Sony ICF-M88B - S2 Sports Bicycle Radio User manual

SERVICE MANUAL
FM/AM PLL SYNTHESIZED RADIO
US Model
Canadian Model
SPECIFICATIONS
ICF-M88B
Ver 1.0 2004.05
9-877-839-01
2004E05-1
© 2004.05
Sony Corporation
Personal Audio Company
Published by Sony Engineering Corporation
Battery Life (Approx. hours) (JEITA*)
When using FM AM
Sony alkaline size AA (LR6) 66 84
Sony size AA (R6) 23 31
*Measured by JEITA (Japan Electronics and Information Technology Industries
Association) standards.
The actual battery life may vary depending on circumstances of use.
Time display: 12-hour system
Frequency range:
Band Range Channel step
FM 87.5 - 108 MHz 0.1 MHz
AM 530 - 1 710 kHz 10 kHz
531 - 1 710 kHz 9 kHz
Speaker: Approx. 50 mm (2 inches) dia, 8
Power output: 80 mW (at 10% harmonic distortion)
Power requirements: 3V DC, two size AA (R6) batteries
Dimensions :
Approx. 166.8 ×70 ×95 mm (w/h/d) (6
5
⁄
8 ×2
7
⁄
8 ×3
3
⁄
4
inches) incl.
projecting parts and control.
Mass: Approx. 281.4 g (9.93 oz) incl. batteries / excl. accessories
Supplied accessories:
Mount with wheel sensor (1), Thick/Thin rubber pads (2 each),
Wheel magnet (1), Zip ties (5), Double-sided tape (1), Screws (2)
Design and specifications are subject to change without notice.

2
ICF-M88B
TABLE OF CONTENTS
1. SERVICING NOTES ............................................... 2
2. GENERAL ................................................................... 3
3. DISASSEMBLY
3-1. Disassembly Flow ........................................................... 4
3-2. Cabinet (Lower) Block .................................................... 4
3-3. Chassis Assy .................................................................... 5
3-4. MAIN Board.................................................................... 5
4. TEST MODE.............................................................. 7
5. ELECTRICAL ADJUSTMENTS ......................... 8
6. DIAGRAMS
6-1. Printed Wiring Boards – TUNER Section –................... 10
6-2. Schematic Diagram – TUNER Section – ....................... 11
6-3. Printed Wiring Board
– PANEL/POWER SUPPLY Section – ........................... 12
6-4. Schematic Diagram
– PANEL/POWER SUPPLY Section – ........................... 13
7. EXPLODED VIEWS
7-1. Cabinet (Upper) Section .................................................. 16
7-2. Chassis Section................................................................ 17
7-3. Cabinet (Lower) Section.................................................. 18
8. ELECTRICAL PARTS LIST................................ 19
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.
SECTION 1
SERVICING NOTES
UNLEADED SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with
the lead free mark due to their particular size)
: LEAD FREE MARK
Unleaded solder has the following characteristics.
•Unleaded solder melts at a temperature about 40 ˚C higher
than ordinary solder.
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to
about 350 ˚C.
Caution: The printed pattern (copper foil) may peel away if
the heated tip is applied for too long, so be careful!
•Strong viscosity
Unleaded solder is more viscou-s (sticky, less prone to flow)
than ordinary solder so use caution not to let solder bridges
occur such as on IC pins, etc.
•Usable with ordinary solder
It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.

