Sanyo Dc-MS5 User manual

SANYO
Service
Manual
Micro
CD
Hi-Fi
DC-MS5-
(xe)
System
(UK
)
edi
-
sta
PRODUCT
CODE
No.
Specifications
129 475
00
(UK)
129 475 01 (XE)
Note:
|
The
below
mentioned
specifications
are
mainly
based
on
the
IHF
measurements
standard.
They
can
therefore
not
directly
be
compared
with
specifications
based
on
the
DIN
standard
or
other
standards.
TUNER
SECTION
AMPLIFIER
SECTION
Reception
frequency
.
FM:
87.5
-
108.0
MHz
Output
power
.......
20
W
x
2
(at 4
ohms,
MW
:
522
-
1,611
kHz
10%
distortion
)
LW
:
144
-
288
kHz
Sound
preset
.......
Four
electronic
presets
CASSETTE
DECK
SECTION
INPUTS»
-224
how
ia
VIDEO
IN
:
400
mV/50k
ohms
Track
system
.......
4
track,
2-channel
stereo
Outputs
...........
SPEAKER
:
4
ohms
Frequency
response
..
50
Hz
-
14,500
Hz
(CrO2
type)
PHONES
:
8
-
32
ohms
50
Hz
-
13,500
Hz
(Normal
type)
Power
requirements
..
AC:
230
V,
50
Hz
Signal
to
noise
ratio
..
60
dB
(
Dolby
NR
ON
)
Power
consumption
..
75
W
Wow
&
Flutter
.....
%;:0.12
%
(WRMS)
Dimensions
(WxHxD)
.
Approx.
180
x
260
x
288
mm
Tape
speed
........
4.75
cm/sec
Weight
........-.--
Approx.
5.7
kg
Fast
forward
and
rewind
time
....
Approx.
110
sec.
(C-60)
SPEAKER
SYSTEMS
CD
PLAYER
SECTION
he
Typeset
sas
asre
2
way
bass
reflex
TY
D6)
Sec
daee
Meat
es
Changer,
3-disc
Unit
used
..........
Woofer:
10
cm
cone
type
Channels
......-5-.
2-channel
stereo
:
Tweeter
:
piezoelectric
Sampling
frequency
..
44.1
KHz
_
ue
Maximum
power-handling
capacity
40
W
(peak)
Pick-up
.......-000-
Optical
3-beam
semiconductor
laser
Nominal
impedance
..
4
ohms
Laser
output
........
0.6
mW
(Continuous
wave
max.)
Dimensions
(WxHxD)
.
Approx.
165
x
260
x
215
mm
Wave
length
........
*
790
nm
Weight
..........-.
Approx.
1.7
kg
(per
speaker)
Frequency
response
..
20
Hz
-
20,000
Hz
;
Wow
&
Flutter
......
Below
measurable
limits
=.
Specifications
subject
to
change
without
notice.
This
service
manual
consists
of
“DC-MS5U"(
main
unit
),
“RB-MS5”
(
remote
control
),
“SX-MS5”
(speaker
system).
~
REFERENCE
No.
SM580567

