Nakamichi OMS-7 User manual

Service Manual
Nakamichi
Nakamichi

CONTENTS
Ne
10.
11.
12.
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ay
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Pickup.
Replecetnent
Procedures
3
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2,
1
Notice
in
Handling
Pickup...
06.
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lll,
2
2.
2:
Pickup
Replacement
Procedures
...........
0.0...
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2
2.
8.
Adjustment
After
Replacement
of
Pickup
....................00.00..000000000002
3
Measurement
Instruments
and
Test
Discs
.....
2.0.0.0...
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4
Parts
Location
for
Adjustment
..
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4,
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Pacts
On
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4
4,
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5.
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5
5.
2.
Adjustment
Instructions
..
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5
Mechanism
Ass’y
and
Parts
List...
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6.
1.
Oy
VDGHIB
fede
sais
ata
ieritndy
ie
gear
mien
aired
Ghee
kod.
a
ane
Na
dna
arom
de
hand
Sooo
eae
10
6.
2.
Prone
Panel:
Bag
y
(AOL):
os
i.5
4
squat
oy
<a
es
a
avece-soidh’y
aed
baw
saranda
d
ahn
un
Be
Base
es
ee
11
6.
3.
Canals
Asa'y
(AQZ)
ooo
st
acs
oihene
a/v
Sb
Pace
a
ead
dood
Ak
Blah
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Woe
ae
dete
12
6.
4.
Disc
Mechanism
Ass’y
(B01)...
1...
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ell.
13
6.
5.
Rear
Panel
Ass’y
(B02)
.....
0.0...
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c
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eee
cece.
Si
4S
ce
gh
eed
atten
ete
wetahs
15
6.
6.
Disc
Mechanism
Sub
Ass’y
(C01)...
cece
ence
eben
eee.
15
6.
7.
Analog
Processor
Unit
(D01)
2.0.6...
.
eee
ec
cece
eet
nee
n
cence,
16
Mounting
Diagrams
and
Parts
List...
0.6.0...
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cece
ete
ete
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ence
c
eel
17
Te.
A
Photo
Transistor
P.C.B.
Assy
60...
0...
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ence
ences
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17
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2%
Photo:
Diode
PCB.
Ags
ye
5
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cao
sa
than
arden
¥
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oan
6/d
bod
GR
Bev
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nn
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kes
17
7.
8.
Open'End
Switch
PCB.
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you
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died
alecg
ver
ha.
Fd
he
Weeder
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17
7.
4,
Close
End
Switch
P.C.B.
Ass’y
2.0...
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17
7.
5.
Eject/Load
Switch
P.C.B.
Ag
Yi.
cees
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Lvae
sect
etetevivenceuccnr
en,
17
7.
6.
Power
Switch
P.C.B.
Assy
2...
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enc
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cee.
17
7.
7.
MOMS
PCBs
ABS
Ya
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ose
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545
sare
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diy
GE
wh
a
SS
5
wsh-w
Se
leads
|
teri
dole
Oo
17
7.
8.
Remote
Control:
P.C.B
Assy
i
..0
63g
6
agen
dois
een
ig
bod
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17
7.
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BC
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ty
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Siac
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De
18
7.
10
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Indicator
CB
Aggy.
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s
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ack
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18
7.11
Headphone
Amp.
P.C.B.
Ass’'y
.
1...
cet
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nee
ce
en.
19
7.
12.
Auto
Power
Control
P.C.B,
Ass’y.
2...
2.
ke
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beeen cece.
19
7.
18.
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AS:
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24
ake
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20
7.
14,
Powersupply
PCB.
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2
ono
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ouch
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21
7.
15.
Control
Switch
P.C.B.
Ass’'y
6...
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22
7.
16,
Analog
Processor
P.C.B.
Ass’Y
6...
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cele,
22
Teli:
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Converter
PCB
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wart
Goes
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«
26
Schematic
Diagrana
soo.
2.4.5
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held’
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Lode
64-9
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8.
1.
IC
Block
Diagrams
and
Descriptions
........0...0.00
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27
8.
2.
Waveforms
at
Major
Points
.....
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37
8.
3.
Dchemaue
Diagram
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Control
Transmitter
Unit
RM-7
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Mechanism
Ass’y
and
Parts
List...
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11.
2.
Mounting
Diagram
and
Parts
List...
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11.
38.
mchematic-
Diagram.
