Sharp WQ-T37OA User manual

SHARI= SERVICE MANUAL
SYOC7WQT370AG
WQ-T37OA( GY)
In the interests of user-safetythe set should be restored to its original
condition and only parts identical to those specified be used.
/
INDEX TO CONTENTS
Page
SPEC,F,CAT,ONS ..................................................................*
STR,NG,,+G OF D,AL CORD
.........................................................
NAMES OF PARTS .................................................................
DISASSEMBLY
.....................................................................
REMOVING A ND REINSTALLING THE MAIN PARTS
.................................
-5
ADJUSTMENT ................................................................
..6.7
EXPLODE,, VIEW
.............................................................
.fj-,,-J
BLOCK DIAGRAM
..........................................................
SCHEMATIC DIAGRAM/WIRING SIDE OF P.W.BOARD
..........................
..l. ,*
..13~2 0
REPLACEMENT PARTS LIST.
..................................................
.2l-25
SHARP CORPORATION

7
FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE
REFER TO THE OPERATION MANUAL.
General
Power source:
Output power:
Speakers:
Input impedance:
Load impedance:
Dimensions:
Weight:
1. Turn tt
-
le drum fully in the drrectron (8, shown in Fig. 2-2 and
stretch its cord over the parts in the numerical order.
2. Then turn the tuning control shaft fully in the direction @
shown in Fig. 2-2 and fix its pointer as shown in Fig. 2-1.
SPECIFICATIONS
AC 230 - 240 V, 50 Hz
DC 12 V [“D” size IUM/SUM-l,R20 or
HP-2 ) battery x 8)
(Left + Right + Extra bass)
PMPO; 60 W (15 W + 15 W + 30 W)
(AC operation)
MPO; 27 W (7.5 W + 7.5 W + 12 W)
(AC operation)
RMS;l6W(4W+4W+8W)
(DC operation, 10% T.H.D.)
8 cm (3-l /8”) free-edge super woofer
xl
12 cm (4-3/4”) free-edge woofer x 2
Tweeter x 2
Mixing mic; 600 ohms
CD/Line in; 50 k ohms
Headphones; 16-50 ohms
(recommended 32 ohms)
Width; 560 mm 122-l/16”)
Height; 210 mm (8-5/16”)
Depth; 187 mm (7-3/8”)
5 kg 11 1 Ibs.) without batteries
Radio
Frequency range: FM; 87.6
- 108 MHz
AM; 526.5 - I,6065 kHz
Tape recorder
Tape: Compact cassette tape
Frequency response: 60 - 12,000 Hz (Normal tape)
Signal/noise ratio: 55 dB (TAPE 1, playback)
50 dB (TAPE 2, recording/playback)
Wow and flutter:
0.15 oh (WRMS)
4
Specifications for this model are subject to change without
prior notice.
STRINGING OF DIAL CORD
‘0” Pdnt
Figure 2-1
Dial Cord Asiy(g4g)
.
‘I
5 Turns
drum
1236)
Figure 2-2
-2.-

NAMES OF PARTS
1. Volume Control
2. Graphic Equalizer Controls
3. Headphones Socket
4. Surround Speaker Sockets
5. Beat Cancel Switch
6. Dubbing Speed Switch
7. Power/Function Switch
8. CD/Line Input Sockets
9. Mixing Microphone Socket
10. Radio Band Selector
11. Tuning Control
12. Power Indicator
13. Surround indicator
14. Extra Bass Indicator: X-BASS 3
15. Extra Bass Switch: X-BASS
16. Surround Switch
17. FM Stereo Indicator
18. Bass Boost Horn
19. Cassette Compartment
20. Tape Mode Switch
21. TAPE 2) Pause Button: II
22. TAPE 1, 2) Stop/Eject Button: N
23. TAPE 2) Fast Forward Button: M
24. TAPE 2) Rewind Button: ),
25. TAPE 1, 2) Play Button: 4
26. TAPE 2) Record Button: l
I
29
27. FM Telescopic Rod Aerial
28. AC Power Input Socket
-3-
29. Battery Compartment

DISASSEMBLY
Caution on Disassembly
Follow the below-mentioned notes when disassembling the
unit and reassembling it, to keep its safety and excellent
performance:
1. Take cassette tape out of the unit.
2. Be sure to remove the power supply plug from the
wall outlet before starting to disassemble the unit and
remove the batteries from the unit.
3. Take off nylon bands or wire holders where they need be
removed when disassembling the unit. After servicing
the unit, be sure to rearrange the leads where they were
before disassembling.
4. Take sufficient care on static electricity of integrated
circuits and other circuits when servicing.
Rear
Cabins
Plug-
PWB
STEP REMOVALPROCEDURE FIGURE
1. Battery lid..
. . . . . . . . . . . . (A,)
4-1
2. Screw..............(A2)x 8
1. Screw..............(Bl)x I
1 2 1 ;;;pnism i2’ ~~ecrharli.“::.mode....iB2)x, 1
3. Screw ....*.........(B3)x!j
4. Socket..............(B4)x 3 4-3
3
Main PWB 1. Screw
..............
(Cj)x6
4-2.3
(with Frame) 2. Tip ................((-2)
x,
4-3
4Socket PWB 1. Screw..............(Dl)x 3 4-4
5Power
PWB
1. Screw ..............(El)x 3 4-4
(Ahx8
d3x65mm
Figure 4-I
Figure 4-4
(Av3)x 2
Figure 4-2
-hJvl;fanism
-?a
(B3lx5
d3xlOmm
Xl
:IOmm
I
(C 11x4
Main PWB
83xI2mm
Figure 4-3
Socket PWB
Q
* (El) x2
Power PWB
,(C2) xl
(DlJx3
03 xl Omm
04 x12mm
-4-