CONTENTS
SPECIFICATIONS
............-5
TOP
TUNER
ADJUSTMENTS
LASER
BEAM
SAFETY
PRECAUTIONS
.
1
EXPLODED
VIEW
......-..
ee
eaae
WHAT
TO
DOIF
...
1...
ee
eee
eee
eee
2
PARTS
LIST
......
2.22
eee eee
ees
REMOVAL
AND
INSTALLATION
.....-.
2
TEST
CABLES
.......
eee
eee
ene
CD
CHANGER
OPERATION
SCHEMATIC
DIAGRAM
DESCRIPTION
.......
eee
eee
eee
6
WIRING
DIAGRAM
CD MECHANISM ADJUSTMENTS ..... 9 IC BLOCK DIAGRAM &
CD
PLAYER
ADJUSTMENTS
.......
13
DESCRIPTION
..........
cece
eee
TAPE
DECK
ADJUSTMENTS
.......-
15
LCD
DESCRIPTION
AMPLIFIER ADJUSTMENTS ........ 17 IC & TRANSISTOR VOLTAGES
LASER BEAM SAFETY PRECAUTIONS
e Pick-up that emits a laser beam is used in this CD player.
CAUTION :
USE OF CONTROLS OR ADJUSTMENTS
OR PERFORMANCE OF PROCEDURES
OTHER THAN THOSE SPECIFIED
HEREIN MAY RESULT IN HAZARDOUS
RADIATION EXPOSURE
LASER OUTPUT 0.6 mW Max. (CW)
WAVELENGTH 790 nm
CLASS 1 LASER PRODUCT
LUOKAN 1 LASERLAITE
KLASS 1 LASERAPPARAT
CAUTION ~ INVISIBLE LASER RADIATION WHEN OPEN AND
NTERLOCKS DEFEATED. AVOID EXFOSURE Ti GrAM.
ADVARSEL ~ USYNLIG LASER STRALING VED ABNING, NAR
SIKKERHEDSAFBRY DERE ER UDE AF FUNKTION, UNDGA UDS ATTELSE
FOR STRALING. Boece ae te we ee,
VARNING ~ OSYNLIG LASER STRALNING NAR DENNA DEL AR OPPNAD
OCH SPARR AR URKOPPLAD. STRALEN AR FARLIG.
VORSICHT ~ UNSICHTBARE LASERSTRAHLUNG TRITT AUS, WENN
DECKEL GEOFFNET UND WENN SICHERHEITSVERRIEGELUNG
UBERBRUCKT IST. NICHT, DEM STRAHL AUSSETZEN.
VARO! Avattaessa ja suojalukitus ohitettaessa olet alttiina
ndkymattémalle lasersatellylle. Ala katso aleeseen.

ZO40
S O
Service
Manual
Micro
CD
Hi-Fi
DC-MS5
(xe)
System
(UK)
aati
ees
PRODUCT
CODE
No.
p
429
475
00
(UK)
129 475 01 (XE)
Note:
|The
below
mentioned
specifications
are
mainly
based
on
the
IHF
measurements
standard.
They
can
therefore
not
directly
be
compared
with
specifications
based
on
the
DIN
standard
or
other
standards.
TUNER
SECTION
AMPLIFIER
SECTION
Reception
frequency
.
FM:
87.5
-
108.0
MHz
Output
power
.......
20
W
x
2
(at
4
ohms,
MW
:
522
-
1,611
kHz
10%
distortion
)
LW
:
144
-
288
kHz
Sound
preset
.......
Four
electronic
presets
CASSETTE
DECK
SECTION
INPULS:
2
ees
eae
VIDEO
IN
:
400
mV/SO0k
ohms
Track
system
.......
4
track,
2-channel
stereo
Outputs
.....-..---
SPEAKER
:
4
ohms
Frequency
response
..
50
Hz
-
14,500
Hz
(CrO2
type)
PHONES
:
8
-
32
ohms
50
Hz
-
13,500
Hz
(Normal
type)
Power
requirements
..
AC
:
230
V,
50
Hz
Signal
to
noise
ratio
..
60
dB
(
Dolby
NR
ON
)
Power
consumption
..
75
W
Wow
&
Flutter
.....
*-0.12
%
(WRMS)
Dimensions
(WxHxD)
.
Approx.
180
x
260
x
288
mm
Tape
speed
........
4.75
cm/sec
Weight
.......-----
Approx.
5.7
kg
Fast
forward
and
rewind
time
....
Approx.
110
sec.
(C-60)
SPEAKER
SYSTEMS
CD.
PLAYER
SECTION
Type
.
2.
cece
eee eee
2
way
bass
refiex
Type
..
cece
eee
Changer,
3-disc
Unit
used
......-.--.
Woofer:
10
cm
cone
type
Channels
........--.
2-channel
stereo
Tweeter
:
piezoelectric
Sampling
frequency
..
44.1
kHz
Maximum
power-handling
capacity
40
W
(peak)
Pick-up
...-.2--00--
Optical
3-beam
semiconductor
laser
Nominal
impedance
..
4
ohms
Laser
output
.....--:
0.6
mW
(Continuous
wave
max.)
Dimensions
(WxHxD)
.
Approx.
165
x
260
x
215
mm
Wave
length
.....--.
790
nm
Weight
......---+--
Approx.
1.7
kg
(per
speaker)
Frequency
response
..
20
Hz
-
20,000
Hz
Wow
&
Flutter
......
Below
measurable
limits
—
Specifications
subject
to
change
without
notice.
This
service
manual
consists
of
“DC-MS5U"(
main
unit
),
“RB-MS5"
(remote
control
),
“SX-MS5”
(speaker
system)
.
REFERENCE No. SM580567
ROPE

