Akai GX-646 User manual

AKAI SAKAI. ©
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STEREO TAPE DECK
movi.GX-646

STEREO TAPE DECK
moveLG X-64:6
THIS MANUAL IS ALSO APPLICABLE TO BLACK PANEL MODELS
SECTION 1 SERVICEMANUAL ................... 3
SECTION.2: . -PAK IS LIST y-s50Fascaea esa eae a8 33
SECTION 3. SCHEMATIC DIAGRAM ................ 48

SAFETY
INSTRUCTIONS
A
ee
ee
eee
ee
SAFETY
CHECK
AFTER
SERVICING
Confirm
the
specified
insulation
resistance
between
power
cord
plug
prongs
and
externally
exposed
parts
of
the
set
is
greater
than
10
Mohms,
but
for
equipment
with
external
antenna
terminals
(tuner,
receiver,
etc.)
and
is
intended
for
or
[A],
specified
insulation
resistance
should
be
more
than
2.2
Mohms
(ground
terminals,
microphone
jacks,
headphone
jacks.
line-in-out
jacks
etc.)
PRECAUTIONS
DURING
SERVICING
1.
Parts
identified
by
the
A\
symbol
parts
are
critical
for
safety.
Replace
only
with
parts
number
specified.
2.
In
addition
to
safety,
other
parts
and
assemblies
are
specified
for
conformance
with
such
regulations
as
those
applying
to
spurious
radiation.
These
must
also
be
replaced
only
with
specified
replacements.
Examples:
RF
converters,
tuner
units,
antenna
selector
switches,
RF
cables,
noise
blocking
capacitors,
noise
blocking
filters,
etc.
3.
Use
specified
internal
wiring.
Note
especially
:
1)
Wires
covered
with
PVC
tubing
2)
Double
insulated
wires
3)
High
voltage
leads
4,
Use
specified
insulating
materials
for
hazardous
live
parts.
Note
especially:
1)
Insulation
Tape
2)
PVC
tubing
3)
Spacers
(Insulating
Barriers)
4)
Insulation
sheets
for
transistors.
5.
When
replacing
AC
primary
side
components
(transformers,
power
cords,
noise
blocking
capacitors,
etc.),
wrap
ends
of
wires
securely
about
the
terminals
before
soldering.
c>
—
Observe
that
wires
do
not
contact
heat
producing
parts
(heatsinks,
oxide
metal
film
resistors,
fusible
resistors,
etc.).
Check
that
replaced
wires
do
not
contact
sharp
edged
or
pointed
parts.
Also
check
areas
surrounding
repaired
locations.
Use
care
that
foreign
objects
(screws,
solder
droplets,
etc.)
do
not
remain
inside
the
set.
cde aera ee