3
ICF-M88B
SECTION 2
GENERAL This section is extracted from
instruction manual.
Location of Controls
R
A
D
I
O
P
O
W
E
R
L
I
G
H
T
E
N
T
E
R
/
S
E
L
E
C
T
T
U
N
E
M
O
D
E
B
A
N
D
/
S
E
T
V
O
L
B
A
N
D
/
S
E
T
T
U
N
E
M
O
D
E
RADIO POWER
LIGHT
VOL
E
N
T
E
R
/
S
E
L
E
C
T
MP H
AM
PM
FM
FREEZE
PRESET
MHz
MP H
kHz
km/h inc h
AM
km/h
mile
CLOCK ODO DIST RT AVG MAX
mm
RADIO P OWER LIGHT ENTER/S ELECT TUNE MODE BAND/SET
VOL*
FM antennaFM SENS
DX/LOCAL
Jog lever
*The re is a tactile dot beside VOL to show the direction to turn up
the volume.
Setting the Clock
The clock time display of this unit is a 12-hour system.
When the batteries are first installed, AM 12:00 flashes and CLOCK turns on
in the display.
1Press RADIO POWER to turn off the power.
2Press MODE/FREEZE repeatedly until CLOCK appears.
3Hold down ENTER/SELECT for more than 2 seconds until
AM 12 starts flashing.
4Push the Jog lever towards +or –to adjust the hour, then press
ENTER/SELECT.
The beep sounds and the minute setting starts to flash.
If you hold down the Jog lever towards +or —, the digit changes rapidly.
Midnight is indicated as AM 12:00 and Noon is indicated by PM 12:00.
g
5 Repeat step 4above to adjust the minutes.
: starts flashing and the clock starts operating.
To set the current time exactly to the second, adjust the minute setting and
then press ENTER/S ELECT to synchronize it with a time signal (such as
the telephone time signal).
Note
If you do not push the Jog lever towards +or —, or ENTER/S ELECT within
about 65 seconds, the clock setting mode will be canceled.

ICF-M88B
4
•This set can be disassembled in the order shown below.
3-1. DISASSEMBLY FLOW
SECTION 3
DISASSEMBLY
Note: Follow the disassembly procedure in the numerical order given.
3-2. CABINET (LOWER) BLOCK
1 Slide the hook (battery case lid)
in the direction of arrow,
and open the battery case lid.
battery case lid
2 screw (P1.7 × 10)
4
5 Remove two solders.
3 four screws
(P1.7
× 10)
6 cabinet (lower) block
3-2. CABINET (LOWER) BLOCK
(Page 4)
3-3. CHASSIS ASSY
(Page 5)
3-4. MAIN BOARD
(Page 5)
SET

ICF-M88B
5
3-4. MAIN BOARD
3-3. CHASSIS ASSY
1 Remove five solders.
4 screw
5 chassis assy
3 button assy
1 Remove two solders.
2 two hooks
3 screw
4 MAIN board
1 Remove the solder.
1 Remove two solders.
2 hook

ICF-M88B
6
POSITION OF LEAD WIRES
three ditches
two ditches
boss
boss
lead wire (battery terminal (+))
cabinet (lower) block
lead wire (red)
lead wire (gray)
lead wire (red)
lead wire (gray)
DX/LOCAL board
lead wire (black)