CONTENTS
SPECIFICATIONS
..............
TOP
TUNER
ADJUSTMENTS
...........
18
LASER
BEAM
SAFETY
PRECAUTIONS
.
1
EXPLODED
VIEW
............--4-
19
WHAT
TODOAPF
sks
52e
ca
brand
Rowe
2
PARTS
{LIST
aiceraas
ene!
20
REMOVAL
AND
INSTALLATION
......
2
TEST
CABLES:
22.5
feces
eeks
27
CD
CHANGER
OPERATION
SCHEMATIC
DIAGRAM
............
34
DESCRIPTION
........--c000eeeee
6
WIRING
DIAGRAM
...............
36
CD MECHANISM
ADJUSTMENTS
..... 9
IC
BLOCK
DIAGRAM
&
CD PLAYER ADJUSTMENTS ....... 13 DESCRIPTION ...............00. 37
TAPE DECK ADJUSTMENTS ....... 15 LCD DESCRIPTION .............. 69
AMPLIFIER ADJUSTMENTS ........ 17 IC & TRANSISTOR VOLTAGES ..... 70
LASER BEAM SAFETY PRECAUTIONS
e@ Pick-up that emits a laser beam is used in this CD player.
CAUTION :
USE OF CONTROLS OR ADJUSTMENTS
OR PERFORMANCE OF PROCEDURES
OTHER THAN THOSE SPECIFIED
HEREIN MAY RESULT IN HAZARDOUS
RADIATION EXPOSURE
LASER OUTPUT 0.6 mW Max. (CW)
WAVELENGTH 790 nm
CLASS 1 LASER PRODUCT
LUOQKAN 1 LASERLAITE
KLASS 1 LASERAPPARAT
[ CAUTION - INVISIBLE LASER RADIATION WHEN OPEN AND
INTERLOCKS DEFEATED. AVOID EXPOSURE TO BEAM. H
ADVARSEL ~ USYNLIG LASER STRALING VED ABNING, NAR
SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION, UNOGA UDS ATTELSE
FOR STRALING.
VARNING - OSYNLIG LASER STRALNING NAR DENNA DEL AR OPPNAD
OCH SPARR AR URKOPPLAD. STRALEN AR FARLIG.
VORSICHT — UNSIGHTBARE LASERSTRAHLUNG TRITT AUS, WENN
DECKEL GEOFFNET UND WENN SICHERHEITSVERRIEGELUNG
UBERBRUCKT IST. NICHT, OEM STRAHL AUSSETZEN.
VAROI! Avattaessa ja suojalukitus ohitettaessa olet aittina |
nakymattémalle lasersdleilylle. Ala katso ateeseen.
-~1-

WHAT TO DO IF
If the operation of the unit or display is not normal,
or you wish to clear the contents of the memory.
te
[s)
REMOVAL AND INSTALLATION
Disconnect the power cord’s plug from the
electrical outlet.
. Press the RESET button for at least 30 seconds.
. Connect the power cord.
. Press the POWER button to turn the power on.
@ Disconnect the power cord’s plug from the electrical outlet.
e All wiring should be returned to the original position after work is completed.
e@ First have ready many the new FIXERS (614 129 2496) for replacement.
@ Arrange the lead wires so that they are not near the heat sink.
a.
CABINET
(1) Remove the 7 rear panel mounting screws. (@)
(2) Remove the 6 cabinet mounting screws. (@)