SECTION 1
SERVICE MANUAL
TABLE OF CONTENTS
T. sSPECIBICA TIONS #9 355.0250 025 0) Hise Gis ae a a W are bei eieate: bis hat & Wha ta ia A B98 coe Dae eae 8 480s 4
Il. DISMANTLING OF UNIT... 1.0... 00. c ec eee ene vai tbs ph Biel he awe ah eae dncahyer ave! S78, wi Hone a tas 5
TID. @CONTROUES | 5.05.50 orsi estes ta 0255 sacs Mia a ews Bele Bb Was Ring ees ie ta Talia) Ola) ae alae HE aaa 6
IV. PRINCIPAL PARTS LOCATION ......... 0. cc cece cece cere ener renee wren renees 7
V. VOLTAGE AND CYCLE CONVERSION 1.0.0... 0c cece cece ence renee ener e ee eeenoee 8
1. VOLTAGE CONVERSION 2.0... ccc cee ce eee eee te eee ene e ee eee eee eeeenes 8
2, CYCLE CONVERSION 2.0... ccc cece cere reer teen e neers ee sees seeeeeereees 8
VI. MECHANISM ADJUSTMENT ... 1... cic cc cc ce eee tenet eee eee teen e nee 9
1. GUIDE ROLLER LOOSE PLAY ADJUSTMENT . 1.0... ccc ccc cece eee eens 9
2. TENSION MICRO SWITCH POSITION ADJUSTMENT ........ 0. ee eee eee e cree erevees 9
3, ROLLER BLOCK- HEIGHT ADJUSTMENT 03. c\.a Casas sb cadau erated aeaeinls oe eee 9
4. REEL TABLE HEIGHT ADJUSTMENT... 1... ee ee eee eee eee aes 10
5. CAPSTAN SHAFT LOOSE PLAY ADJUSTMENT ....... 0.0 cece ee eee eee entre ene 10
6. BRAKE BAND POSITION ADJUSTMENT AND BRAKE TENSION ADJUSTMENT ........... 11
7. PINCH ROLLER POSITION ADJUSTMENT «0... ccc ccc eee cc ee eee nee te eens 12
8. PAUSE PLUNGER POSITION ADJUSTMENT ...... ccc cece cee teen een teen neee 12
9. PINCH ROLLER PRESSURE ADJUSTMENT .... 0... ccc eee cc eee eee e entrees 12
10. TAPE SPEED ADJUSTMENT 20... ccc cee eee ee ee een e eee ennnees 13
VII. HEAD ADJUSTMENT .. 0... cc ce cc etre eet eee eee renee ere neee 14
VII. AMPLIFIER ADJUSTMENT .. 10... ce eee eee ee eee een ee tener eres 16
IX. DC RESISTANCE OF VARIOUS COILS 2.0... ... ccc ccc ccc ee etree eee e eee tenees 19
X. CLASSIFICATION OF VARIOUS P.C BOARDS .. 0.0... ccc cee eee eee ene reenes 20
1. P.C BOARD TITLES AND IDENTIFICATION NUMBERS ........ 0. cee cece eee teres 20
2. COMPOSITION OF VARIOUS P.C BOARDS ... 0... cee ee ce ee eee ee eee nees 21
For basic adjustments, measuring methods, and operating principles, refer to GENERAL TECHNICAL MANUAL.

I. SPECIFICATIONS
TRACK SYSTEM 4 Track 2 Channel Stereo System
REEL CAPACITY Up to 10” reel
HEADS GX head for Recording x 2
GX head for Playback x 2
Erase head x 2
MOTORS AC Servo motor for capstan drive x 1
AC Eddy current motor for reel drive x 2
TAPE SPEED 19 cm/s + 0.8% (7-1/2 ips.)
9.5 cm/s + 1.0% (3-3/4 ips.)
WOW & FLUTTER Less than 0.03% WRMS, 0.07% DIN 45500 at 19 cm/s
Less than 0.04% WRMS, 0.09% DIN 45500 at 9.5 cm/s
TAPE WINDING TIME 75 sec. using 360 m (1,200 ft.) Tape
FREQUENCY RESPONSE 25 to 33,000 Hz + 3 dB at 19 cm/s
25 to 26,000 Hz + 3 dB (0 VU)
25 to 25,000 Hz + 3 dB at 9.5 cm/s
25 to 15,000 Hz + 3 dB (0 VU)
SIGNAL TO NOISE RATIO Better than 65 dB at 19 cm/s DIN 45500
HARMONIC DISTORTION Less than 0.4% at 19 cm/s
INPUT MIC: 0.25 mV (input impedance 5.0 kohms)
Required microphone impedance: 600 ohms
Line: 70 mV (input impedance 100 kohms)
OUTPUT Line: 0.775 VatO VU
Required load impedance: more than 20 kohms
Phone: 100 mV/8 ohms at 0 VU
DIN Input: 2 mV (input impedance 10 kohms)
Output: 0.3 V
Required load impedance: more than 20 kohms
POWER REQUIREMENTS 100 V, 50/60 Hz for Japan
120 V, 60 Hz for USA & Canada
220 V, 50 Hz for Europe except UK
240 V, 50 Hz for UK & Australia
110 V/120 V/220 V/240 V, 50/60 Hz switchable for the
other countries.
POWER CONSUMPTION J75W
C,A 120 W
. U70W
DIMENTIONS 440 (W) x 483 (H) x 256 (D) mm
(17.3 x 19.0 x 10.1 inches)
WEIGHT 21 kg (46.4 Ibs)
* For improvement purposes, specifications and design are subject to change without notice.

