Frequency Check - Sony TRINITRON KV-20S90 Service Manual

V. FREQUENCY CHECK
1. Select video 1 with no signal input.
2. Set the conditions for a standard setting.
3. Connect the frequency counter to TP-508 or CN501 pin 6 (V DY+)
connector and ground.
4. Check that V. Frequency shows 60 ± 4 Hz.
SUB CONTRAST ADJUSTMENT (RDRV)
1. Input a color-bar signal.
2. Set the red color on (1).
3. Set in Service Adjustment Mode.
4. Select the item DCOL level to 0.
5. Set the conditions as follows:
PICTURE: MAX
COLOR: MIN
BRIGHT: CENTER
R ON: ON (1)
G ON: OFF (0)
B ON: OFF (0)
Mode
SERVICE
6. Connect an oscilloscope probe to CN301 pin 2 (Red Out) and
ground .
7. Select RDRV with 1 and 4 .
8. Adjust the value of RDRV with 3 and 6 for
1.50 ± 0.05 Vpp.
9. Reset the item DCOL to 1.
10. Press MUTING then ENTER to save into the memory.
11. Return the following back to normal after adjustment.
PICTURE: MAX
COLOR: CENTER
BRIGHT: CENTER
R ON: ON (1)
G ON: OFF (1)
B ON: OFF (1)
Display
1: ON
Item
0: OFF
RON 26
White
1.50 ± 0.05 Vpp
Black
DISPLAY POSITION ADJUSTMENT (DISP)
1. Input a color-bar signal.
2. Set to Service Adjustment Mode.
3. Select DISP with 1 and 4 .
4. Adjust values of DISP with 3 and 6 to adjust characters to the center.
5. Write to memory by pressing MUTING then ENTER .
6. Check to see if the text is displayed on the screen.
Mode
SERVICE
SUB BRIGHT ADJUSTMENT (SBRT)
1. Input a crosshatch signal.
2. Set to Service Adjustment Mode.
3. Set the PICTURE and BRIGHTNESS to minimum.
4. Select the SBRT item with 1 and 4 .
5. Adjust the values of SBRT with 3 and 6 to obtain a faintly visible
crosshatch.
6. Press MUTING then ENTER to save into the memory.
SUB HUE, SUB COLOR ADJUSTMENT (SHUE,
SCOL)
1. Input a color-bar signal.
2. Set to Service Adjustment Mode.
3. Connect a probe to TP47B B-OUT (C Board).
4. Measure white V1 and blue V4.
4.1) Increase SCOL Register +1 setp.
STANDARD
|V4 - V1| = ± 0.2Vpp
|V3 - V2| = ± 0.2Vpp
5. Press MUTING then ENTER to save into the memory.
— 19 —
KV-20S90 / 21SE43C
Display Item
Data
Item
DISP 15
V2 V3
V1 V4