REMOVAL AND INSTALLATION
b.
c.
d.
CD BLOCK
(1) Remove the 2 CD mechanism mounting screws. (D)
(2) Remove the CD mechanism. (@)
FRONT PANEL & PRE-AMP.
P.W.BOARD
(1) Remove the front panel. (D)
(2) Remove the connector. (@)
POWER AMP. & SPEAKER TERMINAL
P.W.BOARD
(1) Remove the 5 heatsink mounting screws. (@)
(2) Remove the POWER AMP. P.W.Board mounting
screws. (@)
(3) Remove the connector. (@)

REMOVAL AND INSTALLATION
e.
TAPE
MECHANISM
f.
FRONT
P.W.BOARD
(1) Remove the 4 tape mechanism
mounting screws. (@)
(2) Open the cassette compartment lid. (@)
(3) Remove the mechanism.
g. WIRING LAYOUT
(b)
CD
MECHANISM
&
CD
P.W.BOARDS
(a) POWER TRANSFORMER
:@
Arrange
the
lead
wires
so
that
they
are
not
near
the
heat
sink
of
the
POWER
AMP.
P.CW.Board.
SPINDLE/SLED MOTOR PWB
CONNECTOR PW.B

REMOVAL AND INSTALLATION —H-_-—————-
h. CD CHANGER MECHANISM
(a) CHUCK BRACKET (503)
(1) Rotate the UP/DOWN CAM GEAR (602). (©)
(2) Remove the 3 CD changer mechanism mounting
screws. (@)
(3) Remove the chuck bracket. (@)
We oe CAM GEAR
(b) DISC STOPPER (572)

CD CHANGER OPERATION DESCRIPTION
e This set is capable of stocking and playing up to 3 CDs.
® While playing a CD, other discs can be replaced.
In this case, press the button for the disc No. you wish to remove, and then press the OPEN/CLOSE button.
@ When the ”"POWER?” button is turned off, the power turns off after the discs are loaded in the disc trays.
a. MOTOR & MECHANISM SWITCHES LAYOUT
LOAD/UNLOAD MOTOR
LOAD SWITCH(SW3)
PLAY SWITCH (SW4)
NK | ee . 4 /
SEM == as SPINDLE MOTOR
DISC
1
a
L<
SLED MOTOR
DISC 2
DISC 3 UP/DOWN MOTOR
SJ
CLOSE END SWITCH
OPEN/CLOSE RACK GEAR
OPEN/CLOSE IDLER GEAR
aes IDLER PULLEY
OPEN/CLOSE LEVER
TRAY GUIDE TRAY
qoser ir REDO oO
ir ——
CLOSE OPEN
(/) ~>X_|-— OPEN/CLOSE MOTOR
GEAR BLOCK BRACKET BELT
OPEN ENO SWITCH

CD CHANGER OPERATION DESCRIPTION
b. UP/DOWN FUNCTION ( DURING ”UP” )
(1) The rotation of the UP/DOWN MOTOR (624) rotates the UP/DOWN DRIVE GEAR (605) in the counter-clockwise direction.
(2) in connection with this, the TRAY HOLDER SLIDE (640) moves forward, and at the same time, the RIGHT SLIDE (575) is
moved backwards by the SYNCRO LEVER (632).
UP/DOWN CAM GER 1 (602)
UP/DOWN
DRIVE
GEAR?
UP/DOWN
IDLER
2
(609)
(605)
UP/DOWN
IDLER
1
(607)
UP/DOWN MOTOR (624)
UP/DOWN
ORIVE
GEAR
1
|
UP/DOWN
CAM
rae
1
UP/DOWN
602)
|
“8
-\
SI
oe
Tinie
VV
TET
lait
as
It—
UP/DOWN
IDLER
1
(607)
UP/DOWN
DRIVE
GEAR
2
UP/DOWN
IDLER
2
(609)
(606)
UP/DOWN
CAM
GEAR
2
(603)
Pag
ar
a
Sf
=
TRAY HOLDER
: (560)
a
UP/DOWN
DRIVE
GEAR
1
TRAY
HOLDER
SLIDE
XS
SYNCRO LEVER (632)
UP/ DOWN
DRIVE GEAR2
(603) ;