li. DISMANTLING OF UNIT
In case of trouble, etc. necessitating dismantling, please dismantle in the order shown in the photographs. Reassemble in
reverse order.
1 SIDE BOARD 6
SCREWS SCREWS & CONTROL KNOBS
2 7
a:
SCREWS & KNOBS ] PINCH ROLLER
HEAD COVER BASE
SCREWS
8 MECHA ae BLOCK |
UPPER COVER SEGENS
AMP PANEL BLOCK |
4
FOOT q
BOTTOM PLATE
SCREWS
BACK BOARD SCREWS

il. CONTROLS
Fig. 1 Controls
SUPPLY REEL TABLE 19. REAL TIME COUNTER and RESET BUTTON
1.
2. BUILT-IN REEL RETAINER (Left) 20. RIGHT TENSION ARM (SENSING PIN)
3. PITCH CONTROL 21. GUIDE ROLLER (Right)
4. LEFT TENSION ARM (SENSING PIN) 22. HEAD COVER
5. GUIDE ROLLER (Left) 23. PINCH ROLLER
6. RECORDING MUTE SWITCH 24. BIAS ADJUSTMENT VOLUME
7. REELSIZE SELECTOR 25. OPERATING BUTTONS
8. POWER SWITCH ; 26. MEMORY MARKER
9. REVERSE SELECTOR 27. LINE INPUT CONTROLS
10, VU METER (Right) 28. MICROPHONE INPUT CONTROLS
11. VU METER (Left) 29. MICROPHONE JACKS (Left/Light)
12. HEADPHONE JACK 30. RECORDING MODE SWITCH
13, OUTPUT LEVEL CONTROL 31. TAPE SELECTOR
14, TIMER START 32. REMOTE CONTROL JACK .
15. MONITOR SWITCH 33. LINE IN JACKS
16. TAPE SPEED SELECTOR 34. ACCORD
17, TAKE-UP REEL TABLE 35. LINE OUT JACKS
18.
BUILT-IN
REEL
RETAINER
(Right)
36.
DIN
JACK
(Some
models
do
not
have
this
facility}

IV. PRINCIPAL PARTS LOCATION
BRAKE MICRO SWITCH
Sw906
BRAKE PLUNGER
PLAY
PLUNGER
SL904
PITCH
CONT
AOE
VOLUME
PAUSE PLUNGER SL9OI REAL TIME COUNTER
TENSION ARM (R)
TENSION ARM(L)
REC MUTE SWITCH SW904
REEL
SIZE
SWITCH
SW903
HEAD
BLOCK
REVERSE SELECTOR SWITCH
POWER SWITCH SW90I OPERATION BLOCK
:
t
ae
ee
an
MIC
REC
LEVEL
VU METER|
LINE VOLUME
L
PHONES JACK
R
OUTPUT
LEVEL,
CONTROL
_lmic
JACK
VOLUME
TIMER
START
SWITCH
BIAS
ADJUSTMENT
VOLUME
MONITOR SWITCH
Lt
REC MODE SWITCH -
TAPE SELECTOR SWITCH
TAPE SPEED: SWITCH
Fig. 2 Front View
TIMER PCB
TIOl4C5010
REMOCON
JACK
USE PCB TH-2040
SYSCON PCB TH-IOI5
CAPSTAN MOTOR
OPERATION
PCB{A)
M903
SCM-200
TH-2041
OPERATION PCB(B).
TH- 2042
PRE AMP_PCB
TIOOSA5IOA
IN OUT
Fig.3 Rear View

