72GF-66E

ADJUSTMENT PROCEDURES

All adjustments to this chassis, except for focus, are carried out in the service mode.

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.

Use the channel up and down buttons to move between the options.

Use the volume control buttons to change the data.

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

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

-SERVICE SOFTWARE AND HEXADECIMAL COUNTER DISPLAY: SW ON XXXX SW OFF XXXX HOURS ON XXXX

CH

4

5

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.

Adjustment menu:

The following adjustments can be carried out in the service mode.

Horizontal Shift

Green Cut Off

East West Width

Blue Cut Off

Pin Phase

Alter NVM Page

Pin Amp

Alter NVM Position

Upper corner correction

Alter NVM Value

Lower corner correction

Teletext Mix Mode Contrast

Vertical Linearity

Teletext Contrast

Vertical angle

OSD Contrast

Vertical bow

DVCO Adjustment (Only PAL)

Vertical Amplitude

DVCO Adjustment (Only NTSC)

S Correction

Luma croma delay

Vertical Shift

AGC Adjustment

Red Gain

AFT Adjustment (BG-I-L)

Green Gain

AFT Adjustment (L’)

Blue Gain

OPC Value

Red Cut Off

Auto Installation On/Off

Geometry Adjustments

All geometry adjustments are based on an internally generated test pattern as shown in figure 1. When carrying out any of the above geometry adjustments, use the inter-

nally generated test pattern for guidance. Fig.1

5

Page 5
Image 5
Sharp 72GF-66E service manual Adjustment menu, Geometry Adjustments