Sony HCD-BC250 - AUTO SERVO ADJUSTMENT; RFMON Level Check

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HCD-BC150/BC250
SECTION 2
ELECTRICAL ADJSTMENT
DVD SECTION
AUTO SERVO ADJUSTMENT
After parts related to the servo circuit (RF amplifier (IC001), DSP
(IC509), motor driver (IC501), EEPROM (IC903) so on) are
replaced, re-adjusting the servo circuit is necessary. Select “ALL”
at “1. DRIVE AUTO ADJUSTMENT” (Refer to page 4 in TEST
MODE) and adjust DVD-SL (single layer), CD and DVD-DL (dual
layer).
[TEST DISC LIST]
Use the following test disc on test mode.
TDV-520CSO (DVD-SL): PART No. J-2501-236-A
LUV-P01 (CD): PART No. 4-999-032-01
TDV-540C (DVD-DL): PART No. J-2501-235-A
Note: Do not use exiting test disc for DVD.
[RFMON Level Check]
Connection:
+
–
DMB07 board
oscilloscope
CN901 pin 1 (RF)
CN901 pin
3 (GND)
Procedure:
1. Connect an oscilloscope to CN901 pin 1 (RF) and CN901
pin 3 (GND) on the SUB board.
2. Turn the power on.
3. Set the test disc (DVD: TDV-520CSO, CD: LUV-P01) on the
tray and press H button to playback.
4. Confirm that oscilloscope waveform is clear and check
RFMON signal level is correct or not.
Note: A clear RFMON signal waveform means that the shape “◊” can be
clearly distinguished at the center of the waveform.
RFMON signal waveform
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
level: 1.09
± 0.2 Vp-p (DVD)
1.05
± 0.2 Vp-p (CD)
Checking Location: DMB07 board (Side A)
IC801
IC207
IC901
IC509
IC701
CN501
CN901
CN901 pin 3 (GND)CN901 pin 1 (RF)
DMB07 BOARD
(Side A)