V. VOLTAGE AND CYCLE CONVERSION
=
°
FUSE FI
VOLTAGE SE
fer
LECTOR
200V
AREA
250V
1.25A
I[OOV AREA 250V 2.5A
D
POWER CORD
CYCLE CHANGE SWITCH [ites
swi
_60Hz—50Hz
Fig.4 Voltage Conversion (U/T Model) and Cycle Conversion (U/T, JPN Model)
1. VOLTAGE CONVERSION (Refer to Fig. 4)
1)
2)
JPN Model (100V, 50/60 Hz)
CSA, AAL Model (120V, 60 Hz)
CEE Model (220V, 50 Hz)
UK, SAA Model (240V, 50 Hz)
Voltage can not be switched.
U/T Model (110/120/220/240V, 50/60 Hz)
Remove the back board and find out the voltage
selector and Fuse P.C Board on the upper por-
tion of the machine. Change the position of
voltage selector plugs so that the voltage to be
used coincides with the voltage shown through
the opening of voltage selector plug.
The rating of fuse (F1) differs depending on the
voltage to be used. Change the fuse according to
the specified rating shown below.
110/120 V Area 250V2.5A
220/240 V Area 250V1.25A
2. CYCLE CONVERSION (Refer to Fig. 4)
Cycle can be converted only in U/T, JPN Model.
Remove the back board and select the position of
switch located in the recess at right portion of Syscon
P.C Board to correspond to the frequency of power
to bé used. Move the switch to the right for 50 Hz
and to the left for the 60 Hz.

Vi.
ADJUSTING WASHER
(U TYPE)
ADJUSTING WASHER
(U TYPE)
.GUIDE ROLLER LOOSE PLAY
ADJUSTMENT (Refer to Fig. 5)
Adjust the stopper (roller pulley on the right) screw
(d) so that the loose play gap is approximately
0.1 mm when the guide roller is moved as indicated
by arrow mark in Fig. 5.
. TENSION MICRO SWITCH POSITION
ADJUSTMENT (Refer to Fig. 5)
Adjust the screws (e) so that the gap between the arm
cam and the micro switch is approximately 0.5 to
0.8 mm. Check the the micro switch works and that
the arm lock smoothly disengages.
TAPE GUIDE
GUIDE ROLLER
M ECHANISM ADJUSTMENT
al
ae
TENSION MICRO SWITCH
Fig. 5 Roller Block
3.
ROLLER
BLOCK
HEIGHT
ADJUSTMENT
(Refer to Fig. 5)
Use
the
U
type
adjusting
washers
for
screws
(a),
(b),
and
(c)
to
adjust
the
roller
block
height:
the
distance
between
the
tape
guide
center
to
the
chassis
board
should be 43 mm.
NOTE:Steps
1
and
3
also
apply
to
the
right
guide
roller.

CAPSTAN MOTOR
SCM-200 X Of to 0.2mm
FIXATION NUT
REEL TABLE
FIXING SCREWS
Por ee mentor
ADJUSTMENT SCREW
WL
Fig. 7
Fig. 6
4,.REEL
TABLE
HEIGHT
ADJUSTMENT
5.
CAPSTAN
SHAFT
LOOSE
PLAY
(Refer
to
Fig.
6)
ADJUSTMENT
(Refer
to
Fig.
7)
1)
Temporarily
screw
in
the
fixing
screws
leaving
a
Adjust
by
turning
Adjustment
Screw
to
obtain
a
0.1
gap
of
15
mm
between
the
reel
table
and
the
to
0.2
mm
degree
of
loose
play
when
the
capstan
chassis
board.
shaft
is
moved
as
indicated
by
the
arrow
mark.
2)
Run
the
tape
and
adjust
the
height
of
the
reel
Tighten
fixation
nut
to
maintain
optimum
adjusted
table
so
that
the
tape
is
taken
up
in
the
center
of
condition.
the reel. Tighten fixing screws.
Adjust the height of the right reel table at fast
forward, of the left reel table at rewind.
10

