Cd (Motor/ Sensor) Section; Connecting Points - Sony HCD-MD515 - Component For Dhcmd515 Service Manual

CD SECTION
Notes:
1. CD Block basically constructed to operated without adjust-
ment.
Therefore, check eaech item in order given.
2. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise
indicated.
3. Use the oscilloscope with more than 10 M impedance.
4. Clean an object lens by an applicator with neutral detergent
when the signal level is low than specified value with the fol-
lowing checks.
1. S-Curve CHECK
Connection:
oscilloscope
BD (CD) board
TP (FEO) +
TP (VC)
–
Procedure:
1. Connect the oscilloscope to TP (FEO) and TP (VC) on BD
(CD) board.
2. Connect the TP (FOK) and TP (GND) with lead wire.
3. Turned power switch on.
4. Put disc (YEDS-18) in and turned power switch on again and
actuate the focus search. (actuate the focus search when disc
table is moving in and out.)
5. Confirm that the oscilloscope waveform (S-curve) is symmetri-
cal between A and B. And confirm peak to peak level within
2.4 ± 0.7 Vp-p.
S-curve waveform
symmetry
A
within 2.4 ± 0.7 Vp-p
B
6. After check, remove the lead wire connected in step 2.
Note: • Try to measure several times to make sure that the ratio
of A : B or B : A is more than 10 : 7.
• Take sweep time as long as possible and light up the bright-
ness to obtain best waveform.
2. RF LEVEL CHECK
Connection:
oscilloscope
BD (CD) board
TP (RF) +
TP (VC)
–
Procedure:
1. Connect the oscilloscope to TP (RF) and TP (VC) on BD (CD)
board.
2. Turned power switch on. (stop mode)
3. Put disc (YEDS-18) in and press the ^ button.
4. Confirm that oscilloscope waveform is clear and check RF
signal level is correct or not.
Note: Clear RF signal waveform means that the shape "≈" can
be clearly distinguished at the center of the waveform.
RF signal waveform
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
(with the 10 : 1 probe
in use)
1.3 ± 0.3 Vp-p
3. E-F BALANCE (TRAVERSE) CHECK
Connection:
oscilloscope
(DC range)
BD (CD) board
TP (TEO) +
TP (VC)
–
Procedure:
1. Connect the lead wire to TP607. (on the SUB board)
2. Connect the oscilloscope to TP (TEO) and TP (VC) on BD
(CD) board.
3. Turned power switch on.
4. Select the CD function.
5. Connect the lead wire to ground (from TP607)
6. Put disc (YEDS-18) in and press the ^ button.
7. Press the DISPLAY button. (Tracking servo and sled servo
are turned off.)
8. Confirm that the oscilloscope waveform is symmetrical on the
top and bottom in relation to 0 Vdc, and check this level.
9. Release the lead wire.
– 29 –

4. CONNECTING POINTS

[BD (CD) BOARD] – Side B –
IC102
FOK
RF
IC101
FEO
IC103
TEO
VC
GND
[SUB BOARD] – Conductor Side –
IC500
IC600
CN600 CN601
TP607
– 30 –