Sharp SYSTEM-CD555ZT(GY) - CD Mechanism Exploded View

SYSTEM-CD55
Is
pin
17
of
CNP951
at
a
high
level?
Check
the
LCD
PWB
of
CD.
(Check
the
LD
ON
terminal
of
pin
9
of
C951.)
No
:
Is
there
+5
V
at
the
Q890
emitter?
No
Check
the
+5
V
line
of
pin
1
of
CNP881.
is
there
+5
V
at
the
Q890
collector?
Is
there
a
low
level
(+0.1
V)
between
Check
the
PWB
pattern
between
pin
17
N
pin
17
of
CNP951
and
R749?
No
of
CNP951
and
R749.
Yes
?
No
Check
between
pin
1 of
1C750
and
es
Is there +4.1 V at the Q890 base?
lo
Y Q890 base.
Q890 is defective.
Is
there
+5
V
at
pin
5
of
CFS700?
0
The
PWB
pattern
between
Q890
and
pin
5
of
CFS700
is
damaged.
Check the CFS700 and Flexible PWB. If they are normal, the pickup is defective.
Yes
Yes
Yes
: N
Yes
When
the
disc
is
removed,
is
the
pickup
Check
the
item
of
“The
saw-tooth
wave
for
focus
servo
does
not
output”.
moving
up and
down?
No
Yes
Is
the
focus
gain
adjusting
VR751
set
to
the
Readjust
the focus
gain.
minimum
position?
Yes
;
No
me
.
:
ls
a
waveform
output
at
pin
42
Is
a
waveform
output
at
pin
13
(MLA)
of
When
the
disc
is
set,
is the
following
fener
|
waveform input
to
pin
41
(FE
OUT)
of
C7502}
No
—
[(FE(+))
of
10750?
No
|
!C750?
Yes
|
[No
dyes
Yes
Rape
1C750
is
defective.
Check
the
flexible
|
Disconnection
of
PWB.
If
OK,
the chat
decane
Pin 37
ickup
is
defective.
(FsouT)
soles
ss
pattern
and
parts.
Is
the
waveform
shown
at
right
input
at
pin
7
The
pickup
is
defective.
(HFOK)
of IC750?
No
-
:
Pin
40
Yes
(FEOUT)
~
1C750 is defective Pin7 4V ‘
OCU Ce ee Ai,
Is there +5 V at pin 24 (Vcc) of C750? No The +5V line of IC750 is defective.
The PWB pattern is damaged.
Yes
7
5
:
Does
the
saw-tooth
wave
look
like
Check
the
C767
and
R779
(pins
22
monucar
No
|
the
following
waveform?
No
|
and
23
of
1C750).
OK,
IC780
is
defective.
qokes Yes. (The saw-tooth wave oscillates
to the positive side once.) he ae
Yes ee Bs V/
SPINES.
Check
the
peripheral
circuits
of
pin
36
(FSR
IN).
of
IC750.
If
OK,
1C750
is
defective.
-
ls
the
saw-tooth
wave
being
input
to
pin
8
of
IC700
(same
The
signal
line
between
pin
35
(FSOUT)
of
IC750
and
pin
8
of
IC700
is
waveform
as
shown
above)?
No
connected
improperly.
Yes
is
the
saw-tooth
wave
generating
between
pins
3
and
6
of
Check
the
peripheral
parts
of
C700
and
the
power
line.
If
OK,
IC700
is
1C700
(same
waveform
as
shown
above)?
No
defective.
i
Yes
Is
the
saw-footh
wave
generating
between
pins
2
and
3
The
CFS700
and
flexible
PWB
are
connected
improperly
or
the
pickup
is
of CFS700 (same waveform as shown above)? Yes | defective.
No ;
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