Sony CDP-H3700 - Electrical Block Checking; RF Level Check; S Curve Check; E-F Balance Check

I
sEcTtoN
3
ELECTRICAL
BLOCK
CHECKING
Note
:
1.
CD
Block
basically constructed
to operate without
adjus.
tment.
Therefore,
check
each item in
order
given.
2.
Use
YEDS-18
disc
(3-702.101-01)
unless otherwise indicat-
ed.
3.
Use the
oscilloscope with
more
than
10MO
impedance.
4.
Clean an object
lens by
an
applicator
with
neutral
deter-
gent
when
the
signal
level
is
low than
specified value
with
the
following
checks.
S
Curve Check
BD boarcl
rP(FEO)
rP(vc)
Procedure
:
l.
Connect oscilloscope
to
test
point
TP
(FEO)
on BD
board.
2.
Connect between
test
point
TP
(FES)
and
TP
(VC)
bv
lead wire.
Turned Power
switch
on
and actuate the
focus
serch.
(actuate
the focus
serch when
disc
table
is moving in
and
out.)
Check the
oscilloscope waveform
(S
curve)
is
symmetri.
cal
between
A
and B. And
confirm
peak
to
peak
level
within
3+ 1Vp-p.
S curve
wavelorm
symm€try
within
3
tlVÈp
5. After
check, remove
the lead
wire
connected
in
step 2.
Note
:
o
Try
to mesure
several
times
to
make
sure
that the
ratio
of A : B
or
B : A
is more
than 10
: 7.
o
Take sweep
time as long
as
possible
and light
up the
brightness
to obtain best waveform.
RF Level
Check
BD
board
TP(RFO)
rP(vc)
Procedure
:
1.
Connect
oscilloscope
to test
point
Tp
(RFO)
on BD
board
2. Turn
Power
switch
on.
3. Put
disc
(YEDS.l8)
in
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
"O"
can
be
clearly distinguished
at the
center
of the waveform.
RF
signal waveform
VOLT/DlV:
20OmV
TIME/O|V:
5O0nS
level :
I 2:3:l Vtp
E-F
Balance
Check
BP-
rP(TEO)
TP(VC)
l.
Connect
test
point
TP
(ADJ)
to
ground
and
Tp
(TES)
to
TP
(VC)
with
lead wire.
2. Connect
oscilloscope
to
test
point
TP
(TEO)
on BD
board.
3.
Turn
Power
switch
on.
4.
Put
disc
(YEDS-l8)
in
and
playback.
5
Confirm
that
the
osilloscope
waveform
is
symmetrical
on
the top
and
bottom in
relation
to 0V,
and
check this level
Traverse
oscilloscope
symrnetry
T
1
À
oscilloscope
oscilloscope
oscilloscooe
6.
Remove
the lead wire
connected
in
step I
2+
lVpp