Lcd System Adjustment; D Range Adjustment; Bright Adjustment (Pk-46 Board) - Sony MVC-FD73 Service Manual

1-4.

LCD SYSTEM ADJUSTMENT

1. D RANGE adjustment (PK-46 board)
(See original service manual page 5-20.)
: Changed point
This adjustment sets correctly the D range of LCD driver.
If disordered, LCD screen will blur or white blur.
Mode Playback
Signal Alignment disk: Stair-step signal of 10
steps
CN802 9 pin (VG)
Measurement point
External trigger: CN802 7 pin (HSY)
Measuring equipment Oscilloscope
Adjustment page F
Adjustment address 38
A=3.99 ± 0.05 Vp-p (SHARP)
Specification value
A=2.98 ± 0.05 Vp-p (CASIO)
Adjustment procedure:
1) Set data: 01 to page: 0, address: 01.
2) Change the data on page: F, address: 38 so that the voltage (A)
between pedestal of inverted waveform and pedestal of
noninverted waveform satisfies the specification value.
3) Press the PAUSE button on the adjustment remote commander.
Processing after adjustment finished:
1) Set data: 00 to page: 0, address: 01.
A
0 IRE
A: Pedestal level difference between 1H period and
previous 1H period.
Fig. 5-1-5
0 IRE
2H

2. BRIGHT adjustment (PK-46 board)

This adjustment sets correctly the VIDEO signal level that drives
the LCD. If disordered, LCD screen will not be sharp, or will white
blur or black blur.
(See original service manual page 5-20.)
: Changed point
Mode
Signal
Measurement point
Measuring equipment
Adjustment page
Adjustment address
Specification value
Adjustment procedure:
1) Set data: 01 to page: 0, address: 01.
2) Set data: 08 to page: 3, address: 18, and press the PAUSE button
on the adjustment remote commander.
3) Change the data on page: F, address: 30 so that the voltage (A)
satisfies the specification value. (Confirm that the data at
address: 30 is more than "41", and less than "BF".)
4) Press the PAUSE button on the adjustment remote commander.
Processing after adjustment finished:
1) Set data: 00 to page: 3, address: 18, and press the PAUSE button
on the adjustment remote commander.
2) Set data: 00 to page: 0, address: 01.
A
5-7
Playback
Alignment disk: Stair-step signal of 10
steps
CN802 9 pin (VG)
External trigger: CN802 7 pin (HSY)
Oscilloscope
F
30
A=1.78 ± 0.05 Vp-p (SHARP)
A=1.34 ± 0.05 Vp-p (CASIO)
0 IRE
2H
Fig. 5-1-6