CD CHANGER OPERATION DESCRIPTION
c. LOAD/UNLOAD FUNCTION
(1) The rotation of the LOAD/UNLOAD MOTOR rotates the LOAD/UNLOAD DRIVE GEAR (552) in the clockwise direction.
(2) The DRIVE GEAR and the gear portion of the TRAY mesh together and the TRAY moves backwards.
(3) The completion of TRAY movement causes the UP/DOWN MOTOR to operate and lower the TRAY HOLDER, putting the
unit to chucking stayus.
Y
LOAD/UNLOAD DRIVE GEAR
(552)
fESA9
RIGHT SLIDE
d. OPEN/CLOSE MECHANISM
(1) The rotation of the OPEN/CLOSE MOTOR rotates the
OPEN/CLOSE IDLER GEAR via the BELT and PULLEY,
and the RACK GEAR whitch is intermeshed with the
OPEN/CLOSE IDLER GEAR moves forward during "OPEN”,
backwards during "CLOSE”.
CLOSE END SWITCH (Sw 2)
OPEN/CLOSE RACK GEAR
OPEN/CLOSE IDLER GEAR
OPEN/CLOSE IOLER PULLEY
OPEN/CLOSE LEVER
TRAY GUIDE TRAY
rasa
Ty
14
CLOSE OPEN
ce
{/ OPEN/CLOSE MOTOR
ous
GEAR BLOCK BRACKET BELT
OPEN ENO SWITCH (SW 1)
~8-

CD MECHANISM ADJUSTMENTS
a.
CD CHANGER MECHANISM AND OPEN/CLOSE MOTOR :
atk
Bo
2
a ?5 -t
Wu 3
uw
2
9
fs
Bu
a
x£o
x
2
#8
=z
O29
2ok
b. UP/DOWN. GEAR
c. CD MECHANISM BLOCK
)
3)
a
oO Ww

CD MECHANISM ADJUSTMENTS
d. LOAD/UNLOAD MOTOR
LOAD/UNLOAD CAM GEAR
LOAD/UNLOAD MOTOR
LOAD/UNLOADIOLER 1
LOAD/ UNLOAD IDLER 2
LOAD/UNLOAD DRIVE GEAR
e.
TRAY
HOLDER
f.
CD
MECHANISM
BLOCK
A B-TOP ENCOURAGE
CHUCK BRACKET 2.
?
a ; ;

CD MECHANISM ADJUSTMENTS
g- REPLACEMENT AND LUBRICATION OF THE CD MECHANISM
Note :
;EM-50L Cte teie ie wets MOLYKOTE, EM-50L :
:SG-7 Sia ecuservceaioce ee aeere SAN GREASE, SG-7 :
sec e nett eeene FLOIL OIL, G-474B
h. CD BASE MECHANISM
SPINOLE MOTOR
SLED
MOTOR
SLED RETARD GEAR 1 |
SLED RETARD GEAR + Coy I
SLED cear-——( @ >
GREASE
EM-50L.
©
lan
SLED
MOTOR
+PLUS MARK +PLUS MARK
SPINOLE
iS SPINOLE/SLED MOTOR PW.B
SS
ae