7
ICF-M88B
TP117
(KR3)
TP115
(KS1)
TP116
(KS0)
IC101
– KEY BOARD (Conductor Side) –
SECTION 4
TEST MODE
EEPROM INITIALIZE MODE
Procedure:
1. Turn on the power to place the set in the standby state.
2. Press the [BAND/SET], [LIGHT] and [MODE/FREEZE] keys
simultaneously for 5 seconds, or short the TP116 (KS0) and
TP117 (KR3) on the key board.
3. When the EEPROM initialize mode is activated, the BEEP
1is outputted and “dEL” is displayed on the LCD for one
second.
4. After one second elapsed, the BEEP 2is outputted, and the
EEPROM initialize mode is deactivated and the set returns to
the standby state.
LCD AND KEY TEST MODE
Procedure:
1. Turn on the power to place the set in the standby state.
2. Short the TP115 (KS1) and TP117 (KR3) on the key board.
3. When the LCD and key test mode is activated, the BEEP 1is
outputted and the LCD becomes all lit state.
4. Each time a key is pressed, the segment assigned to each key
turns off (see below). Also, if the [LIGHT] key is pressed, the
LCD back light turns on. (It turns off at the release of LCD
and ket test mode)
5. When all keys were pressed, the BEEP 2is outputted, and
the LCD and key test mode is deactivated and the set returns
to the standby state.
Note 1:The pulse input is ignored during each test mode.
Note 2:In the event that theVDET1 terminal (pin rl of IC101) on the key
boarddetects“L” duringeach testmode,the test mode isdeactivated
and the set returns to the standby state.
Note 3:The amplifierpower turns onby the mainclock operation to prepare
for the BEEP output during each test mode.
Key Segment Display
POWER S0, S2, S4 below LCD display-1
TUNE MODE S6, S8, S10 below LCD display-2
BAND/SET S12, S14, S16 below LCD display-3
+S18, S20, S22 below LCD display-4
–S3, S5, S7 below LCD display-5
RESET S9, S11, S13 below LCD display-6
MODE/FREEZE S15, S17, S19 below LCD display-7
ENTER/SELECT S21, S23, S25 below LCD display-8
LIGHT S1, S24 below LCD display-9
MPH
AM
PM
FM
FREEZE
PRESET
MHz
MPH
kHz
km/h inch
AM
km/h
mile
CLOCK ODO DIST RT AVG MAX
mm
LCD display
MPH
kHz
km/h inch
LCD display-1
mile
RT AVG MAX
LCD display-2
AM
PM
CLOCK ODO
LCD display-3
DIST
LCD display-4
MPH
FM
AM
km/h
mm
LCD display-5
FREEZE
LCD display-6
PRESET
MHz
LCD display-7
LCD display-8
LCD display-9
Connecting Location:

8
ICF-M88B
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
T1 450 kHz
AM VCO VOLTAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
L1 530 kHz 1.2 ±0.1 V
Confirmation 1,710 kHz 7.2 ±0.5 V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
ANT1 590 kHz
CT1 1,490 kHz
FM VCO VOLTAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
Confirmation 108.0 MHz 8.9 ±1.0 V
Confirmation 87.5 MHz 2.3 ±0.5 V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L2 87.5 MHz
CT2 108.0 MHz
Adjustment Location: MAIN board (See page 9)
0 dB=1 µV
[AM]
Setting:
Function: RADIO
BAND: AM
[FM]
Setting:
Function: RADIO
BAND: FM
•Repeat the procedures in each adjustment several times, and
the trackingadjustmentsshould be finallydone by thetrimmer
capacitors.
•Remove FM antenna in FM adjustment.
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.
+
–
level mete
r
set
8 Ω
MAIN board
TP15 (AF GND)
MAIN board
TP12 (SP OUT)
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level:
as low as possible
+
–
level mete
r
MAIN board
TP15 (AF GND)
MAIN board
TP12 (SP OUT)
set
8 Ω
0.01 µ F
MAIN board
TP10 (RF GND)
MAIN board
TP13 (FM IN)
digital voltmete
r
TP9 (VT)
TP8 (GND)
100 k
Ω
MAIN board
SECTION 5
ELECTRICAL ADJUSTMENTS

ICF-M88B
99
Adjustment Location:
T1
AM IF Adjustment
L1
AM VCO Voltage Adjustment
FM Tracking Adjustment
CT2
L2
AM Tracking Adjustment
CT1
ANT1
– MAIN BOARD (Component Side) –
– MAIN BOARD (Conductor Side) –
IC1
TP15
(AF GND)
TP10
(RF GND) TP13 (FM IN)
TP9
(VT)
TP12
(SP OUT)
TP8
(GND)
IC2

