B Max Voltage Confirmation; B Ovp Confirmation - Sony KP-XR432K90 Service Manual

5-3. +B MAX VOLTAGE CONFIRMATION

The following adjustments should always be performed when
replacing IC654.
1. Supply 130VAC to with variable autotransformer.
2. Input a dot signal.
3. Set the PICTURE control and the BRIGHTNESS controls to
minimum.
4. Confirm the voltage of G BOARD TP135V is less than
137.0Vdc.
5. If step 4 is not satisfied, replace IC654 and repeat above steps.

5-4. +B OVP CONFIRMATION

1. Connect an external dc power supply to TP OVP.
2. Supply 120VAC to variable autotransformer.
3. Set PICTURE and the BRIGHTNESS controls to minimum.
4. Gradually turn the external dc power supply, and check if
OVP works properly when the voltage of the external dc
power supply is between 139.0 ~ 155.0V.
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KP-XR432K90/XR432N90
RM-Y906K RM-Y906