Sony CD Walkman D-EJ2000, Руководство по обслуживанию

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D-EJ2000
SECTION 5
DIAGRAMS
Note on Printed Wiring Board
•
X
: parts extracted from the component side.
•
Y
: parts extracted from the conductor side.
• : Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
• MAIN board is multi-layer printed board. However, the pat-
terns of intermediate-layer have not been included in the dia-
gram.
Caution:
Pattern face side:
Parts on the pattern face side seen from
(Side B) the pattern face are indicated.
Parts face side: Parts on the parts face side seen from
(Side A) the parts face are indicated.
Note on Schematic Diagram:
• All capacitors are in
µ
F unless otherwise noted. pF:
µµ
F 50 WV or
less are not indicated except for electrolytics and tantalums.
• All resistors are in
Ω
and
1
/
4
W or less unless otherwise specified.
• % : indicates tolerance.
• C : panel designation.
• H : adjustment for repair.
• A : B+ Line.
• Total current is measured with CD installed.
• Power voltage is dc 3 V and fed with regulated dc power supply
from DC IN jack (J402).
• Voltages and waveforms are dc with respect to ground in playback
mode.
no mark : CD PLAY
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal production toler-
ances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal production toler-
ances.
• Circled numbers refer to waveforms.
• Signal path.
J : CD PLAY (ANALOG OUT)
c : CD PLAY (OPTICAL OUT)
NOTE FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS
• WAVEFORMS
490 mVp-p
1
IC601
if
RFAC
100mV/DIV, 400ns/DIV
2
IC601 rk XTAO
1V/DIV, 20ns/DIV
3
IC801
2
XIN
1V/DIV, 100ns/DIV
4
IC801
qk
MSCK-O
1V/DIV, 400ns/DIV
59ns 236ns 945ns
2.4 Vp-p
2.5 Vp-p 2 Vp-p
The CD section adjustments are done automatically in this set.
In case of operation check, confirm that RF level.
Precautions for Check
1. Perform check in the order given.
2. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise
indicated.
3. Power supply voltage requirement : DC3 V in DC IN jack.
(J402)
VOLUME button : Minimum
AVLS switch : NORM
HOLD switch : OFF
G-PROTECTION switch : 1
Checking Location:
– MAIN board (Side B) –
RF Level Check
Condition:
• Hold the set in horizontal state.
Connection:
Procedure:
1.
Connect the oscilloscope to the test points TP609 (RF) and
TP402 (GND) on the MAIN board.
2. Set a disc. (YEDS-18)
3. Press the u button.
4. Check the oscilloscope waveform is as shown below.
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 : 100 mV (With the 10:1 probe in use)
TIME/DIV : 500 ns
To watch the eye pattern, set the oscilloscope to AC range and
increase the vertical sensitivity of the oscilloscope for easy watch-
ing.
5. Stop revolving of the disc motor by pressing the
x
button.
Oscilloscope
(AC range)
+
–
MAIN board
TP609 (RF)
TP402 (GND)
2 k
Ω
RF level
0.34 to 0.74 Vp-p
TP402
(GND)
CN402
IC601
IC801
IC402
IC404
IC405
TP609
(RF)
CN603
The components identified by mark 0 or
dotted line with mark
0
are critical for safety.
Replace only with part number specified.