ICF-M88B
1010
SECTION 6
DIAGRAMS
•Note for PrintedWiring Boards and Schematic Diagrams
Note on PrintedWiring Boards:
•X: parts extracted from the component side.
•Y: parts extracted from the conductor side.
•W: indicates side identified with part number.
•z: Through hole.
•f: internal component.
•: Pattern from the side which enables seeing.
•: Carbon pattern.
(The other layers' patterns are not indicated.)
Caution:
Pattern face side: Parts onthe patternface sideseen from
(Conductor Side) the pattern face are indicated.
Parts face side: Parts on the parts face side seen from
(Component Side) the parts face are indicated.
Note on Schematic Diagram:
•All capacitors are in µF unless otherwise noted. (p: pF)
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.
•C: panel designation.
•A: B+ Line.
•H: adjustment for repair.
•Power voltage is dc 3V and fed with regulated dc power
supply from battery terminal.
•Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
no mark : FM/AM
•Voltagesare taken withaVOM (Inputimpedance 10 MΩ).
Voltage variations may be noted due to normal produc-
tion tolerances.
•Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
•Circled numbers refer to waveforms.
•Signal path.
F: FM
f: AM
6-1. PRINTED WIRING BOARDS –TUNER Section – :Uses unleaded solder.
R21
R17
C36R19
C40C38
R3
C9
R24
JC4
JC9
R5
C12
C28
R11
R20
C44C45
C2
R2
C3
C6
C14
R13
C4
R7
JC12 JC11 JC10
C35
C8
R25
C11
JC3
C32
C30
C26
R9
R10
R4
C10
C39 C37
C42 C43
R1
C47 C46
L4
D1
IC2
IC1
D2
KA
D3
KA
Q3
BCE
C16
C20
C23
C24
JC5
R6
R14
C15
C29
C19
C13
R8
R12
JC8
R23
JC6
ECB
ECB
Q2
Q1
D4
X1
1
1
3
8
JW1 JW2 JW3
C22
C34
+
+
C31
+
CT1
L1
L1
JW7
JW6
JW4
JW8 CF3
L3
L2
CT2
C27
BPF1
+
T1
CF1 CF2
C21
C17
+
+
+
C18
C25
+
RV1
MAIN BOARD
(11)
11
1-862-330-
TP8
(GND)
TP12
(SP OUT)
TP9
(VT)
TP15
(AF GND)
TP13
(FM IN)
TP10 (RF GND)
1
1
10
20
11
2
K
A
A
SP1
GRAY RED RED NATURAL BLK
ANT1
AM FERRITE-ROD
ANTENNA
1
14
1
15
28 3
54
13
54
VOL
A
A
K
KEY BOARD
A
RED
GRY
RED
BLK
GRY
RED
BLK
GRY
RED
GRAY
GRAY
RED
L301
R302
S301
DX/LOCAL BOARD
(11)
11
1-862-331-
ANT2
FM LEAD-WIRE
ANTENNA
FM SENS
LOCAL DX
A
B
C
D
E
1 2 3 4 5 6
•Semiconductor
Location
Ref. No. Location
D1 D-5
D2 C-4
D3 D-4
D4 C-1
IC1 C-3
IC2 C-5
Q1 C-2
Q2 B-2
Q3 D-4
(Page 12)

