Sony Walkman SRF-H3 User manual

SRF-H3
Australian Model SERVICE MANUAL
FM STEREO/AM HEADPHONE RADIO
SPECIFICATIONS
Frequency range:
FM: 87.6 – 108 MHz
AM: 530 – 1 710 kHz
Power output:
5.0 mW + 5.0 mW (at 10 % harmonic
distortion)
Headphone type:
Dynamic
Power requirements:
1.5 V DC, one size AAA (R03) battery
Mass:
Approx. 132 g (4.7 oz) incl. a battery
Design and specifications are subject to change
without notice.
Ver 1.0 2000. 07

— 2 —
SECTION 1
GENERAL
Getting Started
Installing the Battery
(See Fig. B)
1While pressing the battery
compartment lid, slide it to open.
2Insert one size AAA (R03) battery (not
supplied) with correct polarity.
3To close the lid, press and slide the lid
down until it clicks.
When to replace the battery
Replace the battery when the sound becomes
weak or distorted. Remove the old battery and
insert a new one.
Battery life (approximate hours)
Sony Sony
alkaline size AAA
sizeAAA (R03)
(LR03)
FM reception 80 40
AM reception 100 50
Notes on the battery
• Align the battery correctly.
• The dry battery cannot be charged.
• To avoid damage from possible battery
leakage, remove the battery when unit will
not be used for a long time.
Wearing the Radio
1Pull out the support band fully from
the headband.
2Adjust the headband and the support
band to fit your head.
Note on the support band
(See Fig. A)
When the radio not in use, put the support band
back by pushing down both ends as illustrated
and push it back underneath the headband.
Note on the light reflector
(See Fig. A)
This reflector reflects a car light at night for your
safety.
Playing the Radio
1 Set POWER to ON.
2Set BAND to select FM or AM.
For FM, set SENS to LOCAL if interference is
prevalent and reception is too strong. Under
normal condition, set it to DX.
3Turn TUNE (tuning) to tune in a station.
4Adjust the volume using VOL.
To turn off the radio
Set POWER to OFF.
AAA (R03) x 1
Head band
Light reflector
FM flexible
antenna
BAND
SENS
VOL
Driver
units POWER
Support band
Insert the #side of the
battery first.
Battery
compartment
Dial scale
A
TUNE
B
This section is extracted from
instruction manual.
1. Check theareaof your repairforunsoldered or poorly-soldered
connections. Checktheentire board surfacefor solder splashes
and bridges.
2. Check the interboard wiring to ensure that no wires are
"pinched" or contact high-wattage resistors.
3. Look for unauthorized replacement parts, particularly
transistors, that were installed during a previous repair. Point
them out to the customer and recommend their replacement.
4. Look forpartswhich, through functioning, showobvious signs
of deterioration. Point them out to the customer and
recommend their replacement.
5. Check the B+ voltage to see it is at the values specified.
6. 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.
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety checks before releasing the set to the customer.

— 3 —
SECTION 2
DISASSEMBLY
2Cabinet front (R) assy
Cabinet rear (R) assy
Claws
Claws
1
Precision screwdriver
3Holder
2Push this
portion down.
Cabinet rear (R) assy
1Unsolder two lead wires.
Model name (SRF-H3) Gear (tuning)
1Turn CV1 fully in the
direction of arrow.
Cabinet rear (R) assy
CV1
2
2-1. CABINET FRONT (R) ASSY
2-2. HOLDER (WITH DRIVER)
2-3. GEAR (TUNING) INSTALLATION
Note : Follow the disassembly procedure in the numerical order given.

