Sony ICF-903L Service Manual ▷ View online
1
A
B
C
D
E
F
G
H
I
J
2
3
4
5
6
7
8
9
10
11
12
13
14
3
D401
D402
C403
C404
C401
R401
R402
JC402
TP404
WHT/BLK
BLK
WHT/BLK
BLK
BLK
BLK
BLK
TP406 TP405
TP402
TP403
MAIN BOARD
CN1
POWER BOARD
T401
POWER
TRANSFOMER
C406
TP401
L401
S401
CN401
1-677-386-
(11)
11
1
6
1
4
5
6
6
ACJ1
~ AC IN
EPJ1
v
S401
OPERATION
ON
STANDBY
DRY BATTERY
SIZE " D "
(IEC DESIGNATION R20)
4PCS, 6V
C402
SP1
SPEAKER
BLK
BRN
R302
JC303
JC302
JC301
R301
R307
C303
C304
R306
R305
C302
R304
C301
R303
TP301
TP310(+B)
TP302
KEY BOARD
1-677-388-
D301
TUNE
D303
FM3
SW304
MANUAL
D304
FM2
D302
FM1
SW303
FM3
SW302
FM2
SW301
FM1
PRESET
1
2
MAIN BOARD
CN201
MAIN
BOARD
04
TP308
(LED2)
TP307
(LED3)
TP309
(LED1)
TP306
(MANU)
TP311
WHT/
BLK
BLK
(TUNE LED)
TP305
(PRE3)
TP304
(PRE2)
TP303
(PRE1)
(11)
11
– 11 –
– 12 –
ICF-903L
Note:
• X
: parts extracted from the component side.
• Y
: parts extracted from the conductor side.
•
f
: internal component.
• b
: Pattern from the side which enables seeing.
4-2. PRINTED WIRING BOARDS (1/2)
D301
C-3
D302
C-7
D303
C-4
D304
C-6
D401
D-12
D402
D-12
• Semiconductor
Location
Ref. No.
Location
(Page 13)
(Page 14)
(Page 13)
1
A
B
C
D
E
F
G
H
I
J
2
3
4
5
6
7
8
9
10
11
12
13
14
R20
JC5
D201
JC3
JC7
JC9
JC2
JC1
JC37
JC29
JC36
JC22
JC15
JC21
JC20
JC17
JC33
JC32
JC31
JC26
JC25
JC34
JC27
JC30
JC38
JC12
JC13
JC11
JC4
R201 C207
C204
C202
R209
C1
L1
C2
C2
C3
C5
D5
R25
C43
JC14
C4
JC18
JC19
C13
C12
C15
C34
C44
R18
R23
R17
C28
C36
C29
R4
D3
C16
R9
C205
D202
D2
R13
C18
C14
R208
D203
R216
C101
C38
R103
R104
R107
R101
D101
C6
R2
JC16
C42
L4
R3
JC24
R6
C32
R105
L102
C105
C107
C104
C19
C23
C37
R106
R102
R11
C106
R14
C24
C45
C33
R8
JC28
R214
R210
R211
C41
R1
R207
C206
R203
R202
JC8
R213
C203
JC6
C208
R215
R212
R204
R205
R206
Q201
Q202
Q1
D1
Q9
Q2
Q5
Q8
Q4
CF3
CF2
CF1
Q101
Q6
Q7
Q3
Q103
Q102
Q203
IC101
TP12(D/D)
CT6
ANT1
FM
TELESCOPIC
ANTENNA
1-677-385-
RED
CLEAR
BLK
GRN
BLU
L2
FERRITE-ROD
ANTENNA
1
2
1
2
KEY BOARD
CN301
KEY
BOARD
CN301
3
POWER
BOARD
CN401
TP31
TP30
TP14
TP21
TP13
TP26
TP28
TP32
TP23
TP18
TP17
TP24
TP27
TP29
B C E
B C E
B C E
B C E
B C E
B C E
B C E
E C B
E C B
E C B
E C B
E C B
E C B
E C B
E C B
TP4(+B)
WHT/BLK
BLK
WHT
/BLK
/BLK
BLK
BLK
BLK
TP5
(REG)
TP7
(GND)
TP6 (AUDIO)
TP
RF
RF
GND
TP33 (BAND)
T1
C7
C10
CT2
BLU
BLK
CLEAR
GRN
CT1
CT3
CT5
C8
C11
C9
FM PRESET
S1-4
S1-1
S1-3
S1-2
S1-6
S1-8
S1-7
S1-5
C201
TP25
(RESET)
TP1
(ANT)
TP20
TP16
TP15
8
14
7
1
7
1
9
1
8
14
11
20
10
1
1
3
5
4
X201
04
IC204
TP22
TP19
CT7
CT8
C30
R26
C31
C27
C26
C22
C21
C35
CF4
C20
CV1
TUNING
CV1-2
CV1-1
L2-2
LW
L2-1
MW
S1
(BAND)
SW LW MW FM
MAIN BOARD
TP32
(TULED)
TP3
(DETOUT)
CN201
CT4
IC201
IC205
IC202
L101
C102
RV202
(FM TUNING)
RV201
RV2
TONE
RV1
VOL
VOL
RV205
FM1
RV206
FM2
RV208
FM3
1
3
5
4
L5
L6
RED
L3
L10
L9
L8
TP9(VT)
TP8
(REG)
TP2
1
15
10
1
16
20
30
3
2
BPF1
IC2
(FM ANT)
(11)
11
ICF-903L
– 13 –
– 14 –
4-3. PRINTED WIRING BOARD (2/2)
Note:
• X
: parts extracted from the component side.
• Y
: parts extracted from the conductor side.
•
f
: internal component.
• b
: Pattern from the side which enables seeing.
D1
H-6
D2
E-8
D3
E-9
D5
I-8
D101
B-12
D201
I-2
D202
F-7
D203
B-11
IC2
D-10
IC101
B-12
IC201
H-3
IC202
I-5
IC204
E-6
IC205
I-3
• Semiconductor Location
Ref. No.
Location
Ref. No.
Location
Q1
H-6
Q2
D-11
Q3
C-8
Q4
C-8
Q5
B-8
Q6
B-8
Q7
C-8
Q8
C-8
Q9
I-8
Q101
B-6
Q102
B-6
Q103
B-12
Q201
H-3
Q202
H-2
Q203
H-4
(Page 11)
(Page 12)
(Page 11)
4-4. SCHEMATIC DIAGRAMS
– 15 –
– 16 –
ICF-903L
Note:
• All capacitors are in µF unless otherwise noted. pF: µµF
• All capacitors are in µF unless otherwise noted. pF: µµF
50 WV or less are not indicated except for electrolytics
and tantalums.
and tantalums.
• All resistors are in
Ω
and
1
/
4
W or less unless otherwise
specified.
•
f
: internal component.
•
C
: panel designation.
•
U
: B+ Line.
•
H
: adjustment for repair.
• Total current is measured with power on.
• Power voltage is dc 4.5 V and fed with regulated dc power
• Power voltage is dc 4.5 V and fed with regulated dc power
supply from battery terminal.
• Voltage is dc with respect to ground under no-signal
(detuned) condition.
no mark : FM
(
no mark : FM
(
) : MW/LW/SW
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal produc-
tion tolerances.
tion tolerances.
• Signal path.
F
: FM
f
: MW
Note: The components identified by mark
0
or dotted line
with mark
0
are critical for safety.
Replace only with part number specified.
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