REMOVING AND REINSTALLING THE MAIN PARTS
TAPE MECHANISM SECTION
Perform steps 1 and 2 of the disassembly method to remove the
tape mechanism.
0 How to remove the playback, erase and record/playback
heads (See Fig. 5-l .)
1. Remove the two screws (Al) to remove the playback head.
2. Remove the two screws (A2) and shield cover (A3) to remove
the record/playback head.
3. Remove the two screws iA4j to remove the erase head.
Note:
Be careful not to lose the head azimuth springs.
Figure 5-l Figure 5-3Figure 5-3
l How to remove the pinch roller (See Fig. 5-2.)
1. Move the pinch roller sprin$‘(Bl) in the direction of arrow
@ to remove it from the play lever.
2. Move the pinch roller spring (Bl) in the direction of arrow
@to remove it from the pinch roller unit.
3. Remove the pinch roller in the direction of arrow 0.
(El)x3
P2x6mm
Q
, $@;;;a Metal
Pinch Rol ler
l How to remove the drive belt (See Figs. 5-3 and 5-4.)
1. Remove the four screws (Cl i to remove the flywheel bracket
and switch bracket.
2. Remove the drive belt iC2).
l How to remove the flywheel (See Fig. 5-4.)
1. Remove the capstan metal (Dl) and pull out the flywheel.
Note:
Be careful not to lose the three washers.
0 How to remove the motor. (See Fig. 5-4.)
~
1. Remove the three screws (El) to remove the motor.
cc 11x1
82.6x IOmm
Figure 5-4
,wheel(D2)
Figure 5-2
-5-

ADJUSTMENT
As for adjusting method refer to the relevant explanation in
Service Manual “ADJUSTMENT PROCEDURES OF AUDIO
PRODUCTS”.
MECHANISM SECTION
- Driving Force check
Torque Meter
Play: TW-2412
9 Torque Check
Specified Value
Over 140 g
Torque Meter Specified Value
Tape 1 Tape 2
Play: TW-2111 35 to 60
u.cm
30 to 65 a.cm
Fast forward: TW-2231 ) -
80 to 135 g.cm
Rewind: TW-2231
-
80 to 135 g.cm
* Head Azimuth
Test Tape
MTT-114
Instrument Connection
Speaker terminal
(Load resistance: 4 ohms)
* Tape Speed
Test Tape Adjusting Point Specified Value Instrument
C
onnection
Speaker
Normal terminal
speed MTT-111 Tape 2: VR501 3,000
+ 300 Hz (Load
resistance:
4 ohms)
TAPE2 AZIMUTH AfJJUSTWNT SCREIW
TAPE1 AZIMUTH
ADJUSTMENT SCREW
/
TAPE SECTION
Position of each switch or control
Volume Max
Beat cancel switch A/STEREO
Graphic equalizer Center
1 Tape speed
1 Normal
-1
Mechanism mode
Function
2
Tape
* Bias Oscillation Frequency/Bias Current check
Specified Value
A: 97 + 4 kHz
Beat cancel B: -2 t 2 kHz for A
C: -7
f 2kHz for
B
Resistor for measurement: 100 ohms 38
3~ 5 mV
. Erase Current check
Specified Value
Resistor for measurement: 1 ohm 65 4 20
mV
. Playback Amplifier Sensitivity check
Test Tape Specified Vaiue Instrument Connection
MTT-118 1.0 V t 3 dB Speaker terminal
(Load resistance: 4 ohms)
ISOCKET PWB-~31 MAIN PWB-Al
/
/
:
r
r---L
TAPE2
NORMAL
SP(R) CvP74Z
Figure 6 ADJUSTMENT POINTS
-6-

TUNER SECTION
fL: Low-range frequency
fH: High-range frequency
. FM IF/RF
Test Stage
Specified Value/
Adjusting Point Instrument Connection
IF
Tl
. VCO Frequency
Adjusting Point Specified Value
VRl 38 kHz + 100 Hz Instrument Connection
Pin 6 of IC3
* AM IF/RF
Test Stage
IF
AM Band
Coverage
AM Tracking
Specified Value/
Adjusting Point Instrument Connection
T3
fL: L5Input: Antenna
(TPI)
fH: TC4Output: Pin 9 of IC2
600 kHz: L3
1,400 kHz: TC3
FM
BAND
COVERAGE
SW1
Ll c
E4
1 MAIN PwB-Ai)
-I-
J
Figure 7 ADJUSTMENT POINTS
-7-

TOP VIEW
I i 510
1 I 2
I
3
I 4 5
Figure 8 TAPE MECHANISM EXPLODED VIEW (l/Z)
I 6
I
-a-

A
B
C
D
,E
F
G
H
-
-
BOTTOM VIEW
512
8-\
I6
1
I 2
I
3
I
4
I
5
I
6
Figure 9 TAPE MECHANISM EXPLODED VIEW (2/2)
-9

6Oix4
‘SPl,Z
C
D
E
F
G
H
/
250
L
1
I
2
I
3
I 4
I
5
I
6
Figure 10 CABINET EXPLODED VIEW I
-lO-