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42

1, GENERAL
1.1, Voltage Selector
Voltage
selector
is
installed
on
the
rear
panel
for
Other
version
of
the
Nakamichi
OMS-7,
This
voltage
selector
can
select
either
120
V
or
220-240
V
at
customer’s
disposal,
1.2. Packing Materials and Owner's Manual
Part
No.
Description
Q'ty
0C81046A
Outer
Carton
OMS-7
1
0C81081A
Outer
Carton
OMS-7E
1
0C81082A
Outer
Carton
OMS-70
(Japan)
1
0C81047A
Inner
Carton
OMS-7
1)
0C81085A
Inner
Carton
OMS-7E
1
0C81086A
Inner
Carton
OMS-70
(Japan)
1
0C81051A
_
Side
Packing
L
1
0C81050A
_
Side
Packing
R
1
0C81052A
Mirror
Mat
Bag
1
0D04491A
Owner’s
Manual
OMS-7
&
OMS-5
(English)
1
0D04493A
Owner's
Manual
OMS-7/7E
&
OMS-5/5E
1
(English /German/French)
0D04492A
‘Owner’s
Manual
OMS-70/50
(Japanese)
1
WARNING:
To
protect
eyes
from
laser
beam
during
servicing,
DO
NOT
LOOK
AT
THE
LASER
BEAM.
Note: Laser Diode Properties
Material: GaAlAs
Wavelength: 790 nm — 820 nm
Emission Duration: continuous
Laser
Output:
0.7
mW
max,
Classification:
Class
III
b
2. PICKUP REPLACEMENT PROCEDURES
2.1. Notice in Handling Pickup
In case of repair or replacement of the Pickup, pay attention to
the following handling instructions since the laser diode in the
Pickup is not resistant to static electricity.
(1) Repair or replace on a work stand on which the conducting
rubber is spread.
(2) Use ceramic soldering iron with GND.
(8) Since Pickup is supplied as a spare part in a conductive bag,
take it out of the bag only when you need it,
(4) Remove the shorting pin and conductive sponge that short the
connector pins of the Pickup after entire work is completed.
(5) Do not turn the adjustment screws (Focus Screw, RF Signal
Phase Screw and Tracking Screw) of the Pickup. If they are
turned widely, it may take much time to readjust them.
2.2, Pickup Replacement Procedures
(1) Place the Compact Disc Player upside down on the work
stand and remove the Bottom Cover by unfastening 10
screws,
(2)
Rotate
the
pulley
of
the
Disc
Mechanism
Ass’y
to
move
the
Fig,
2.2
Pickup
in
the
direction
of
the
arrow.
See
Fig.
2.1.
(3) Remove FO1, F02 and FO3, and pull out F04. See Fig. 2.2,
(4)
Remove
F05,
FO6
and
FO7,
and
pull
out
FO8.
See
Fig.
2.3.
Fig.
2.1
Fig.
2.3

(5)
Remove
two
connectors,
unsolder
the
two-core
shield
cable,
and
unsolder
F09
to
separate
FO9
from
the
Pickup.
See
Fig.
2,4,
(6)
Loosen
F10
and
remove
F11
(Pickup).
See
Fig.
2.5.
(7)
Mount
a
new
Pickup
and
temporarily
fasten
it
with
F10.
See
Fig,
2.5.
(8)
Remove
the
conductive
sponge
of
the
new
Pickup,
(9)
Mount
F09
on
the
new
Pickup
by
soldering,
Plug
in
the
two
connectors
and
solder
the
two-core
shield
cable
to
the
Original
place.
Soldering
of
the
shield
cable
must
be
made
in
the
order
of
GND
wire
with
black
tube
and
then
signal
wires,
(10)
Mount
the
new
Pickup
by
reversing
the
disassembly
Procedures,
(11)
Pull
F12
(shorting
pin)
out
of
the
Pickup.
See
Fig.
2.6.