— 4 —
SECTION 3
ELECTRICAL ADJUSTMENTS
FMVCO Adjustment
Procedure:
1. Connect thefrequencycounter to2and 1pins of IC2as shown
the figure right.
2. Tune the set to 98 MHz.
3. Adjust RV1 for 76 kHz Hz reading on frequency counter.
Specification Value:
FM RF signal
generator
Carrier frequency: 98 MHz
Modulation: no modulation
Output level: 0.1 V (100 dB)
0.01 µF
FM lead wire antenna terminal
Connection:
Adjustment Location:
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
T1 455 kHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter
L5 520 kHz
CT1-4 1,650 kHz
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L2 620 kHz
CT1-1 1,400 kHz
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
FM IF ADJUSTMENT
Adjust for a maximum reading on level meter
T2 10.7 MHz
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter
L4 87.35 MHz
CT1-3 108.05 MHz
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L3 87.35 MHz
CT1-2 108.05 MHz
[FM]
Setting:
BAND switch : FM
[AM]
Setting:
BAND switch : AM signal
AM RF signal
generator
30% amplitude modulation by
400 Hz signal.
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
FM RF signal
generator
75 kHz frequency deviation
by 1 kHz signal.
Output level: as low as possible
0.01 µF
FM lead wire antenna terminal
level meter
set
SP1, SP2 (speakers)
32 Ω+
–
Frequency counter
75,500 –76,500 Hz
IC2 Pin 2
+
–
frequency counter 33 k ΩAUDIO Board
IC2 Pin 1
[AUDIO BOARD] (Component Side)
RV1: MPX VCO
IC2
L2: AM TRACKING
L3: FM TRACKING
T1: AM IF
CT1-4:
AM FREQUENCY
COVERAGE
CT1-1:
AM TRACKING
CT1-2:
FM TRACKING
CT1-3:
FM FREQUENCY
COVERAGE
T2: FM IF
L5: AM FREQUENCY
COVERAGE
L4: FM FREQUENCY
COVERAGE
[TUNER BOARD] (Component Side)

SRF-H3
— 5 — — 6 —
• IC BLOCK DIAGRAMS
IC1 TA7792F
IC3 LA4537M
Note on Schematic Diagram:
• All capacitors are in µF unless otherwise noted. pF:µµF 50 WV or
less are not indicated except for electrolytics and tantalums.
• All resistors are in Ωand 1/4W or less unless otherwise specified.
•f: internal component.
•A: B+ Line.
•H: adjustment for repair.
• Power voltage is dc 1.5V and fed with regulated dc power supply
from battery terminal.
• Voltages are dc with respect to ground under no-signal conditions.
• Voltages are taken with aVOM (Input impedance 10 MΩ).
Voltage variations may be noted due to normal production toler-
ances.
• Signal path.
F:FM
f:AM
Note on PrintedWiring Board:
•X: parts extracted from the component side.
•b: Pattern from the side which enables seeing.
16
BPF FM RF IN
FM RF
IN
AM IF
IN
FM RF OUT
1
FM OSC
3
AM OSC
4
L2
FERRITE-ROD
ANTTENA
L5
BUFFER
Q1
CT1-1
CV1-1
CV1
TUNE
13 5
14
AM RF IN
AM MIX
OUT
FM MIX
OUT
FM MIX
AM MIX
AM OSC
FM OSC
CF1
12
T1
CF2
7
8 5
13
16
15 2
AM AGC
FM DET
VCO
R-CH
R-CH
RV2
38k 19k<90º19k<0º
AM DET AF
OUT
VCC1
R OUT
L OUT
9
RV1
VCO
L3
CT1-2
B+(R16)
B+(R16)
B+(R16)
B+(R16)
CV1-2
FM/AM
FRONT END
IC1(1/3)
STEREO MPX
IC2
SP1
SPEAKER
SP2
SPEAKER
FM:
AM:
ANT1
FM ANT
DX/LOCAL
L4
CT1-3
CV1-3
T2
B+
CT1-4
CV1-4
STEREO
DECODE
11
VOL
6
MPX
MPX
SENS
DX LOCAL
S1
S1-1
S1-2
9
POWER AMP
IC3
BAND
FM AM
S2
B+
2
AM B+
AM B+
POWER
OFF ON
S3
B+
16
•Signal path
FM FREQ. COVERAGE
AM FREQ. COVERAGE
FM TRACKING
AM TRACKING
AM IF
FM
IF
3
MUTE SWITCH
OUT 1
POWER GND
OUT 2
V
CC
POWER SWITCH
IN 1
PRE GND
IN 2
REF
POWER
SWITCH
MUTE
CIRCUIT
Amp1
Amp2
BIAS 6
7
8
9
101
2
4
5
POWER
SWITCH MUTE
BIAS
AMP
AMP
1
2
3
4
5 6
7
8
9
10 MUTE
R-OUT
GND
L-OUT
VCC
PWR
R-IN
GND
L-IN
REG
SECTION 4
DIAGRAMS
4-1. BLOCK DIAGRAM

