Sony Sports Walkman WM-FS473 User manual

Ver 1.0 1998. 05
MICROFILM
WM-FS473
SERVICE MANUAL
SPECIFICATIONS
US Model
Canadian Model
AEP Model
E Model
Model Name Using Similar Mechanism NEW
Tape Transport Mechanism Type MF-WMFS473
Frequency range FM : 87.5 – 108 MHz
AM : 530 – 1710kHz
(US, Canadian model)
531 – 1602kHz (AEP, E model)
Power requirements 3V DC batteries (AA) R6 x2
Dimensions 104.2 x 127.3 x 51.8 mm (4 1/8 x 51/8x 21/8 inches)
(w/h/d) incl. projecting parts and controls
Mass Approx. 260g (9.2 oz)
Approx.340g (12 oz) incl. batteries and a cassette
Supplied accessory Stereo headphones or Stereo earphones (1)
Design and specifications are subject to change without notice.
RADIO CASSETTE PLAYER

– 2 –
Flexible Circuit Board Repairing
• Keep the temperature of the soldering iron around 270°C
during repairing.
• Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
• Be careful not to apply force on the conductor when soldering
or unsoldering.
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be
damaged by heat.
TABLE OF CONTENTS
Specifications ........................................................................... 1
1. GENERAL
Location of parts and controls............................................ 2
2. SERVICE NOTE........................................................... 3
3. DISASSEMBLY
3-1. Cover Removal ........................................................... 4
3-2. Display Board Removal ............................................. 4
3-3. Cassette Lid Assy Removal ........................................ 5
3-4. Chassis section, Headphone Jack Board Removal ..... 5
3-5. Mechanism Deck, Main Board, Belt Removal........... 6
4. ADJUSTMENTS
4-1. Mechanical Adjustments ............................................ 7
4-2. Electrical Adjustments ................................................ 7
5. DIAGRAMS
5-1. Explanation of IC Terminals..................................... 10
5-2. Block Diagram...........................................................11
5-3. Printed Wiring Boards (Main Section) ..................... 13
5-4. Schematic Diagram (Main Section) ......................... 15
5-5. Schematic Diagram (Display Section) ..................... 18
5-6. Printed Wiring Boards (Display Section) ................. 21
6. EXPLODEDVIEWS
6-1. Cassette Lid Section ................................................. 23
6-2. Main Board Section .................................................. 24
6-3. Mechanism Deck Section (MF-WMFS473) ............ 25
7. ELECTRICAL PARTS LIST................................... 26
SECTION 1
GENERAL This section is extracted from
instruction manual.

– 3 –
SECTION 2
SERVICE NOTE
WATERPROOFED SECTION
Set the Apositions to corner.
then push down to grove.
Note : In case the parts in the figure are removed for repair, treat them to protect from water drop following the instructions in the figure
(spread grease, bond etc.)
• Sony grease SGL-601 : 7-651-000-10
Note : Clean the attachement portion
and shaded area with cloth.
Paking (cabinet)
A
A
Cassette lid assy
Screw
Joint (VOL. B)
O ring
(Apply sony grease SGL-601)
Knob (VOL)
Cabinet (rear) assy

– 4 –
SECTION 3
DISASSEMBLY
Note:Followthedisassemblyprocedureinthenumericalordergiven.
3-1. COVER REMOVAL
3-2. DISPLAY BOARD REMOVAL
r
Theequipmentcanberemo vedusingthef ollo wingpr ocedure .
Cassette lid assy
3
2
Screws
1 Flexible board
Display board
Cassette lid assy
Arm ass
y
Backle
Cover
5 Screws
4
2
1
3
Claws
Chassis section, Headphone jack board
Cover
Set Diaplay board
Cassette lid assy Mechanism deck, Main board, Belt

– 5 –
3-3. CASSETTE LID ASSY REMOVAL
3-4. CHASSIS SECTION, HEADPHONE JACK BOARD REMOVAL
1 Screws (+P 2x12)
43
3
1
2
Headphone jack board
Chassis section
Cabinet (rear) assy
Cabinet (rear) assy
Knob (VOL)
RV301
Main board
2 Claws
Cassette lid assy
2 Screw
2 Screw
3
1
Flexible board
Note:Wheninstallthec hassissection
1. TurnR V301full ytoarr owdirection.
2. Turnknob(V OL)fullytoarr owdirection.
3. FitRV301toholeofknob(V OL)andthen
installthechassissection.

– 6 –
3-5. MECHANISM DECK, MAIN BOARD, BELT REMOVAL
Main board
2 Screws (2x5)
7
6
4
9
8
Chassis
3 Claw
3 Claw
5 Screw
3 Claw
Belt Mechanism dec
k
Red
Red
1 Remove
solder
Black
Orange
Gray
Black
White