Fig. 2.4
Fig. 2.6
2.3. Adjustment After Replacement of Pickup
Upon completion of replacement of the Pickup, perform rough
adjustments following the flow chart shown in Fig, 2,7. Then
proceed
to
the
final
stage
adjustment,
ie.,
‘Adjustment
Instructions”’
in
item
5.2
except
step
1
‘“‘Laser
Power
Adjustment”
(step 1 is already done in the rough adjustment),
START
Laser Power Adjustment
as per Step 1
Offset Adjustment of Focus
Servo (TP7, RV105)
as per Steps 2-1 & 2-2
Tracking Servo Adjustment
(TP6, RV102, RV103)
as per Steps 3-1 to 8-5
Focus Screw Adjustment
(TP7, Focus Screw)
as per Steps 4-4 & 4-5
RF Signal Phase Alignment
(TP1, RF Signal Phase
Screw)
as per Steps 5-4 & 5-5
Tracking Screw Adjustment
(TP1, Tracking Screw)
as per Steps 6-3 & 6-4
DL Signal Adjustment
(Emitter of Q103, RV101)
as per Steps 3-6 &3-7
EFM Signal Adjustment
(TP1, RV104)
as per Step 3-8
Are
EFM signal
at TP1 & playback
sound clear
2
Adjustment for Scratch and
Dot on Disc
as per Step 10
Fig. 2.7

3.
MEASUREMENT
INSTRUMENTS
AND
TEST
DISCS
(1)
Synchroscope
(15
MHz
or
more)
(7)
LPF
(Low
Pass
Filter):
(2)
VTVM
Pass
Band
—
4
Hz
to
20
kHz,
Attenuation
—
60
dB
or
more
(3)
DC
Voltmeter
for
24.1
kHz
or
higher
frequency
(4)
Optical
Power
Meter
Recommended
LPF:
Philips
Type
7122
780
29020
(5)
Philips
Test
Sample
Disc
5A
(8)
Distortion
Meter
(6) Sony Test C.D. YEDS-7
4.
PARTS
LOCATION
FOR
ADJUSTMENT
4.1, Parts on P.C.B. Ass’y
8
[b3000005}
|
Main
P.C.B.
CN201
D/A Converter PC.B.
RVSO1
Audio Signa!
Belonce
RMOS 180n
—--
onsfifone
Laser Power
RVMOI
Auto Power Control P-C.B,
RVIOS RVIO4
@ TPG Te7
®
© RvIWS
RVIIO
Pickup Movement
Fig. 4.1
4.2, Parts on Pickup
RF
Signal
Phase
Adjustment
Screw
Focus
Screw
Tracking
Adjustment
Screw
Lock Screws
for
Focus
&
RF
Signal
Phase
Adjustment
Lock Screws
for Tracking Adjustment
Fig. 4.2

5. ADJUSTMENTS
5.1. Note
Pay attention to the following before adjustment.
(1)
Keep
the
Compact
Disc
Player
horizontal
during
adjustment,
(2) Before starting adjustment, allow three minutes after the
power
is
turned
ON.
Offset
voltate
will
be
stabilized
in
this
Period of time.
(3)
When
a
Philips
5A
test
disc
is
used,
perform
the
adjustment
while
listening
to
the
playback
sound.
(4)
Connect
a
low
pass
filter
(pass
band:
4
Hz
to
20
kHz)
in
series
to
the
distortion
meter
to
be
used.
(5)
When
the
Main
P.C.B,
Ass’y
is
replaced
with
new
one,
set
each
of
the
potentiometers
as
follows:
RV106,RV107: 1 o’clock direction (marked on the
P.C.B.)
RV108: 10 o’clock direction (marked on the
P.C.B.)
Others: Mechanical center positions
5.2, Adjustment Instructions
Auto Power
Control
P.C.B.
RVMO1
Optical
Power Meter
to Pickup
Lens
or
DC Voltmeter
across RMO9
on Auto
Power
Control
P.C.B.
Adjustment
(6)
Potentiometers
that
are
not
stated
in
the
adjustment
instructions
must
be
set
to
the
preset
positions
stated
in
(5),
(7)
When
the
Auto
Power
Control
P.C.B.
Ass’y
or
Pickup
is
replaced
with
new
one,
turn
the
potentiometer
RVMO1
full
counterclockwise
to
prevent
damage
to
the
Pickup,
(8)
Keep
the
Pickup
Lens
clean,
Carefully
clean
it
with
lens
cleaner
or
similar
tools,
Danger:
Invisible
laser
radiation
when
opened
and
interlock
failed
or
defeated.
Avoid
direct
exposure
to
beam.
1. Using Optical Power Meter
a.
Unsolder
one
of
the
leads
of
diode
D135
on
the
Main
P.C.B.
Ass'y.
b. See Fig. 5.1. Remove the Feed Motor Belt and,
with
rotating
the
Pulley,
position
the
Pickup
so
that
an
optical
power
meter
can
be
put
onto
the lens of the Pickup.
