Cd Section - Sony CX-LEM550 Service Manual

CX-LEM550
3. Mode: Playback
MAIN board
SPEAKER terminal (J302)
test tape
L-CH
P-4-A100
(10 kHz, – 10 dB)
L-CH
set
R-CH
R-CH
waveform of oscilloscope
in phase 45 °
good
4. After the adjustments, apply suitable locking compound to
the parts adjusted.
Adjustment Location:Record/Playback/Erase Head
Tape Speed Check
Mode: Playback
test tape
WS-48B
(3 kHz, 0 dB)
set
MAIN board
SPEAKER terminal (J302)
L-CH, R-CH
1. Turn the power on.
1. Insert the WS-48B into the deck.
2. Press the nN button on the deck.
3. Confirm that the frequency counter reads 3,000 ± 90 Hz.
Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)

CD SECTION

Note:
1. CD Block is basically constructed to operate without
adjustment.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10 MΩ impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
5. Check the focus bias check when optical block is replaced.
14
oscilloscope
V H
90 ° 135 ° 180 °
wrong
frequency counter
+
–
(WS-48B)
FOCUS BIAS CHECK
CD board
TP (RFACO)
TP (VC)
Procedure :
1. Connect the oscilloscope to TP (RFACO) and TP (VC) on the
CD board.
2. Insert the disc (YEDS-18). (Part No. : 3-702-101-01)
3. Press the [CD ] button.
NX
4. Confirm that the oscilloscope waveform is as shown in the
figure below. (eye pattern)
A good eye pattern means that the diamond shape (◊) in the
center of the waveform can be clearly distinguished.
• RF signal reference waveform (eye pattern)
VOLT/DIV: 0.2 V (with the 10: 1 probe in use.)
TIME/DIV: 500 ns
When observing the eye pattern, set the oscilloscope
for AC range and raise vertical sensitivity.
Checking Location:
– CD BOARD (Conductor Side) –
TP (VC)
oscilloscope
(DC range)
+
–
1.1
0.2 Vp-p
TP
(RFACO)