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The following adjustments should only be carried out when the CRT, IC850, IC851
or IC852 are replaced.

1.1 Tune the set to the output of a signal generator (cross hatch pattern).
1.2 2. In the user menu, set the picture levels to the FACTORY  settings
         (normalized).
1.3 Connect the oscilloscope to the RED cathode (pin 8 of CRT socket)
      and adjust G2 to read 150V on the sensor pulse as in the drawing:

Note: Oscilloscope should be adjusted for vertical TV field trigger and synchronized with
          video signal.

Adjust the Vertical Bow so that the picture is centred.
The effect of this adjustment is shown in figure 11.

• 

When the volume up button is pressed, the vertical bow changes to left.

• 

When the volume down button is pressed, the vertical bow changes to right.

• 

Press the stand-by button on the remote control to store.

Adjust the Vertical Amplitude so that 8% over-scan is achieved.
The effect of this adjustment is shown in figure 12.

• 

When the volume up button is pressed, the vertical size of the picture increases.

• 

When the volume down button is pressed, the vertical size of the picture decreases.

• 

Press the stand-by button on the remote control to store.

Adjust the S Correction so that the picture symmetrical between the top, centre and bottom.
The effect of this adjustment is shown in figure 13.

• 

When the volume up button is pressed, the top and bottom scanning decreases and the

centre scanning increases.

• 

When the volume down button is pressed the top and bottom scanning increases and the

centre scanning decreases.

• 

Press the stand-by button on the remote control to store.

Adjust the Vertical Shift so that the picture is centred.
The effect of this adjustment is shown in figure 14.

• 

When the volume up button is pressed, the picture moves up.

• 

When the volume down button is pressed, the picture moves down.

• 

Press the stand-by button on the remote control to store.

Figure 14

Figure 11

Figure 12

Figure 13

CH1 gnd

Figure 15

2.1 Adjust G2.
2.2 Tune a white pattern.
2.3 Adjust colour to minimum.
2.4 Position colorimeter in the centre of screen.
2.5 Adjust brightness and contrast to obtain a luminance of 

≈20 

NITS.

2.6 Operate in Service Mode and select location RED CUT OFF, GREEN CUT OFF and  BLUE CUT OFF, to

obtain colour coordinates:

X=0.290 ± 0.015       Y=0.284 ± 0.015

To increase press volume-up button and to decrease press volume down button.

RED CUT OFF

 alter «X» coordinate.

GREEN CUT OFF  alter «Y» coordinate.
BLUE CUT OFF

 alter «X» and «Y» coordinate.

They will be stored automatically.

In case that the required equipment (Colorimeter / 

oscilloscope) is

 not available, please follow the procedures below to

obtain correct G2 and Grey scale settings (R-G-B Cut Off).

Follow the procedure below to set the G2:

1. Tune the set to the output of a signal generator (Cross-hatch pattern).
2. In the user menu, set the picture levels to the FACTORY  settings (normalized).
3. Connect a DC voltimeter at the Red amplifier output  (Pin 9 IC850) and adjust G2 to read 145V

DC (

±

5V).

Do not change the Cut RED value (50%).

1. Adjust G2.
2. Tune a grey scale pattern.
3. Adjust colour to minimum.
4. Operate in Service Mode and select location GREEN CUT OFF and  BLUE CUT OFF.
5. Adjust these parameters until achieve a correct grey scale tracking.

To increase press volume-up button and to decrease press volume down button.
Press the Store button of Remote Control to store all values.

To change the data contained within the Non Volatile Memory, it is necessary to first select the page the data is stored in,
then the position and finally to change the data itself.  The procedure below outlines this process.

1. While on ALTER NVM PAGE, use the volume up/down buttons to change this data (it is shown in hexadecimal format).
2. Press the channel up button and ALTER NVM POSITION appears, use the volume up/down buttons to change this

data (it is shown in hexadecimal format).

3. Press the channel up button and ALTER NVM VALUE appears, use the volume up/down buttons to change this data

(data is shown in hexadecimal format).

4. Once this data has been set, press the stand-by button to store.
5. If another NVM value has to be changed, use the channel down button to select the page or position and repeat as

necessary.

Note:
DO NOT change any NVM data, unless you have been advised to do so by a Sharp representative.  If data is incorrectly
changed, serious damage may occur to the receiver.

Three types of contrast levels can be varied as listed below:

• 

TELETEXT MIX MODE CONTRAST

• 

TELETEXT CONTRAST

• 

OSD CONTRAST

Carry out the DVCO Adjustment (NTSC) as shown below:

To correctly align the Automatic Gain Control, follow the procedure outlined below:

In order to reset the PostCode when password is not on mind, enter and exit the Service Mode.

4. Once this data has been set, press the stand-by button to store.
5. If another NVM value has to be changed, use the channel down button to select the page or position and repeat as

necessary.

Note:
DO NOT change any NVM data, unless you have been advised to do so by a Sharp representative.  If data is incorrectly
changed, serious damage may occur to the receiver.

Three types of contrast levels can be varied as listed below:

• 

TELETEXT MIX MODE CONTRAST

• 

TELETEXT CONTRAST

• 

OSD CONTRAST

Carry out the DVCO Adjustment (NTSC) as shown below:

To correctly align the Automatic Gain Control, follow the procedure outlined below:

In order to reset the PostCode when password is not on mind, enter and exit the Service Mode.