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SECTION 4
SAFETY RELATED ADJUSTMENTS
4-4. +B OVP CONFIRMATION
1. Remove CN651 connector.
2. Connect a voltmeter to TP135V, and TP (PROT) and ground.
3. Connect a 220kΩ variable resistor, across pin 3 and pin 5
of IC651 set to maximum value.
4. Supply 220VAC to variable autotransformer.
5. Set PICTURE and the BRIGHTNESS controls to minimum.
6. Gradually turn the 220kΩ variable resistor, and check if OVP
works properly when the voltage of TP135V is between
139.0 ~ 151.5V. (Fig.4-2)