Back Light Adjustment (Pk-65/66 Board); Vco Adjustment (Pk-65/66 Board) - Sony MVC-CD250 Service Manual

3. Back Light Adjustment (PK-65/66 Board)

Set the backlight luminance and color temperature.
If deviated, the image may become dark or bright.
Mode PLAY
Signal Arbitrary
Measurement Point Pin qd of CN714 on SY-76 board
(BL DC)
Measuring Instrument Digital voltmeter
Adjustment Page A
Adjustment Address 80 (Normal)
81 (Bright)
Specified Value A = 4.00 ± 0.05 V (Normal)
A = 5.45 ± 0.05 V (Bright)
Adjusting method:
Order Page Address Data
1 0 01 01
2 A 02 03
3 A 80
4 A 80
5 A 81
6 A 81
Processing after Completing Adjustments:
Order Page Address Data
1 A 02 00
2 0 01 00
Procedure
Press PAUSE button.
Change the data and set the
voltage (A) to the normal
specified value.
Press PAUSE button.
Change the data and set the
voltage (A) to the bright
specified value.
Press PAUSE button.
Procedure
Press PAUSE button.

4. VCO Adjustment (PK-65/66 Board)

Set the VCO free-run frequency. If deviated, the LCD screen will
be blurred.
Mode
Signal
Measurement Point
Measuring Instrument
Adjustment Page
Adjustment Address
Specified Value
Menu setting:
1) VIDEO OUT of SET UP setting
......................... NTSC (NTSC mode)
(This adjustment must be performed in NTSC mode, so don't
set the menu setting to "PAL" )
Adjusting method:
Order Page Address Data
1 0 01
2 A 02
3 4 F1
4 A 82
5 A 82
6 4 1D
7 A 83
8 A 83
Processing after Completing Adjustments:
Order Page Address Data
1 A 02
2 4 F1
3 4 1D
4 0 01
5-39
MVC-CD250/CD400
PLAY
Arbitrary
Pin 7 of CN714 on SY-76 board
(HSY)
Frequency counter
A
82 (NTSC)
83 (PAL)
f = 15734 ± 30 Hz (NTSC)
f = 15625 ± 30 Hz (PAL)
Procedure
01
03 Press PAUSE button.
13
Change the data and set the
frequency (f) to the NTSC
specified value.
Press PAUSE button.
82
Change the data and set the
frequency (f) to the PAL
specified value.
Press PAUSE button.
Procedure
01 Press PAUSE button.
00
80
00