CD MECHANISM ADJUSTMENTS
i. CD MECHANISM
(a) Replacement of the spindle motor agree Sapte
e First, prepare the new turntable (701-1 ) and new special WASHER ——+ agsout ABOUT 4 ___ BOND
washer
(
701-4,701-5
)
for
replacement.
7
eam
ra
The removed turntable will be deformed by the heat of
the
soldering
iron,
and
cannot
be
reused.
O
Ox
@ Prepare dial-type calipers.
(1) The attached bonding material can be dissolved by using
a 60W soldering iron to heat the shaft at the upper part
of the turntable for about one minute.
(2)
The
turntable
can
then
be
removed
from
the
shaft
by
very
g
z
carefully applying force upward at the center of the lower surface
of the turntable.
(3) Remove the two screws ( 701-2 ) and remove the spindle motor
(701-6).
(4) Attach the special washer ( 701-4, 701-5 ) to the spindle motor.
(5) Clean the spindle motor’s shaft.
To clean them, use a soft cloth soaked in isopropyl alcohol. (A
(6) Apply a small amount of a mixture of the “Three Bond 2001”
and “2015F” bonding materials to the motor’s shaft. 703
(7) Install the turntable as shown in the figure.
(8) Secure the turntable by pressing gently.
Be sure to wipe away (by using a piece of cloth, or similar
material)
any
bonding
material
coming
out
of
the
hole.
~
SE
ae)
(b) Replacing the pick-up
(1) Insert the pick-up rail (703 ) into the base chassis. ( 701-3 )
(2) If the lach of the base chassis ( 701-3) are missing when
the pick-up rails have been installed, first wipe the
tips of the rail with alcohol.
(3) After the pick-up has been replaced, apply grease
(FLOIL G-474B) to the [F=2==] sections.
(4) The pick-up P.W.Board pattern is “shorted“, as shown
in the figure, so that the new pick-up will not be
susceptible to the effects of static.
(5)
Set
the
pattern
to
“open“
after
the
pick-up
has
been
replaced.
(BE
SURE
AT
THIS
TIME,
NOT
TO
TOUCH
ANY
OTHER
PART.)
(SHORT) (OPEN)
-~12-

CD PLAYER ADJUSTMENTS
a. PREPARATIONS
(a) Measuring instruments, tools and filter
(1) Test disc.: YEDS 18 (SONY) or etc.
(2) Oscilloscope : SS5711 (10 MHz or dual-phenomenon)
or Memoryscope : DSS6521 (Storagescope)
(3) Screwdrivers (non-metallic) for adjustments
b. PARTS LOCATION
TRACKING BALANCE EYE PATTERN
OSCILLOSCOPE
CN101 fates
TRACKING
TP4 (vey
1P3 (TE) BALANCE
TP2(FE)
TP1 (RF)
c. TEST CABLES CONNECTION
Ass'y CONNECTOR (10P)
(614 279 4494)
Ass'y
CONNECTOR,
FPC
(11P)
@(645
009
0752)
PRE - AMP
Assy CONNECTOR (14P)
(614 275 5099)
NX
)
\ AEC
Ass'y CONNECTOR(10P)
(614 275 5105)
Ass'y
CONNECTOR,
FPC(9P)
(645
016
7904)
Assy CONNECTOR (6P)
(614 275 5129)
p
§ SPINDLE / SLED
MOTOR PWB
ont
PICK - UP
243 =
Ass'y
CONNECTOR,
FPC
(13P)
(614
275
5112)