SRF-H3
— 7 — — 8 —
4-2. SCHEMATIC DIAGRAM
16

SRF-H3
— 9 — — 10 —
4-3. PRINTEDWIRING BOARD
Ref. No. Location
D1 F-3
IC1 E-9
IC2 E-3
IC3 C-2
Q1 D-10
• Semiconductor
Location

*A-3670-048-A AUDIO BOARD, COMPLETE
**********************
3-902-546-01 TERMINAL (PLUS), BATTERY
< CAPACITOR >
C19 1-104-396-11 ELECT 10uF 20.00% 16V
C20 1-162-637-11 CERAMIC CHIP 0.47uF 16V
C21 1-163-081-00 CERAMIC CHIP 0.22uF 25V
C22 1-162-637-11 CERAMIC CHIP 0.47uF 16V
C23 1-163-275-11 CERAMIC CHIP 0.001uF 5.00% 50V
C24 1-163-022-00 CERAMIC CHIP 0.012uF 10% 50V
C25 1-163-022-00 CERAMIC CHIP 0.012uF 10% 50V
C26 1-162-638-11 CERAMIC CHIP 1uF 16V
C27 1-162-638-11 CERAMIC CHIP 1uF 16V
C28 1-163-117-00 CERAMIC CHIP 100PF 5% 50V
C29 1-163-117-00 CERAMIC CHIP 100PF 5% 50V
C30 1-124-229-00 ELECT 33uF 20% 10V
C31 1-163-077-00 CERAMIC CHIP 0.1uF 10% 25V
C32 1-124-635-00 ELECT 220uF 20.00% 6.3V
C33 1-163-077-00 CERAMIC CHIP 0.1uF 10% 25V
C34 1-163-077-00 CERAMIC CHIP 0.1uF 10% 25V
C35 1-124-635-00 ELECT 220uF 20.00% 6.3V
C36 1-124-635-00 ELECT 220uF 20.00% 6.3V
C37 1-163-031-11 CERAMIC CHIP 0.01uF 50V
< DIODE >
D1 8-719-981-95 DIODE MTZJ-2.7B
< IC >
IC2 8-759-945-89 IC BA1362FST1
IC3 8-759-822-48 IC LA4537M
< RESISTOR >
R22 1-216-049-11 RES-CHIP 1K 5% 1/10W
R23 1-216-069-00 METAL CHIP 6.8K 5% 1/10W
R24 1-216-296-91 SHORT 0
R25 1-216-296-91 SHORT 0
R26 1-216-084-00 METAL CHIP 30K 5% 1/10W
R27 1-216-084-00 METAL CHIP 30K 5% 1/10W
< VARIABLE RESISTOR >
RV1 1-228-994-00 RES, ADJ, METAL10K
RV2 1-241-130-00 RES, VAR, CARBON 20K/20K (VOL)
< SWITCH >
S3 1-553-510-11 SWITCH, SLIDE (POWER)
************************************************************
*A-3683-222-A TUNER BOARD, COMPLETE
**********************
3-831-441-99 CUSHION
3-902-555-01 SHEET (FERRITE-ROD ANTENNA)
< FILTER >
BPF1 1-236-839-11 FILTER, BAND PASS
< CAPACITOR >
C1 1-163-021-91 CERAMIC CHIP 0.01uF 10.00% 50V
C2 1-126-514-11 ELECT 22uF 20.00% 6.3V
C3 1-126-117-11 ELECT 330uF 20.00% 2V
C4 1-126-117-11 ELECT 330uF 20.00% 2V
C5 1-163-077-00 CERAMIC CHIP 0.1uF 10% 25V
C6 1-163-129-00 CERAMIC CHIP 330PF 5% 50V
C7 1-162-638-11 CERAMIC CHIP 1uF 16V
C8 1-163-222-11 CERAMIC CHIP 5PF 0.25PF 50V
C9 1-162-638-11 CERAMIC CHIP 1uF 16V
C10 1-163-100-00 CERAMIC CHIP 20PF 5% 50V
C11 1-163-077-00 CERAMIC CHIP 0.1uF 10% 25V
C12 1-163-021-91 CERAMIC CHIP 0.01uF 10.00% 50V
C13 1-163-101-11 CERAMIC CHIP 22PF 5.00% 50V
C14 1-163-093-00 CERAMIC CHIP 10PF 5% 50V
C15 1-126-154-11 ELECT 47uF 20% 6.3V
C16 1-163-033-91 CERAMIC CHIP 0.022uF 50V
C17 1-163-129-00 CERAMIC CHIP 330PF 5% 50V
C18 1-163-014-00 CERAMIC CHIP 0.0027uF 10.00% 50V
< FILTER >
CF1 1-567-097-61 FILTER, CERAMIC
CF2 1-578-677-11 FILTER, CRYSTAL
< VARIABLE CAPACITOR >
CV1 1-151-620-11 CAP, VARIABLE (TUNE)
< TRIMMER >
CT1 1-151-620-11 CAP, VARIABLE