ICF-M88B
1111
6-2. SCHEMATIC DIAGRAM –TUNER Section – •See page 14 forWaveform. •See page 14 for IC Block Diagrams.
R302
C2 R1
D1
R2
C3
C4
C6 C14
C8
C9
D2
L3 R4 C10
C11
C12
D3
R5
R3
R24 R25
C27
C32
C28
C26
C30 R11
C31
CF3
R10
R9
CF1 CF2
C15
C16 C17 C18
C19
C20
C29
R23
D4
C13
R6 R14
C21
C24
C25
C22
C23
Q3
R13
R12
R8
C34 C37
C36
C39
X1
R17 R21
R20
C42 C43
C44
R19
R7 C45 C46 C47
C38C35 C40
SP1
TP12
TP15
TP8
ANT2
S301
TP13
TP10
CT1
ANT1
L1
CT2
JC4
L2
JC3
JC9
TP9
RV1
IC2
JC10
JC11
JC12
JC5
JC6
Q1
Q2
T1
JC8
IC1
BPF1
4.7
L301
0.1µH
0.01 10k
SVC347
1M
220p
220p
10p 3p
1000p
1000p
HVU202A
22k 7p
1000p
1000p
HVU202A
100k
100k
100k 100k
10
6.3V
0.022
3p
0.01
147
2.2
35V
470
2.2k
0.01
14.7
16V
10
6.3V
0.01
0.22
0.01
4.7k
DAN202UT
4700p
10k 10k
10
6.3V
1
1000
6.3V
470
4V
1
2SA1576
10k
4.7k
2.2k
L4
47µH
470
4V 22p
0.01
22p
75KHz
10k 100k
2.2k
0.1 0.22
2200p
4.7k
2.2k 1100p 0.01
100p4700p 100p
(SP OUT)
(AF GND)
(GND)
(FM IN)
(RF GND)
0
0
0
(VT)
50k
LC72122V
0
0
0
0
0
2SC4081
DTC114TUA
0
CXA1019M
CE
DATA
CLK
DOUT
MUTE
BEEP
VDD
GND
MIX
OUT
F.E
GND
FM
ANT
NC AM
ANT
FM
RF
REG FM
OSC
AFC AM
OSC
VOL NF DISCRI GND
GNDOUT+BFILTERINOUTAGCAGCGNDMETERNCIFINIFINSELECT
BAND AM FM IF AFC(W) AFC(J) DET AF RIPPLE AF
XXVSSAAAPD VSSD VDD FM AM
INININOUT INOUT
CE DI CL DO BAND BO2 BO3 IO1 IO2 IN
IF
ANTENNA
LEAD-WIRE
FM LOCAL
DX
FM SENS
13
2
AM
FERRITE-ROD
ANTENNA AM
OSC
FM
RF
MUTING
VOL
FM/AM PLL
TONE CONTROL
SWITCH
FM/AM BAND
SELECT SWITCH
AM IFT
FM/AM FRONT-END,
FM/AM IF AMP,DET,
AGC,AF AMP
(Page 13)

ICF-M88B
1212
6-3. PRINTED WIRING BOARD – PANEL/POWER SUPPLY Section – : Uses unleaded solder.
C119
S101
S102
T101
+
S107
S104
S105
S108
S109
1
BLK GRY RED
RED GRY BLK RED GRY BLK RED GRY
RED
GRY
8
LCD101
LIQUID CRYSTAL DISPLAY
KEY BOARD
(COMPONENT SIDE)
1-862-332-
R104
R110
R126
C118
(LCD BACK LIGHT)
R109
R129
Q103
BCE
R189
R146
R190
R103
R102
C107
R101
C105
JC102
R108 R105
C108 C122
C104
R144 R145
C102 C128
R138
L101
R128
C136
C142 C141 C140
C126
C146
C135
R179
C138
C124 C125
R139
C139
R143 R140 R178
C133
R106
R112
R107R116
R115
R114
C112
R117
R123
C103
C101
R134
R133
R135
R136
R141
C121
C143
C131
C129
C130
R118
R119
R120
R121
R122
C116
C115
C114
C111
R124
C154
R187
R127
C152
R188
IC102
IC104
D101
D109
KA
KA
D102
KA
IC103
IC101
C157
R184
C156
C149
R182
C155
C158
R183
R180 R111
C117
C109
R185
R186
R181
L104
Q106
Q107
BCE
E
C
B
ECB
Q104
ECB
Q105
IC105
D103
AK
D104
AK
Q101
Q102
BCE
BCE
KEY BOARD
(CONDUCTOR SIDE)
(11)
11
1-862-332-
X102
X101
D106
D105
+
C127
C151
+
DRY BATTERY
SIZE "AA"
(IEC DESIGNATION R6)
2PCS. 3V
SENSOR
UNIT
MAIN
BOARD
A
1
15
16
30
RADIO POWER
RESET
LIGHT
ENTER/SELECT TUNE MODE
BAND/SET
(11)
11
+
–
S103
MODE/FREEZE
S106
12
43
TP115
(KS1)
TP117
(KR3)
TP116
(KS0)
1
20
60
41
21 40
80 61
14
85
12
43
12
43
(LCD BACK LIGHT)
A
B
C
D
E
F
G
H
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
(Page 10)
•Semiconductor
Location
Ref. No. Location
D101 B-14
D102 D-14
D103 B-10
D104 C-10
D105 B-15
D106 B-10
D109 B-14
IC101 C-12
IC102 C-14
IC103 D-14
IC104 D-14
IC105 C-11
Q101 C-9
Q102 C-9
Q103 B-15
Q104 B-12
Q105 B-12
Q106 A-13
Q107 A-13

