of this TV set uses Philips single chip IC with the latest digital bus processing
technology. The adjustment points are fewer and the adjustment is simpler. The adjustment
method is as follows:
1. +B: 127
±
0.5V adjustment
1) Switch on the power and connect PAL circular signals to the modulator.
2) Turn the acceleration pole anti-clockwise fully. Adjust potentiometer VR701 until the
voltage of the main power is 127
±
0.5V.
2. Screen voltage adjustment
1) Switch on the power and receive PAL system circular signal. Warm up the TV set for 15
min.
2) Press factory handset SERVICE button to enter the adjustment status. Press MENU
button twice. After the screen displays MENU3, press button 0 and a horizontal bright
line appear. Adjust screen potentiometer to let the horizontal bright line just appears.
3. Focus adjustment
1) Receive electronic circular signal
2) Set contrast control to max.
3) Set brightness control to middle
4) Adjust focus potentiometer F1 and F2 until the optimum picture is achieved
4. AGC adjustment
1) Switch on the power and connect signals to the modulator. Receive PAL system color bar
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