akira CT-14XA9A, Service Manual

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13
Model No: CT-14XA9A
Version 1.0
3. White Balance Adjustment
Generally, white balance adjustment is made with professional equipment. It's not practical to get good
white balance only through manual adjustment. For TVs with I2C bus control, change the bus data to
adjust white balance.
Circuit Adjustments
Preparation:
Circuit adjustments should be made only after completion of set-up adjustments.
Circuit adjustments can be performed using the adjustable components inside the TV set. For TVs with
I
2
C bus control, first change the bus data.
1. Degaussing
A degaussing coil is built inside the TV set. Each time the TV is powered on, the degaussing coil
will automatically degauss the TV. If the TV is magnetized by external strong magnetic field,
causing color spot on the screen, use a specific degausser to demagnetize the TV in the
following ways. Otherwise, color distortion will exist on the screen.
1.1
Power on the TV set and operate it for at least 15 minutes.
1.2 Receive red full-field pattern.
1.3 Power on the specific degausser and face it to the TV screen.
1.4 Turn on the degausser. Slowly move it around the screen and slowly take it away from
the TV.
1.5 Repeat the above steps until the TV is degaussed completely.
2. Supply Voltage Adjustment
Caution: +B voltage has close relation to high voltage. To prevent X-ray radiation, set +B voltage
to the rated voltage.
2.1 Make sure that the supply voltage is within the range of the rated Value.
2.2 Connect a digital voltmeter to the +B voltage output terminal of the TV set. Power on
the TV and set the brightness and sub-brightness to minimum.
2.3 Regulate voltage adjustment components on the power PCB to make the voltmeter read
115+-IV.
3. High Voltage Inspection
Caution: No high voltage adjustment components inside the chassis. Please perform high voltage
inspection in the following ways.
3.1 Connect a precise static high voltmeter to the second anode (inside the high voltage
cap) of the picture tube.
3.2 Plug in the supply socket (220V, AC) and turn on the TV. Set the brightness and
contrast to minimum.
3.3 The high voltage reading should be less than the maximum EHT voltage permissible.
3.4 Change the brightness from minimum to maximum, and ensure high voltage not
beyond the limitation in any case.
Nominal EHT voltage: 26.5+0.8KV Maximum EHT voltage permissible: 29KV