BRAKE MICRO
SWITCH
A {tof.5mm °
<— S
pie
nT "
fel Jo) BRAKE PLUNGER
Fig. 8
5609 +209
6. BRAKE BAND POSITION ADJUSTMENT
AND BRAKE TENSION ADJUSTMENT
(Refer to Figs. 8,9, 10)
1) Adjust the screws (a) and (a’) so that the gap A
between the brake lever and the rubber is 1 to
1.5 mm.
2) Work the brake plunger to check that the brake
band is not slanted.
3) With the machine stopped, adjust the position of
the spring so that a brake tention of 560 + 20 g is
obtained on each brake.
4) By working the brake plunger with a finger,
adjust the position of the micro switch screw (c)
so that the gap between the brake lever and the
Micro switch body is 0.2 to 0.3 mm.
Fig. 9
11

PINCH ROLLER
PLUNGER
PAUSE PLUNGER
CLAMP JOINT
P LEVER JOINT
Fig. 11
. PINCH ROLLER POSITION ADJUSTMENT
(Refer to Fig. 11)
At the play mode, the gap between the clamp joint
and the P lever joint should be 0.3 to 0.5 mm. Adjust
the pinch roller plunger position with screws (a).
. PAUSE PLUNGER POSITION
ADJUSTMENT (Refer to Figs. 11, 12)
At the pause mode, the gap between the capstan and
the pinch roller should be 0.3 to 0.5 mm. Adjust the
pause plunger position with screws (b).
Fig. 12
9. PINCH ROLLER PRESSURE ADJUSTMENT
Connect a 2 kg spring gauge to the pinch roller fixing
screws. Pull down the pinch roller and then let it
slowly move back. Check that the spring gauge reads
1.2 kg + 200 g at the moment the pinch roller touch-
es the capstan and starts rolling.
It is reads otherwise, replace the P spring (See Fig.
12)

VR2 20K VRI SOK
(7-1/2in) (3-3/4 in)
SYSCON PCB
TH-1015
Fig. 13
10.TAPE
SPEED
ADJUSTMENT
(Refer
to
Fig.
13)
Set
the
Tape
Speed
Switch
to
7-1/2
ips.
and
playback
the
1,000
Hz,
7-1/2
Test
Tape.
Connect
a
frequency
counter
to
LINE
OUT
and
adjust
VR2
20
kB
until
the
counter
reads,
1,000
Hz
+
0.5%.
Next,
set
the
Tape
Speed
Switch
to
3-3/4
ips.
and
adjust
VR1
50
kB
until
the
frequency
counter
reads
500
Hz
+
0.5%.

Vil. HEAD ADJUSTMENT
TAPE GUIDE HEIGHT ADJUSTMENT NUT REV
nol) BACK RECORDING ERASE
D
HEAD - HEAD
=
d| eae
R4-24] E4-245
mG | aes =
“Al _——— ——<—ry r=
a S|
we
ERASE RECORDING PLAYBACK
HEAD HEAD HEAD TAPE GUIDE
E4-245 R4-241 P4-500