Position
the
optical
power
meter
at
such
a
position
and
angle
that
provide
maximum
power
meter
reading.
c.
Check
that
RVMOl
is
at
full
counterclockwise
position,
and
then
turn
ON
the
power.
Rotate RVMO1 slowly clockwise until the power
meter reads 0.27 mW.
Caution:
Use
care
not
to
exceed
0.3
mW
at
any
moment,
otherwise
Pickup
will
be
damaged.
e.
Turn
OFF
the
power
and
then
solder
the
lead
of
D135 and put the belt on the feed motor.
Qa
.
. Without using Optical Power Meter
a.
Unsolder
one
of
the
leads
of
diode
D135
on
the
Main P.C.B. Ass'y.
b.
Connect
a
DC
voltmeter
across
RMO9
(180-ohm
1
W)
on
the
Auto
Power
Control
P.C.B.
Ass'y.
ce.
Check
that
RVMO1
is
at
full
counterclockwise
position,
and
then
turn
ON
the
power.
d.
Rotate
RVMO1
slowly
clockwise
until
the
reading
on
the
DC
voltmeter
reaches
90%
of
the
operating
current
Iop.
lop
is
marked
on
the
Pickup
(however,
it
is
actually
marked
as
Io).
Example:
If
Iop
is
37
mA,
the
voltmeter
reading
which corresponds to 90% of Iop is
0.037
(A)
x
0.9
x
180
(ohms)
=
5.99
(Vv).
Caution:
Use
care
not
to
exceed
Iop
at
any
moment, otherwise the Pickup will be
damaged.
In
this
example
(Iop
=
37
mA),
the
limit
is
6.66
V.
e.
Turn
OFF
the
power
and
then
solder
the
lead
of
D135.

ITEM SIGNAL OUTPUT
SOURCE CONNECTION
2
|Focus
Servo}Test
Disc|Synchroscope|
Main
P.C.B.
Adjustment
|
Philips
|to
TP1,TP7
RV104
,RV105
|
4
1.
Set
a
synchroscope
to
DC
input
and
50
mv/div.,
and
connect
it
to
TP7.
2. Adjust RV1O5 to obtain 0+50 mV on the
synchroscope,
3.
Connect
the
synchroscope
to
TP1
and
play
back
the
test
disc.
4.
While
listening
to
the
playback
sound,
adjust
RV104
so
that
the
horizontal
waving
of
the
EFM
(Eight-to-Fourteen
Modulation)
signal
at
TP1
is
minimized
and
the
EFM
signal
waveform
becomes
clear. See Pig. 5.2.
5A on Main
P.C.B.
Test Disc
Philips
5A
Tracking
Servo
Adjustment
Synchroscope| Main P.C.B.
to TP1,TP6, RV101,RV102
emitter of RV103 ,RV104
Q103 on
Main P.C.B.
+
Set
a
synchroscope
to
DC
input
and
50
mV/div.,
and connect it to TP6.
2.
Adjust
RV103
to
obtain
0-100
mV
on
the
synchro-
scope.
3. Short between pins 4 (A+C signal) and 5 (GND)
of CN201 and between pins 6 (GND) and 7 (B+D
signal)
of
CN201
on
the
Main
P.C.B.
Ass'y,
Short
between
the
emitter
and
the
base
of
Q113
on the Main P.C.B. Ass'y.
4.
Adjust
VR102
to
obtain
0-50
mV
on
the
synchro-
scope,
5.
Remove
the
short
of
CN201
and
Ql13.
6.
Connect
the
synchroscope
to
the
emitter
of
Q103
and
play
back
the
test
disc,
7.
Adjust
RV101
to
obtain
minimum
DL
signal
(RF
error
signal)
on
the
synchroscope,
8.
Connect
the
synchroscope
to
TP1
and,
while
listening
to
the
playback
sound, adjust
RV104
so
that
EFM
signal
is
maximized
and
becomes
clear,
Focus
Screw|/Test
Disc
|Synchroscope|Main
P.C.B.
Adjustment
i
Loosen
the
two
Lock
Screws
used
for
focus
adjustment
by
referring
to
Fig.
4.2.
2.
Set
a
synchroscope
to
DC
input
and
50
m/div.,
and
connect
it
to
TP7.
3. Adjust RV105 to obtain 0+50 mv on the syncro-
scope, i
4.
Play
back
the
7th
or
8th
music
on
the
test
disc,
5.
While
listening
to
the
playback
sound,
adjust
the
Focus
Screw
of
the
Pickup
to
obtain
exactly
or
approximately
0
V
on
the
synchroscope.
