SONY MDP-V10
Manual de Servicio

MDP-V10 SECTION 8 EVALUATION OF OPTICAL PICK-UP BLOCK (KHS-150A)
� To evaluate whether the optical pick-up block (KHS-150A) is good or not good, perform as follows.

8-4. CROSSTALK CHECK
1. Play the CAV of the LD reference disc (HLV-8) to check the crosstalk at 770 frames. (For details, see 7-3-1. LD Side A Adjustment on page 7-4.) 2. Adjust the RV701 and RV702 on the MB-97 board so that the crosstalk becomes best condition (no moire observed). 3. At this time, if the RV701 and RV702 rotated more than the angle shown in Fig. 8-1 (normally, the rotation angle is within ±45º from the center), the suspension (spring) of pick-up will be deformed. Playing the LD under this condition could cause the images to be disturbed in the vicinity of outside. Replace the optical pick-up.

8-1. PREPARATION
Connect the jig (J-6082-059-B) to the CN702 on the MB-97 board. (For details of connection, see Fig. 7-1 on page 7-2, and for the jig, see Fig. 7-9 on page 7-4.)

8-2. RF LEVEL CHECK
Connect an oscilloscope to the LD RF terminal of jig. Load the CD test disc (YEDS-18). Press the · button to activate the play mode. At this time, check if the RF waveform level is over 0.7V. When the RF waveform level is over 0.7V, go to �8-3. Tracking Level/Tracking Balance Check�. 6. If the RF waveform level is below 0.7V, clean the lens using the lens cleaning kit. 7. After drying the lens completely, again check the RF waveform level. And if the RF level is still low, the laser diode in the optical pick-up block has deteriorated, or internal lens is dirty. Replace the optical pick-up block. 1. 2. 3. 4. 5.

Center

Within 45�

8-3. TRACKING LEVEL/TRACKING BALANCE CHECK
1. Connect an oscilloscope to the TRK ERR Y terminal of jig. 2. Unload the CD test disc (YEDS-18), and load the LD reference disc (HLV-8) instead. 3. Press the · button to activate the play mode, and play the chapter 3. 4. After playing, please the set in the still status. At this time, observe the tracking error waveform on the oscilloscope to check that both level and balance satisfy the specification given below. Specification Level: 3V or more Balance: �6% to +9% Note: For a calculation method of balance, see Fig. 7-8 on page 74.

Within 45�

Fig. 8-1.
Notes: � In executing the above operation, if no signal is output from each terminal of jig, the laser diode will be deteriorated. When red beam is not generated from the lens during the focus search, replace the optical pick-up block. � The above checking uses basically the reference disc, and if no particular abnormality is found, a failure which occurs in the user�s disc only may be present. Especially, in the case of LD, if a wavy tracking error as shown in Fig. 8-2 appears, the pick-up is resonating. Replace it with a new one.

Tracking Error (Y)

Fig. 8-2. Play Mode

8-1 E 8-1