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DA100 (50Hz) Chassis – Article for Television Magazine 

Sharp Electronics (UK) Limited - March 2003 

All adjustments to this chassis, except for focus, are carried out in the service mode. 
The service mode is provided to enable the engineer to correctly set up the receiver to the CRT fitted 
in the set. Note that these adjustments may vary from one receiver to another. 

To enter the service mode, carry out the following procedure: 
 
1.  Connect a test pattern to the antenna terminal. 
2.  Tune the receiver to this signal. 
3.  Turn the receiver off using the mains switch.  
4.  Press volume down and channel up buttons on the front 

of the receiver at the same time. 

5.  Keeping these buttons pressed, turn the mains on. 
6.  When the set starts up it will be in service mode. 
7.  Release the two buttons. 
 
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Use the channel up and down buttons to move between the options. 

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Use the volume control buttons to change the data. 

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To store the data, use the stand-by button on the remote control. 

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To exit the service mode, turn the receiver off using the mains switch. 

 
When the service mode is entered the following On Screen Display appears 
 

 

The figures displayed in the XXXX locations are hexadecimal representations of the number of times 
that particular function has been executed. For example if the hexadecimal number displayed after 
SW ON was 0E4A, this would correspond to the receiver being turned on 3658 times. 
The following adjustments can be carried out in the service mode: 
 
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Horizontal Shift 

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East West Width 

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Pin Phase 

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Pin Amp 

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Corner Amplitude 

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Corner Symmetry 

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Vertical Linearity 

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Vertical Amplitude 

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S Correction 

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Vertical Shift 

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Red Gain 

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Green Gain 

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Blue Gain 

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Red Cut Off 

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Green Cut Off 

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Blue Cut Off 

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Alter NVM Page 

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Alter NVM Position 

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Alter NVM Value 

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Teletext Mix Mode Contrast 

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Teletext Contrast 

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OSD Contrast 

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DVCO Adjustment (NTSC) 

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DVCO Adjustment (PAL) 

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AGC Adjustment 

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AFT Adjustment 

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OPC Value 

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Auto Installation On/Off 

DA100 (50Hz) Chassis – Article for Television Magazine 

All geometry adjustments are based on an internally generated test pattern as shown below. When 
carrying out any of the above geometry adjustments, use the internally generated test pattern for 
guidance. 
 

 

Follow the procedure below to set the G2 and Grey scale: 
1.  Tune the set to the output of a RF signal generator. 
2.  In the user menu, set the picture levels to the FACTORY settings. 
3.  In the user menu, set the tint control to its central position. 
4.  Enter the test mode. 
5.  Set the ABL levels in the NVM by adjusting positions 60, 61, 62, 63, 64 and 65 on page 00 to read 

80. Store each location by pressing the standby button on the remote control. 

6.  When the ABL levels have been set, adjust the G2 and grey scale (if necessary) as below. 

After setting the ABL levels as above, go to the Red Cut Off adjustment. The following data will 
appear on the screen. 

  
Using a cross hatch pattern set the G2 control on the line output transformer so that the display in 
the Red cut off box reads between 60 and 80 as indicated above. 
Important 
After setting the G2 control, it is necessary to re-set at least one of the RGB adjustments to force 
the software to re-set the correct ABL levels.  Just adjust one of the grey-scale gain or drives by one 
point.  There is no need to press the standby button to store this adjustment. 

Sharp Electronics (UK) Limited - March 2003 

DA100 (50Hz) Chassis – Article for Television Magazine 

Sharp Electronics (UK) Limited - March 2003 

1.  Using a grey scale pattern set the Red Cut-off value to 32 and the Red Gain value to 50. 
2.  Leave the Red Cut Off and Gain as above and adjust Green and Blue Cut-off and Gain to achieve 

correct grey scale tracking. As with all grey scale adjustments it will be necessary to re-adjust 
the settings to achieve good tracking. 

Note 
When adjusting the grey scale, the figures displayed in the boxes are an indication of the CRT’s 
performance only. 
These adjustments are for guidance only. If any problems should be encountered the adjustments 
should be carried out using a Colorimeter as explained in the service manual. 
 

DA100 (50Hz) Chassis – Article for Television Magazine 

Sharp Electronics (UK) Limited - March 2003 

 
 

These tables are for guidance only