ICF-M88B
1313
R106
IC105
IC104
IC103
R187
R188
R189
R102
R103
R124
D105
D106
R129R127 C154 R190
D109
C152
D102 R101
R105 R108
R117
C111
C112
R107R112
C108
C122
R115 R114
R116
R118
R119
R120
R121
R122
C114 C115
C116
C128
C104
X102
R138
C103
C101 D101
R128 R140 R143
R178 R179
C133 C135
Q104
R134
C121
R139
C129
C131
C130
X101
C136
C138
C139
R141
C146
R133
R135
R136
C124
C125
C126
R180
R181
R182
R183
R184
R185 R186
R126
C151
D103 R104
C109 Q101 Q102
D104R109 C117
R110
R111 C118 C119
Q107
R146
C140
C141
C142
C143
C155C158
C156
C157
R123
Q106
LCD101
IC101
Q103
C105
JC102
IC102
C127
C102
TP117
Q105
S105S104
S101 S102
S109S108S107
R145
C107
T101
R144
C149
S103
S106
TP116
TP115
10k
S-80817CNNB
S-80819CNNB
S-80821CNNB
1k
1k
1k
470k
470k
100k
SLI-343OUT
SLI-343OUT
100100 0.1 10k
RB520
0.01
1SS355 2.2M
1M 1M
1k
0.01
0.1
1k1k
100p
0.01
470k 10k
10k
1k
1k
1k
1k
1k
100p 100p
4700p
22p
22p
32.768KHz
220k
1
1
L101
22µH
L104
100µH
RB521S
1M 10k 10k
100k 100k
0.01 0.01
2SA1576
1M
1
1M
10p
10p
22p
4.19MHz
22p
22p
9p
10k
0.01
2.2k
2.2k
2.2k
470p
470p
470p
2.2k
2.2k
2.2k
2.2k
2.2k
2.2k 2.2k
220
2.2
35V
1SS355 1k
10p 2SC4081 2SC4081
UDZSTE-1713B100k 0.1
100k
47k 1 10
6.3V
2SB970
470k
1
1
1
1
1000p1000p
1000p
1000p
1k
DTC144TUA
-8BT
µPD789488GC-A35
2SA1576
0.1
0
BR24L01F-WE2
0.047F
5.5V
6p
(KR3)
2SA1576
100k
0.01
1k
100p
(KS0)
(KS1)
COM0
COM1
COM2
COM3
COM0
COM1
COM2
COM3
S0
S1
S2
S3
S4
S5
S6
S7
S8
S9
S10
S0
S1
S2
S3
S4
S5
S6
S7
S8
S9
S10
LIQUID CRYSTAL DISPLAY
GND
GND
GND
GND
IN
OUT
IN
OUT
VCC
WP
CLK
DATA
A0
A1
A2
GND
P65
P64
P63
P62
P61
P60
AVSS
VDET2
VDET1
BEEP
PS
MOUNT
MUTE
P24
P10
CE/PLL
CLK/PLL
DATA/PLL
CLK/EEPRON
DATA/EEPROM
P07
POWER
LED
KR3
KR2
KR1
KR0
P00
IC0
XT1
XT2
VDD
VSS
X1
X2
RESET
SHIFT
KS2
KS1
KS0
P66
VERSION
AVDD
P87
P86
S25
S24
S23
S22
S21
S20
S19
S18
S17
S16
S15
S14
S13
S12
S11
S10
S9
S8
S7
S6
S5
S4
S3
S2
S1
S0
COM3
COM2
COM1
COM0
VLC0
VLC1
VLC2
CAPL
CAPH
GND
GND
IN
OUT
CE
DATA
CLK
DOUT
MUTE
BEEP
VDD
GND
SYSTEM CONTROLLER
SENSOR
UNIT (LCD BACK LIGHT)
D105,106
VOLTAGEDETECT
VOLTAGEDETECT
EEPROM
SHIFT
CLOCK
SHIFT
CLOCK
+-
RESET
TUNE MODE ENTER/SELECT
MODE/FREEZE
LIGHTBAND/SET RADIO POWER
DRY BATTERY
SIZE"AA"
(IEC DESIGNATION R6)
DC/DC
CONVERTER
DC/DC
CONVERTER
Q101,102
Q106,107
POWER ON/OFF
CONTROL SWITCH
LED DRIVE
2PCS. 3V
RESET SIGNAL
GENERATOR
•TOTAL CURRENT
FM: 18mA
AM: 11mA
(NO-SIGNAL CONDITION)
6-4. SCHEMATIC DIAGRAM – PANEL/POWER SUPPLY Section – •See page 14 for Waveforms. •See page 15 for IC Pin Function Description.
(Page 11)

