28
HCD-M10
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. Turn the power on.
3. Load a disc (YEDS-18) and playback.
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.
E-F Balance (1 Track jump) Check
Procedure:
1. Connect oscilloscope to TP (TE) and TP (DVC 1.65V).
2. Turn the power on.
3. Load a disc (YEDS-18) and playback the number five track.
4. Press the
u
button. (Becomes the 1track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.
Specification level:
x
100=less than
±
22%
TP(RFAC)
TP(DVC 1.65V)
CD BOARD
oscilloscope
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.1
±
0.3Vp-p
CD BOARD
Oscilloscope
TP(TE)
TP(DVC 1.65V)
0V
Center of
waveform
B
Symmetry
A (DC voltage)
B=1.3
±
0.6Vp-p
Record Level Check
Procedure:
1. Press FUNCTION button to select ANALOG IN.
2. Insert a tape into deck, press the
z
TAPE button, and then press
the
X
TAPE button to start recording.
3. Mode: Record
4. Mode: Playback
5. The playback output level should be –2
±
4 dBs (60 Hz),
–1
±
4 dBs (8 kHz) and –3
±
4 dBs (10 kHz) compared with 315Hz
playback level.
AF OSC
PJ301
ANALOG IN
1) 315 Hz
2) 60 Hz
3) 5 kHz
4) 10 kHz
blank tape
CS-123
set
attenuator
600
Ω
109 mV (–17 dB)
recorded
position
level meter
set
32
Ω
J301
PHONES
1.3
±
0.6Vp-p
A