Sub Colour And Sub Brightness; Focus - Sony TRINITRON KV-20WS1A Service Manual

KV-20WS1
3-3. SCREEN (G2), DRIVE, WHITE BALANCE,

SUB COLOUR and SUB BRIGHTNESS.

Screen (G2) setting
1. Input a 0 IRE (Black Level) signal from the pattern
generator.
2. Enter into the Service Mode "Test""Test" and 38.
3. Adjust the SCREEN VR until the Down arrow is displayed.
4. Adjust the SCREEN VR until the Down arrow just disappears.
5. Press the TV Button on the Remote Commander to store
the data.
Drive Level
1. Input a Video signal containing a small area of 100%
white on a black background.
2. Connect an oscilloscope to Pin 7 of J701 (R OUT)
on the C Board.
3. Set the Picture to maximum using "Test""Test" and 01.
4. Enter into the Service mode (Adjust Menu).
5. Using the Blue and Green buttons select "RED HWB".
6. Using the Red and Yellow buttons on the Remote Commander
adjust until the oscilloscope waveform has
an amplitude of 85V.
White Balance Adjustment
1. Input an all white pattern from the pattern generator.
2. Adjust the Colour and Brightness controls to the standard
level.
3. Enter into the Service Mode.
4. Adjust the Green HWB and Blue HWB so that the
White Balance becomes optimum.
SCREEN
85V
— 18 —
Sub Colour Adjustment
1. Input a PAL colour bar pattern from the pattern generator.
2. Connect an oscilloscope to Pin 3 of J701 (B OUT)
on the C Board.
3. Enter into the Service Mode "Test""Test" and 22.
4. Using the Red and Yellow buttons on the Remote
Commander adjust until the oscilloscope waveform
becomes as follows :
B. OUT
.
Note : If the TV is able to receive PAL and SECAM
transmissions, repeat the above procedure using a Secam
colour bar signal.
Sub Brightness Adjustment
1. Input a Philips pattern from the pattern generator.
2. Enter into the Service Mode "Test""Test" and 23.
3. Using the Red and Yellow buttons on the Remote
Commander adjust until the 0 IRE of the grey scale and the
cut off are only slightly visible on the screen.

3-4. FOCUS

1. Receive a television broadcast.
2. Normalize the picture setting.
3. Adjust the focus control on the flyback transformer to
focus the screen centre area properly.
Bring only the centre area of the screen into focus, the
magenta-ring appears on the screen. In this case, adjust the
focus to optimize the screen uniformly.
SAME LEVEL
Focus