CD PLAYER ADJUSTMENTS
d. ADJUSTMENTS
Adjustment
Measuring
input
Output
Adjustment
Adjustment
value
Item
instrument
jconnection|
connection
location
(a)
Tracking
,
TP
327E
Waveform
symmetry
balance
Oscilloscope
TP
4:VC
VR1i01
A=B
(b)
Checking
Check
be
sure
that
the
"eye”
the
"eye"
Oscilloscope
pattern
is
at
the
center
of
the
tt
y
P
waveform
and
that
the
diamond
panei
shape
is
clearly
defined
(a) Tracking balance adjustment
(1) Within one second after pressing CLOCK
& REV MODE switches at the same time, press the
MEMORY switch. (D,@)
( Service mode : TRACKING BALANCE )
(2)
Connect
an
oscilloscope
to
TP3
(TE)
and
TP4
(VC).
_ (3) Set the test disc. (DISC 1)
(4) PLAY / PAUSE switch push ON”.
(5) Adjust VR101 so that the oscilloscope’s waveform is
symmetrical,
as
shown
in
the
illustration.
SSS
PLAY.
(6)
To
cancel
service
mode,
disconnect
the
power
cord’s
plug
I
|
O
—
EAE
DURE
eB _ CQ Oo |
CLOCK
(@)
Po
REV
MODE
(®)
MEMORY ot! oe
+ ©
OPEN/CLOSE
from the electrical outlet.
ae
FANE
BRE: mV/div-
RF
TE
(b)
Checking
the
”eye”
pattern
OSCILLOSCOPE
(1) Switch "ON" the POWER.
(2)
Connect
an
oscilloscope
to
TP1
(RF)
and
TP4
(VC).
(3) Load the test disc.
: WN 'o's‘n'eie'e we!
(5) Check to be sure that the “ eye ” pattern is at the center of PN om OPENING EXPANDED
waveform and that the diamond shape is clearly defined.
(6) Press the STOP button.
(7) Switch “OFF” the POWER.
haem by
~14-

TAPE DECK ADJUSTMENTS
. Measuring : Adjust Adjust
ex Sp re HEAD AZIMUTH
(a) HEAD AZIMUTH AC-voltmeter EAKER TER AL SCREW Max.
(FWD / REVERSE)
(b) MOTOR SPEED MTT-111 FREQUENCY CN303 (1 &2)
SPEAKER TERMINAL VR302 3,000 H
(NORMAL) (3,000 Hz) COUNTER ‘ “OPEN”
TCW-211 FREQUENCY CN303 (1 &2
(c) MOTOR SPEED Q SPEAKER TERMINAL VR301 3,000 Hz : ( J )
(HIGH ) (1,500 Hz) COUNTER SHORT
a. HEAD REPLACEMENT AND AZIMUTH ADJUSTMENT
VTT738 etc.
(10 kHz)
(a) Head replacement
(1) After replacement, demagnetize the heads by using E. & R/P HEAD
a degausser. :
(2) Be sure to clean the heads before attempting to
make any adjustments.
(3) Be sure both channels (1 and 2) are the same level
(Using a dual-channel oscilloscope).
ee
sy
Pe
WHITE
(4)
All
wiring
should
be
returned
to
the
original
position
BLUE
GREEN
after
work
is
completed.
BLACK
ORANGE
REO
YELLOW
RED YELLOW
BLACK RANGE
BLUE
WHITE
(b) Head azimuth
(1) Load a test tape (VTT-738, etc.: 10 kHz) for azimuth
; adjustment.
(2) Press the Forward PLAY button (normal playback).
(3) Use a flat-tip ( - ) screwdriver to turn the screw for
normal azimuth adjustment so that the left and right
outputs are maximized at the same phase during
normal playback.
(4) Press the Reverse mode button.
(5) Play the tape in the reverse mode.
(8) Use a flat-to- ( - ) screwdriver to turn the screw for a]
reverse azimuth adjustment so that the left and right REVERSE a
outputs are maximized at the same phase during NORMAL
reverse playback.
(7) Press the STOP button.
® After making the adjustment, secure the azimuth
: adjustment screw by applying screw lock (TB-1401B).