ADJUSTMENT TEST TAPE MODE
ITEM SUPPLY SIGNAL
ADJUSTMENT
POINT
REMARKS
Tape Guide
=
Head Height
Confirmation
FWD Playback
Head Height
Optional
FWD
Optional
Tape Guide
Height
Adjustment
Nut
1
1) Adjust so that tape travels
smoothly and does not twist.
2) Do not thread tape over tension
arm.
FWD Recording ‘ ms
Head Height
(a) (b)
Upper edges of Left Ch. head core
and tape are the same height.
Upper edge of Left Ch. head core
is 0.1 mm higher than upper edge
of tape
Upper edges of Left Ch. head core
and tape are the same height.
FWD Playback 8,000 Hz
Head Azimuth 3-3/4 ips
Alignment Test Tape
Maximum output, both channels.
FWD Playback
Head Angle
Alignment
8,000 Hz
3-3/4 ips
Test Tape
FWD Recording Maxell UD
Head Azimuth 15,000 Hz
—20 dBm
FWD Recording Maxell UD
Head Angle 15,000 Hz
Alignment —20 dBm
NOTES: 1. As perfect head adjustments are vital to tape
deck performance, be sure that these adjust-
ments are carried out properly.
2. Be careful not to use a magnetized driver or
other magnetized tools in the vicinity of
the heads.
3. Use only new tape as level variation is likely
to occur when using old tape.
4, Demagnetize heads with head demagnetizer
before and after head adjustment.
5. Set tape speed to 7-1/2 ips.
6. Set Tape Selector Switch to NORMAL Posi-
tion.
7, Adjustments outlined in Fig. 15 are only for
FWD side heads. However, adjustments for
REV side heads are exactly the same.
Adjust head gap surface so that
there is no change in output level
when tension is applied to the
supply reel side.
Maximum output, both channels.
See NOTE 6.
Adjust head gap surface so that
there is no change in output level
when tension is applied to the
supply reel side.
Fig. 15
15

Vil.
AMPLIFIER
ADJUSTMENT
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SVId
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YSLAWLIOA
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ig 16 Pre Amp P.C Board.T1009A510A
16

REC HEAD
AUDIO
OSCILLATOR
(23.2KHz)
AC VOLT METER
Fig.
17
Rec
Peaking
Adjustment
Instrument
Connection
AC VOLT METER
(LEFT)
REC HEAD
AC VOLT METER
(RIGHT)
Fig. 18 Rec Peaking Adjustment
[
ADJUSTMENT
|
TEST
TAPE
ADJUSTMENT
|
|
oe
ITEM
SUPPLY
SIGNAL
|MOPF|
point
RESELL
REMORS:
FWD
Playback
|
700
Hz
7-1/2
i
Vs
|
040.5
4B
zal
~|
aybac
z
7-1/2
ips.
+0.5
dBm
:
Level
0
VU
Test
Tape
eevee
VEO
SOES
(0.775V)
|
‘
“|
REV
Playback
|
700Hz7-1/2ips.
|
pey
|
R650
ia.
|
0
+0.5
dBm
|
Level
0
VU
Test
Tape
|
_(0.775V)
|
|
Set
TAPE
SELECTOR
93.2
kHz
from
Maximum
AC
|
to
“NORMAL”
3
REC
Peaking
es
Oscillator
REC
VLi
1
mH
Voltmeter
|
Tape
Speed
3-3/4
ips.
indication
See
NOTE
6,
7,
9
and
ai
|
|
Figs.
16,
17,
18.
Set
TAPE
SELECTOR
to “NORMAL”
4
BIAS
OSC
REC
TI
100
0.5
kHz
|
18Pe
Speed
7-1/2
ips.
Connect a Frequency
Counter between TP
he
[and
GND.
Fig.
16.
|
oe
——
—
17