– 7 –
SECTION 4
ADJUSTMENTS
4-2. ELECTRICAL ADJUSTMENTS
PRECAUTION
• Suppliedv olta ge: 2.5V.
• Switchandcontrolposition
SETswitch:NORM
VOLUMEcontrol:maximum
MENUswitch:NORM
TestTape
Type Signal Used for
WS-48A 3kHz, 0dB Tape Speed Adjustment
Tape SpeedAdjustment
Procedure :
1. Pla ybac kWS-48A(tapecenterpar t)intheREVstateandadjust
RV601so thatthefrequenc ycounterreadingbecomes2,990Hz
–3,010Hz.
2. Pla ybac kWS-48A(tapecenter)intheFWDstate .
Checkthatfrequencycounterreadingiswithin1.5%oftheread-
ingofstep1.
Adjustment Location :
set
test tape
WS-48A
(3kHz, 0dB) frequency counte
r
J101 (phones)
16 Ω
4-1. MECHANICAL ADJUSTMENTS
PRECAUTION
1. Cleanthefollowingpartswithadenatured-alcohol-moistened
swab: playbackhead pinchroller
capstan rubberbelt
2. Dema gnetiz ethepla ybac kheadwithaheaddema gnetiz er.
3. Donotuseamagnetizedscrewdriverfortheadjustments.
4. Aftertheadjustments,applysuitablelockingcompoundtothe
partsadjusted.
5. Theadjustmentsshouldbeperformedwiththeratedpowersup-
plyvolta ge(2.5 V)unlessotherwisenoted.
Torque Measurement
Mode Torque Meter Meter Reading
FWD 20 - 42 g • cm
CQ-102C (0.28 -0.58 oz• inch)
FWD less than 2 g • cm
back tension (less than 0.03 oz• inch)
REV 20 - 42 g • cm
CQ-102RC (0.28 -0.58 oz• inch)
REV less than 2 g • cm
back tension (less than 0.03 oz• inch)
FF, REW CQ-201B more than 60 g • cm
(more than 0.83 oz• inch)
RV601

– 8 –
TUNER SECTION
AM Section
BAND : AM
FM Section
BAND: FM
* Repeattheproceduresineachadjustmentseveraltimes,andthe
frequencycoverageandtrackingadjustmentsshouldbefinally
donebythetrimmercapacitors.
Frequency CoverageAdjustment
Setting :
nomark : COM
< > :AEP,Emodelonl y
AM IF ALIGNMENT
Adjust for a maximum reading on level meter.
T1 450kHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust part Frequency display Reading on digital
voltmeter.
T2 530kHz 1.25 – 1.35V
< 531kHz>
Confirmation 1,710kHz less than 10V
AMTRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L1 620kHz < 621kHz>
CT1 1,400kHz< 1,395kHz>
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust part Frequency display Reading on digital
voltmeter.
L3 87.5MHz 3.7 – 3.9V
Confirmation 108MHz less than 10V
FMTRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L2 87.5MHz
Confirmation 108MHz
AM RF signal
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
Put the lead-wire
antenna close to
the set.
FM RF signal
generator
75kHz frequency deviation by
400Hz signal.
Output level : as low as possible
TP27 (ANT IN
)
(GND)
0.01
µ F
set
16
Ω
J101 (phones)
level mete
r
digital voltmeter
(DC range)
TP19 (VT)
(GND)
[MAIN BOARD] (Conductor side)

– 9 –
Adjustment Location :
L1 : AM Tracking Adjustment CT1 : AM Tracking Adjustment
L2 : FM Tracking Adjustment
T2 : AM Frequency Coverage Adjustment
L3 : FM Frequency Coverage Adjustmen
t
T1 : AM IF Alignment
[MAIN BOARD] (Conductor Side)
Connection Point :
[MAIN BOARD] (Component side)

– 10 –
Pin No. Pin name I/O Description
1 – 3 COM1 – COM3 O Common output terminal.
4 – 20 S1 – S17 O Segment output terminal.
21 – 26 KR0 – KR5 O Key return timing output terminal.
27 – 30 K0 – K3 I Key input.
31 – 36 T0 – T5 O Key return timing output.
37 NOM/METAL O Tape normal/metal selection output.
38 TAPE ON I Tape power (MD power) ON Det terminal.
39 LOCAL/DX O Local/DX selection output.
40 MEGA BASS O Mega bass ON/OFF control output.
41 MONO/ST O Mono/Stereo selection output.
42 BAND O FM/AM band selection output.
43 I Power initial terminal.
44 TAPE & RADIO O Tape & Radio +B ON/OFF control.
45 AVLS O AVLS control terminal.
46 BEEP O Beep signal output terminal.
47 MUTE ON O Mute signal output terminal. H : Mute ON
48 TEST I Test terminal (Connected to ground).
–––––––––––––
49 HOLD I Hold detection terminal.
50 IF IN I IF input terminal.
51 RADIO ON O Radio +B ON/OFF control.
52 DO O PLL error signal output.
53 GND – Ground.
54 FM IN I FM local oscillator input terminal.
55 AM IN I AM local oscillator input terminal.
56 VDD – Power supply terminal (+2.8V).
––––––––––––––
57 RESET I System reset terminal. L : Reset
58 X OUT O Crystal oscillator terminal (75kHz).
59 X IN I Crystal oscillator terminal (75kHz).
60 VXT – Terminal to which external capacitor for stabilization of crystal oscillator power supply is
connected.
61 VLCD – LCD drive power supply set-up terminal.
62 C1 – LCD drive power supply set-up terminal.
63 C2 – LCD drive power supply set-up terminal.
64 VEE – 1.5V constant voltage power supply terminal for LCD drive.
SECTION 5
DIAGRAMS
5-1. EXPLANATION OF ICTERMINALS
IC701 TC9322FB-603 (LCD DRIVE/SYSTEM CONTROL)