Sony DVP-NS300 Training Manual page 26

Testing - Tracking Servo Checks
Table 5-1 lists the ICs responsible for track jump and basic servo operation.
Device
RF Amp IC201
Servo IC302
Driver IC202
Tracing coil (Optics)
System Control
(Syscon) IC104
EEPROM IC101
HGA IC403
Testing -Checking the TE signal:
This check is only possible in service mode.
1. On the remote press buttons: Title, clear, then Power.
2. A SL test disc must be inserted.
3. Switch ON the "Drive Manual Operation" (2).
4. Next switch to "Disc Type" (1). Now check the inserted disc Type, select "Disc Type Auto Check" (1). The
detected disc type is shown on th bottom of the screen; it should be "DVD SL 12 cm.
5. Push "RETURN" and select "Servo Control" (2).
6. Start PB by switching "LD ON" (1), "SP ON" (2) and "Focus ON" (3). [See Figure 5-8]
7. The measured traverse TE signal level is aproximately 1,6 Vpp. The DC-Level in relation to „VC" is around
780 mV.
FIGURE 4-8 - SERVO CONTROL TV SCREEN IN DVD SERVICE MODE
Table 5-1 - Tracking IC Responsibilities
Servo Track
Jump
Yes
Yes Yes
Yes Yes
Yes Yes
Yes
Yes
Yes
24
Purpose
Creates TE voltage
Sets tracking position
Voltage to current driver
Corrects lens position
Determines when to jump (look for another
location)
Stores previous / future jump location.
Expansion port for Syscon IC104
5. Testing