< IC >
IC1 8-759-230-65 IC TA7792F
< COIL >
L1 1-414-142-61 INDUCTOR 1uH
L2 1-402-505-11 ANTENNA, FERRITE-ROD (MW)
L3 1-428-123-11 COIL, AIR-CORE
L4 1-428-122-11 COIL, AIR-CORE
L5 1-406-390-21 COIL (OSC)
AUDIO TUNER
Ref. No. Part No. Description Remarks Ref. No. Part No. Description Remarks
SECTION 6
ELECTRICAL PARTS LIST
NOTE:
• Due to standardization, replacements in the
parts list may be different from the parts
specifiedin the diagrams or the components
used on the set.
• -XX, -X mean standardized parts, so they
may have some difference from the original
one.
• Items marked “*” are not stocked since they
are seldom required for routine service.
Some delay should be anticipated when
ordering these items.
• CAPACITORS:
uF: µF
• RESISTORS
All resistors are in ohms.
METAL: metal-film resistor
METAL OXIDE: Metal Oxide-film resistor
F: nonflammable
• COILS
uH: µH
• SEMICONDUCTORS
In each case, u: µ, for example:
uA...: µA... , uPA... , µPA... ,
uPB... , µPB... , uPC... , µPC... ,
uPD..., µPD...
When indicating parts by reference number,
please include the board name.
Ref. No. Part No. Description Remarks Ref. No. Part No. Description Remarks
*1 A-3683-222-A TUNER BOARD, COMPLETE
2 X-3379-444-1 CABINET FRONT (R) ASSY
3 3-902-544-01 GEAR(TUNING)
4 3-902-551-01 SCALE(FM/AM), DIAL
5 3-309-597-31 SCREW(1.4), TAPPING,PRECISION
6 3-902-555-01 SHEET(FERRITE-ROD ANTENNA)
*8 3-902-552-01 PLATE, CLICK
9 3-902-546-01 TERMINAL (PLUS), BATTERY
10 X-3379-445-1 CABINET FRONT (L) ASSY
11 3-902-542-01 KNOB
12 3-902-547-01 SPRING, BATTERY COIL
13 3-318-203-51 SCREW (B1.7X12), TAPPING
14 3-363-940-01 PAD, EAR
15 3-902-539-01 LID, BATTERY CASE
*16 A-3670-048-A AUDIO BOARD, COMPLETE
17 3-902-549-01 CAP, ANTENNA
18 1-575-829-11 CORD, CONNECTION
19 3-902-542-11 KNOB
20 3-902-556-11 BELT, MAIN
21 3-902-537-11 BELT (SUB)
22 3-902-541-01 KNOB (VOLUME)
23 3-902-560-01 CABINET (REAR) (L)
24 3-902-538-01 HOLDER
25 3-902-538-01 HOLDER
26 3-902-543-01 KNOB (SENS)
27 3-902-540-01 KNOB (TUNING)
28 3-902-558-21 CABINET (REAR) (R)
L2 1-402-505-11 ANTENNA, FERRITE-ROD (MW)
SP1 1-505-114-11 DRIVER (HEADPHONE)
SP2 1-505-114-11 DRIVER (HEADPHONE)
ANT1 X-3379-374-1 ANTENNA ASSY
SECTION 5
EXPLODED VIEWS
NOTE:
• -XX, -X mean standardized parts, so they may
have some differences from the original one.
• Items marked “*” are not stocked since they
are seldom required for routine service. Some
delayshould be anticipated whenorderingthese
items.
• Themechanical parts withno reference number
in the exploded views are not supplied.
• Hardware (# mark) list and accessories and
packing materials are given in the last of this
parts list.
— 11 — — 12 —
18
17
6
L2
13
8
1SP2
14
SP1
3
4
2
5
15 16
10
11
9
12
8
ANT 1
20
21
19
27
26
28
25
24
22
23