TAPE DECK ADJUSTMENTS
b.
MOTOR
REPLACEMENT
AND
SPEED
ADJUSTMENT
(a) Motor replacement
(b) Motor speed
e NORMAL SPEED
(1) Insert the test tape (MTT-111, etc. 3,000 Hz) .
(2) Press PLAY button.
(3)
Adjust
VR302
so
that
the
frequency
counter
shows
a
reading
of
3,000Hz.
©
(4) Press STOP button.
VR3
eer
eee
HIGH
SPEED
(1)
Insert
the
test
tape
(TCW-211,
etc.
1,500
Hz
optional)
.
his
VR302
(2)
Press
PLAY
button.
faye
2
ia
NORMAL
SPEED
(3)
Set
to
the
high-speed
condition.
omen
CN303
(4)
Short-circuit
test
points
socket
CN303
(1
&
2).
Test
POINT
(5)
Adjust
VR301
so
that
the
frequency
counter
shows
a
reading
of
3,000Hz.
(6)
Press
STOP
button.
(7)
After
the
completion
of
the
adjustment,
remove
the
short-
circuit
between
socket
CN303
(1
&
2).
c.
CHECKING
THE
MECHANISM
TORQUES
®
Clean
the
head,
capstan
and
pinch
roller
before
making
any
measurement.
e
Check
during
both
normal
and
reverse
playback.
PLAY:
TW-2111A
(FWD)
Drive-power
cassette
Cassette
for
PLAY:
TW-2111A
(FWD
‘
PLAY:
TW-2121A
(REV)
PLAY:
TW
ee
TW-2412
(FWD)
een
E.FWD/REW:TW-2231
TW-2422
(REV)
PLAY
30~
60
gr.cm
2.0~
5.0
gr.cm
=(6=

AMPLIFIER ADJUSTMENTS
® Make the following adjustments after first cleaning the head assembly and checking the adjustment of the head azimuth.
CN373 TAPE OUT
PL
BE
VR351
ff VR373
REC (L-CH)
(fa VR371
PLAY(L-CH)
VR3746
BIAS(L-CH)
i VR384
BIAS(R-CH)
VR383
REC (R-CH) itis
VR381
PLAY (R- CH) (2
ice ; . Test Tape DOLBY Measuring Input Output Adjust Adjust
justment Item Pe | NR SW. | Instrument | Connection connection location value
TCC-130
VR371 (L-CH
(a) Playback output (DOLBY AC-Voltmeter TAPE OUT ( } 300 mV
VR372 (R-CH)
TAPE)
(b) Recording/ AC-224 AC-Voltmeter VIDEO TAPE OUT VR373 (L-CH) 300mV
Playback gain (NORMAL) AF-Oscillator | - 10 dB, 1kHz VR383 (R-CH) +0.5 dB
VIDEO at 1 kHz
- 30 dB, 1 kHz, and 10 kHZ
10 kHz 0+ 1.0d8
AC-224 AC-Voltmeter
(NORMAL) AF-Oscillator
(c) Recording / Playback
frequency response
VR374 (L-CH)
VR384 (R-CH)
TAPE OUT
a. ADJUSTMENTS
(a) Playback output adjustment (c) Recording / Playback response adjustment’
Dolby NR switch : OFF Input signal : - 30 dB, 1 kHz, 10 kHz
(1) Play the test tape and adjust VR371 (L-CH) and VR372 Tape to be used : NORMAL (AC-224, etc.)
(R-CH) so that playback output becomes 300 mV. Dolby NR switch : ON
(1) Introduce input signals to the VIDEO terminals.
(b) Recording / Playback frequency gain adjustment (2) With the unit in the REC. mode.
input signal : - 10 dB, 1 kHz Record these input signals (1 kHz > 10 kHz =>
Tape to be used : NORMAL (AC-224, etc.) 1 kHz — 10 kHz).
(1) Introduce input signals to the VIDEO terminals, and, (3) Press the REWIND bution and rewind tape
with the unit in the REC. PAUSE mode, adjustment input to the beginning of the recording just made.
level for 300 mV out. (4) Press the PLAY button.
(2)
Record
the
input
signal.
(5)
Adjust
VR374
(L-CH)
and
VR384
(R-CH)
so
that
the
(3) Press the REWIND button and rewind tape to the 10 kHz and 1 kHz and output level differences
beginning of the recording just made. become 0 +1 dB.
(4) Press the PLAY button. (6) Repeat steps (1) to (5).
(5) Adjust VR373 (L-CH) and VR383 (R-CH)
so that the recording and playback
output level differences become 300 mV 0.5 cB.
(6) Repeat steps (1) to (5).
-17-