Picture Adjustments - Sharp 28JF-76E Service Manual

Colour Adjustments
The following adjustments should only be carried out when the CRT or IC850, IC851 and IC852 are replaced.
Follow the procedure below to set the Cut Off.
Do not change the Cut RED value (50%).
1. Adjust G2.
2. Tune a white pattern.
3. Adjust colour to minimum.
4. Position colorimeter in the centre of screen.
5. Adjust brightness and contrast to obtain a luminance of »20 NITS.
6.Operate in Service Mode and select location GREEN CUT OFF and BLUE CUT OFF, to obtain colour
coordinates:
X=0.290 ± 0.015
X=0.304 ± 0.015
To increase press volume-up button and to decrease press volume down button.
BLUE CUT OFF
GREEN CUT OFF
Press the Store button of Remote Control to store all values.
Follow the procedure below to adjust the customer Colour Limit Control (Hot / Cold).
1. Tune a white pattern.
2. Adjust colour to minimum.
3. Position colorimeter in the centre of screen.
4. Adjust brightness and contrast to obtain a luminance of »20 NITS.
5. Operate in Service Mode and select location "Hot Cut RED", "Hot Cut GREEN" and "Hot Cut BLUE" by
channel up/down buttons of the Remote Control.
6. Press volume up/down to adjust "Hot Cut RED", "Hot Cut GREEN" and "Hot Cut BLUE" to obtain the colour
limit coordinates (X/Y) for HOT picture variation.
7. Select location "Cold Cut RED", "Cold Cut GREEN" and "Cold Cut BLUE" by channel up/down buttons of the
Remote Control.
8. Press volume up/down to adjust "Cold Cut RED", "Cold Cut GREEN" and "Cold Cut BLUE" to obtain the
colour limit coordinates (X/Y) for COLD picture variation.
9. Press the Store button of Remote Control to store all adjustments.
10. Turn off the receiver by Main switch to exit the Service Mode.

Picture Adjustments

Automatic Gain Control Adjustment (B/G, D/K)
To correctly align the Automatic Gain Control, follow the procedure outlined below:
1. Tune the set into a pattern generator on E-12.
2. Enter the Service Mode.
3. Press the YELLOW button of Remote Control to select "Automatic Gain Control"
4. Press volume up/down to adjust to "109 dB/µV".
5. It will be stored automatically.
6. Turn off the receiver by Main switch to exit the Service Mode.
Automatic Gain Control Adjustment (I)
To correctly align the Automatic Gain Control, follow the procedure outlined below:
1. Tune the set into a pattern generator on I-21.
2. Enter the Service Mode.
3. Press the YELLOW button of Remote Control to select "Automatic Gain Control"
Y=0.300 ± 0.015
Y=0.306 ± 0.015 (ONLY FOR 28JF-76E)
alter «X» e «Y» coordinates.
alter «Y» coordinate.
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28JF-76E