— 13 —
< TRANSISTOR >
Q1 8-729-109-44 TRANSISTOR 2SK94
< RESISTOR >
R1 1-216-295-00 SHORT 0
R3 1-216-045-00 METAL CHIP 680 5% 1/10W
R4 1-216-295-00 SHORT 0
R5 1-216-021-00 METAL CHIP 68 5% 1/10W
R8 1-216-035-00 METAL CHIP 270 5% 1/10W
R9 1-216-017-91 RES-CHIP 47 5% 1/10W
R10 1-216-043-91 RES-CHIP 560 5% 1/10W
R11 1-216-296-91 SHORT 0
R12 1-216-295-00 SHORT 0
R13 1-216-009-00 RES-CHIP 22 5% 1/10W
R14 1-216-073-00 METAL CHIP 10K 5% 1/10W
R15 1-216-295-00 SHORT 0
R16 1-216-009-00 RES-CHIP 22 5% 1/10W
R17 1-216-061-00 METAL CHIP 3.3K 5% 1/10W
R18 1-216-049-11 RES-CHIP 1K 5% 1/10W
R19 1-216-025-11 RES-CHIP 100 5% 1/10W
R21 1-216-049-11 RES-CHIP 1K 5% 1/10W
< SWITCH >
S1 1-554-667-00 SWITCH, SLIDE (SENS)
S2 1-553-510-11 SWITCH, SLIDE (BAND)
< TRANSFORMER >
T1 1-404-920-21 TRANSFORMER, IF
T2 1-404-921-21 TRANSFORMER, DISCRIMINATOR
************************************************************
MISCELLANEOUS
**************
SP1 1-505-114-11 DRIVER (HEADPHONE)
SP2 1-505-114-11 DRIVER (HEADPHONE)
ANT1 X-3379-374-1 ANTENNA ASSY
************************************************************
ACCESSORIES & PACKING MATERIALS
********************************
3-049-014-11 MANUAL, INSTRUCTION (ENGLISH)
TUNER
Ref. No. Part No. Description Remarks

SRF-H3
— 14 —
Sony Corporation
Audio Entertainment Group 2000G16024-1
Printed in Japan ©2000.7
Published by PE General Engineering Dept.
9-927-940-31