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30
HCD-L7HD
SECTION 5
ELECTRICAL ADJUSTMENTS
CD SECTION
Note :
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M
Ω
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.
RF Level Check
Procedure :
1. Connect oscilloscope to TP (RFAC).
2. Turned Power switch on.
3. Load a disc (YEDS-18) and playback the number five track.
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
E-F Balance (1 Track jump) Check
Procedure:
1.
Connect oscilloscope to TP (TE) and TP (DVC) board.
2.
Turned Power switch on.
3.
Load a disc (YEDS-18) and playback the number five track.
4.
Press the
u
(CD) button. (Becomes the 1track jump mode.)
5.
Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.
1 track jump waveform
TP(RFAC)
TP(DVC)
BD board
oscilloscope
oscilloscope
BD board
TP (TE)
TP (DVC)
+
–
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.1
±
0.3Vp-p
A
B
0V
Center of
waveform
B
Symmetry
A (DC voltage)
level=1.3
±
0.6Vp-p
Adjustment Location :
[ BD BOARD ] – SIDE A –
IC103
TP
(RFAC)
TP(TE)
TP(DVC)
IC101
Specification level:
x
100=less than
±
22%
Summary of Contents for HCD-L7HD
Page 39: ...39 39 HCD L7HD 6 7 Schematic Diagram MOTOR Section ...
Page 42: ...42 42 HCD L7HD 6 10 Schematic Diagram HDD1 Section 1 2 See page 62 for Wavefoms ...
Page 46: ...46 46 HCD L7HD 6 14 Schematic Diagram HDD2 Section 2 2 FOR MEMORY STICK NOT USED ...
Page 49: ...49 49 HCD L7HD 6 17 Schematic Diagram MAIN Section 1 2 See page 62 for Wavefoms ...
Page 55: ...55 55 HCD L7HD 6 23 Schematic Diagram AMP Section See page 62 for Wavefoms ...
Page 57: ...57 57 HCD L7HD 6 25 Schematic Diagram DISPLAY Section See page 62 for Wavefoms ...
Page 59: ...59 59 HCD L7HD 6 27 Schematic Diagram CONTROL Section See page 62 for IC Block Diagrams ...
Page 61: ...61 61 HCD L7HD 6 29 Schematic Diagram POWER Section ...
Page 95: ...95 HCD L7HD MEMO ...