ICF-M88B
1414
263 ns
1.2 Vp-p
263 ns
1.9 Vp-p
239 ns
2.2 Vp-
p
30.5 µ s
2.5 Vp-p
•Waveforms
– MAIN Board –
13.3 µ s
1.1 Vp-p
1 V/DIV, 10 µ s/DIV
1 V/DIV, 100 ns/DIV
1 V/DIV, 100 ns/DIV
500 mV/DIV, 100 ns/DIV
– KEY Board –
500 mV/DIV, 5 µ s/DIV
IC101 ua (XT2)
qs IC101 ug (X2)
qd Q101 (Collector)
qf Q101 (Base),
Q102 (Collector)
qa
IC2 w; (X OUT)
1
•IC Block Diagrams
– MAIN Board –
IC1 CXA1019M-T6
IC2 LC72122V-TLM-E
FM FE
TUNING METER
AM IF DET AGC
AF POWER AMP
FM IF
FM/AM IF OUT FM RF IN FE GND
NC
AM RF IN FM RF FM OSC REG OUT AFC AM OSC NF VOL FM DISCRI GND
FM/AM BAND
SELECT
FM IF IN
AM IF IN
NC
METER
IF GND
DET OUT
AFC AGC
AFC AGC
AF IN
RIPPLE FILTER
AF OUT
VCC
GND
AM FE
FM
DISCRIMINATOR
14 13 11 987 216 5 34
15 16 17 18 19 20 21 22 23 24 25 26 27 28
12 10
11
10
9
8
7
6
5
4
3
2
1
12
13
14
15
19
20
UNLOCK
DETECTOR
POWER ON
RESET
UNIVERSAL
COUNTER
CCB
I/F
CE
DI
CL
DO XOUT
AOUT
XIN
AIN
PD
VSS
VDD
FMIN
AMIN
B01
B02
B03
I01
I02
IFIN
PHASE
DETECTOR
CHARGE
PUMP
REFERENCE
DIVIDER
SWALLOW
COUNTER
1/16,1/17
4BITS
12BITS
PROGRAMMABLE
DIVIDER
DATA SHIFT REGISTER
LATCH
1/2
16
17
18 VSSA