6.
After
completion
of
adjustment,
securely
tighten
the
Lock
Screws
alternately,
Focus Screw
Optical
Power Meter
se
Sees
2 AWE
AN ie
XK?
ORR RRR
Ce SSN SSS
Fig. 5.2 EFM Signal at TP1

SIGNAL OUTPUT
SOURCE CONNECTION
Test Disc|Synchroscope|Main P.C.B.
Philips RV104
5A
Loosen
the
two
Lock
Screws
used
for
RF
signal
phase
alignment
by
referring
to
Fig.
4.2.
2.
Connect
a
synchroscope
to
TPl
and
play
back
the
test
disc.
3.
While
listening
to
the
playback
sound,
adjust
RV104
so
that
the
horizontal
waving
of
the
EFM
signal
at
TPl
is
minimized
and
the
EFM
signal
becomes
clear,
4.
Play
back
the
7th
or
8th
music
on
the
test
disc.
5.
Adjust
the
RF
Signal
Phase
Screw
of
the
Pickup
so
that
the
EFM
signal
waveform
at
TPl
becomes
clear
and
maximized
and
that
its
horizontal
waving
is
minimized.
6.
Repeat
2.
to
5.
above
two
or
three
times,
7.
Securely
tighen
the
Lock
Screws
alternately,
RF Signal
Phase
Adjustment
RF Signal
Phase Screw
Loosen
the
two
Lock
Screws
used
for
tracking
adjustment
by
referring
to
Fig.
4.2.
2.
Conduct
step
3
"Tracking
Servo
Adjustment",
3.
Connect
a
synchroscope
to
TPl
and
play
back
the
7th
or
8th
music
on
the
test
disc.
4.
While
listening
to
the
playback
sound,
adjust
the
Tracking
Screw
of
the
Pickup
so
that
the
EFM
signal
at
TPl
becomes
clear
and
maximized.
5.
Connect
the
synchroscope
to
the
emitter
of
Q103
and
adjust
RV101
to
obtain
minimum
DL
signal
on
the
synchroscope.
6.
While
listening
to
the
playback
sound,
adjust
RV104
so
that
the
EFM
signal
at
TP]
is
maximized and becomes clear,
Securely
tighten
the
Lock
Screws
alternately.
Tracking
Screw
Adjustment
Test Disc| Synchroscope| Tracking
Philips to TP1,TP6,
emitter of
Q103 on Main|Main P.C.B.
P.C.B. RV101,RVi02
RV103 ,RV104
Connect
a
synchroscope
to
the
test
point
CT1
and
play
back
the
18th
music,
Finger
Print,
on
the
test
disc.
2.
While
listening
to
the
playback
sound
and
observing
the
VCO
signal
level
on
the
synchro-
scope,
turn
the
core
of
L501
counterclockwise
and
clockwise
to
find
out
the
upper
and
the
lower
limits
of
VCO
voltage,
i.e.,
the
limits
at
which
the
playback
sound
is
about
to
cut
off,
3.
Adjust
the
core
of
L501
so
that
the
VCO
level
is
the
midpoint
between
the
upper
and
lower
limit
voltages.
(This
VCO
level
will
be
approx. a little under 5.0 Vv).
Test Disc
Philips
5A
yvco
Adjustment
Synchroscope|D/A Converter
to test
point CT1 on
D/A
Converter
P.C.B.
Test Disc
Philips
5A
Synchroscope|Main P.C.B.
to anode of RV109,RV110
D138 (or pin
3 of U115),
anode of
D139 (or pin
11 of U115)
on Main
P.C.B.
Connect a synchroscope to the anode of the
diode D138.
2.
Play
back
the
test
disc
and
then
press
the
F.
Fwd
button
to
set
the
Compact
Disc
Player
in
Cue
mode,
3.
Adjust
RV109
to
obtain
a
180
psec
pulse
width.
See
Fig.
5.3.1.
4.
Press
the
F,
Fwd
button
further
several
times,
and
check
whether
the
time
indication
on
the
Time
Indicator
regularly
increases.
If
not,
repeat
3,
5.
Connect
the
synchroscope
to
the
anode
of
diode
D139.
6.
Play
back
the
test
dise
and
then
press
the
Rev
button
to
set
the
Compact
Disc
Player
in
Cue
mode,
(to be continued)
Pickup
Movement
Adjustment

Adjust
RV110
to
obtain
a
160
psec
pulse
width,
See
Fig.