—r eae
ADJUSTMENT TEST TAPE ADJUSTMENT
oe ITEM suPPLY SIGNAL |MOPE) pont RESUEE roecaaeie
Set TAPE SELECTOR
to “NORMAL”
BIAS Tape Speed 7-1/2 ips.
: Current REY MRS 20KR Peo my Connect a AC Volt-
meter between TP and
GND Fig. 16.
FWD NORMAL Blank
f FWD/ 0+0.5 dBm
6 Recording Tape 1,000 Hz VR2 20 kB
Level 0 dBm Recordin a (0.775)
i79 g
REV NORMAL Blank
7 Recording Tape 1,000 Hz — vRi20Ke | ° eu
Level 0 dBm Recording :
NORMAL
|
NORMAL
Blank
|
Position
FWD
|
Tape
1.5kHz,
|
FWD/
bee
beer
,-
|
Tepe
Speed
3
SUID
8 VCl 15 kHz Recheck Recording
Frequency 15 kHz —20 dBm | REC
: flat Level.
Response Hes Recording
NORMAL NORMAL Blank :
Position
REV
Tape
1.5
kHz,
REV/
EEE,
depo
Sreed
pies
se
9 VC2 15 kHz Recheck Recording
Frequency 15 kHz —20 dBm | REC
‘ flat Level.
Le Response Recording
cue | BE Blank Tape | FWD, 1.5kHz, | Tape Speed 3-3/4 ips.
10 jens 1.5 kHz, 20kHz | REV/| VR410kB 20kHz | Recheck Recording
(3-3/4 ips) —20 dBm recording | REC flat Level.
Sa EE Blank Tape | FWD, 1.5kHz, | Tape Speed 7-1/2 ips.
11 Rewer 1.5 kHz, 25kHz | REV/| VR930kB 25kHz | Recheck Recording
(7-1/2 ips) —20 dBm Recording] REC flat Level.
FWD 1,000 Hz 0 dBm | FWD/ | NORMAL: Less than 0.5%
12
Distortion
Recordin
REC
EE
:
Less
than
0.4%
Confirmation ae L See NOTE 8.
REV NORMAL: Less than 0.5%
13
Distortion
cae
ye
j
om
ee
EE
:
Less
than0.4%
Confirmation ene See NOTE 8.
oe hee ee 0 VU Set MONITOR Switch
14
Sensitivity
from
an
STOP
VR8
1
kB
Ogee
oe
bi
5
; indication to “SOURCE
(JPN) | __ Oscillator
NOTES: 1. Output Level Control should be at maxi- 6. Stop Recording bias oscillator while mak-
mum. ing Rec Peaking adjustment (Refer to Fig.
2. Except for Steps 3, 8, 9 and 10, set Tape 16).
Speed to 7-1/2 ips. 7. When 23.2 kHz indicates the peak, check
3. Except for Steps 10 to 12 and 13, set Tape and ensure that the AC Voltmeter show 16
Selector Switch to NORMAL Position. dB of increase when 15 kHz of input is fed
4. Set Bias Adjustment Volume to center rather than when 1 kHz is fed.
position. 8. If it does not comply with the specifica-
5. Use the following open measuring tapes: tions repeat Steps 6 to 10 and 11, and re-
NORMAL Tape: Maxell UD adjust.
EE Tape : Maxell XLII 9. Unless the core is moved intentionally this
TDK SA adjustment is not necessary.
18

IX.
DC
RESISTANCE
OF
VARIOUS
COILS
PART
DESIGNATION
DC
RESISTANCE
i
Between
BLU-RED:
110
ohms
Main
Motor
SCM-200
Between
YLW-BRN:
170
ohms
Pick-up
Coil:
665
ohms
_|
Between
BLU-RED:
30
ohms
cco
cies
Between
YLW-BRN:
157
ohms
Pinch
Roller
Plunger
1664PLT1
600
ohms
+
10%
i]
eed
a
1240PLT1
Z
600
ohms
+
10%
REV
Plunger
Pause
Plunger
0730FLT2
im
600
ohms
+
10%
|
Relay
MY4-02-US-L
650
ohms
+
15%
|
Relay
FBR211BD024M
|
1,280
ohms
+
10%
|
Relay
G2KU
1,000
ohms
+
10%
a
Relay
LAB2NS
1,750
ohms
+
10%
_|
Erase
Head
E4-245
3.1
ohms
Recording
Head
R4-241
|
5.9
ohms
z
Playback
Head
P4-500
407
ohms
+
5%
_|