5.3.2.
Press the Rev button further several times,
and
check
whether
the
Time
Indicator
regularly
changes
its
time
indication,
If
not,
repeat
7.
Audio
Test
Disc]
VIVM
to
Play
back
the
first
music
on
the
test
disc
to
Signal
Output
Pin
play
back
1
kHz
0
dB
level
signals.
Balance
Jacks
Measure
both
L
and
R
channel
output
levels
and
Adjustment
adjust
RV501
so
that
the
difference
between
them
is
less
than
0.1
V.
Adjustment
|Test
Disc|Synchroscope|Main
P.C.B.
1.
Scratch
900
»m
for
Scratch|
Philips
Play
back
the
9th
music
with
a
900
wm
scratch
on
and Dot
on
the
test
disc
and
listen
to
the
playback
sound,
Disc
If
playback
is
not
made
properly,
conduct
step
6
"Tracking
Screw
Adjustment",
Turn
the
Tracking
Screw
counterclockwise
when
tracking
stops,
but
turn
it
clockwise
when
track
is
skipped,
If
still
proper
playback
is
not
made
yet,
conduct
step
7
"VCO
Adjustment".
2. Black Dot 800 zm
Play
back
the
17th
music
with
a
800
ym
black
dot
on the test disc,
If
playback
is
not
made
properly,
that
is,
if
tracking
stops,
make
the
following
adjustment:
1.
Set
a
synchroscope
to
1
msec/div.
and
connect
it to TPl.
2.
Adjust
RV104
so
that
the
waveform
at
TP]
is
as
shown
in
Fig.
5.4.2
when
passing
through
a
black
dot,
satire
180 y Sec A \
\ }
/
~~”
F. Fwd.
Fest
Fig.
5.4.1
Before
Adjustment
ie
/ \
160
Sec
‘
/
No?
Rev.
Fig. 5.3.2
Fig. 5.4.2 After Adjustment

Perform this adjustment only if a disc with
eccentricity
is
not
played
back
properly.
Tracking
Adjustment
with
Eccentric
Disc
Precisely
re-adjust
Step
3
"Tracking
Servo
Disc
Adjustment"
and
Step
6
"Tracking
Screw
Adjustment",
and
check
whether
playback
is
made
properly.
tif
not,
perform
the
following
adjustment
to
insure
correct
tracking
for
a
0.1
mm
eccentric
disc,
1.
Preparation
for
0.1
mm
Eccentric
Disc
Find
a
disc
with
approx.
0.1
mm
eccentricity
in
the following manner:
a.
Set
a
synchroscope
to
DC
input
and
connect
it
to
the
positive
side
of
C173
on
the
Main
P.C.B.
Ass'y,
b.
Play
back
the
first
music
on
eccentric
discs
and
press
the
Pause
button
to
set
the
Com-
pact
Disc
Player
in
Pause
mode.
Then
observe
the
peak-to-peak
level
(Vpp)
on
the
Synchroscope.
The
amount
of
eccentricity,
X
(mm),
is
given
in
the
following
formula:
X
=
1/2
x
(1.3
x
(Vpp/(5.8
+
4.7))
sensitivity of Tracking
Servo
5.8 ohms: DC resistance value of
Traking Coil
4.7
ohms:
value
of
resistor
R197
where, 1.3 mm/A:
If
amount
of
eccentricity
(x)
is
assumed
to
be
0.1
m,
Vpp
=
2
x
(5.8
+
4.7)/1.3
x
0.1
=
1.6
(Vv)
That
is,
the
disc
which
shows
approx.
1.6
V
on
the
synchroscope
should
be
selected,
2.
Load
the
disc
found
in
1
above
and
play
back
the
first
music
of
the
disc.
Check
whether
it
takes
much
time
to
enter
Standby
mode
or
whether
the
time
indication
of
the
Time
Indicator
begins
with
00:00.
If not, re-adjust Step 3 "Tracking Servo
Adjustment"
and
then
turn
RV108
approx.
10
degrees
in
the
counterclockwise
direction.
3. During playback, press the F. Fwd button
several
times
and
check
that
the
time
indication
of
the
Time
Indicator
regularly
increases,
If not, turn RV109 to correct it,
4. Next, during playback, press the Rev button
several times to see whether the time
indication
of
the
Time
Indicator
regularly
decreases,
If
not,
turn
RV110
to
correct
it.