15
ICF-M88B
•IC Pin Function Description
KEY BOARD IC101 µPD789488GC-A35-8BT (SYSTEM CONTROLLER)
Pin No. Pin Name I/O Description
1, 2 CAPH, CAPL — Terminal for doubler circuit capacitor connection to develop liquid crystal display drive voltage
3 to 5 VLC2 to VLC0 — Terminal for doubler circuit capacitor connection to develop liquid crystal display drive voltage
6 to 9 COM0 to COM3 O Common drive signal output to the liquid crystal display
10 to 35 S0 to S25 O Segment drive signal output to the liquid crystal display
36, 37 P86, P87 O Not used
38 AVDD — Power supply terminal (+2.41V) (for A/D converter)
39 VERSION I Setting terminal for the destination Fixed at “H” in this set
40 to 46 P66 to P60 I Not used
47 AVSS — Ground terminal (for A/D converter)
48 VDET2 I Voltage detection signal input terminal “L”: 2.1V or less
49 VDET1 I Voltage detection signal input terminal “L”: 1.9V or less
50 BEEP O Beep sound output to the FM/AM front-end
51 PS I Pulse signal input terminal for 1 rotation time measurement
52 MOUNT I Mount state detection signal input terminal “L”: mount connected, “H”: no connected
53 MUTE O Radio output muting on/off control signal output terminal “L”: muting on
54 P24 O Not used
55 DATA/EEPROM I/O Two-way data bus with the EEPROM
56 CLK/EEPROM O Serial clock signal output to the EEPROM
57 DATA/PLL O Serial data output to the FM/AM PLL
58 CLK/PLL O Serial clock signal output to the FM/AM PLL
59 CE/PLL O Chip enable signal output to the FM/AM PLL
60, 61 P10, P07 O Not used
62 POWER O Radio power on/off control signal output terminal “H”: power on
63 LED O LED drive signal output of the liquid crystal display back light “L”: LED on
64 KR3 I Key return signal input terminal Not used
65 to 67 KR2 to KR0 I Key return signal input terminal
68 P00 O Not used
69 IC0 — Connected to the ground
70 XT1 I Sub system clock input terminal (32.768 kHz)
71 XT2 O Sub system clock output terminal (32.768 kHz)
72 VDD — Power supply terminal (+2.4V)
73 VSS — Ground terminal
74 X1 I Main system clock input terminal (4.19 MHz)
75 X2 O Main system clock output terminal (4.19 MHz)
76 RESET I System reset signal input from the reset signal generator “L”: reset
For several hundreds msec. after the power supply rises, “L” is input, then it changes to “H”
77 SHIFT O Shift clock on/off control signal output terminal “L”: shift clock on
78 to 80 KS2 to KS0 O Key source signal output terminal

16
ICF-M88B SECTION 7
EXPLODED VIEWS
7-1. CABINET (UPPER) SECTION
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
1A-4578-032-A BUTTON ASSY
21-786-739-11 SWITCH, RUBBER KEY
3A-4578-030-A CABINET (UPPER) ASSY
43-254-083-01 SCREW
52-059-726-01 + TAPPING SCREW P1.7X10
SP1 1-825-832-11 SPEAKER (5.0cm)
•Items marked “*” are not stocked since they
are seldom required for routine service. Some
delay should be anticipated when ordering
these items.
•The mechanical parts with no reference
numberin the explodedviewsare not supplied.
NOTE:
•-XX and -X mean standardized parts, so they
may have some difference from the original
one.
•Color Indication of Appearance Parts
Example:
KNOB, BALANCE (WHITE) . . . (RED)
↑↑
Parts Color Cabinet's Color
1
2
3
4
5
5
not supplied
cabinet (lower) section
chassis section
SP1

17
ICF-M88B
7-2. CHASSIS SECTION
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
51 3-254-083-01 SCREW
52 A-4547-686-A MAIN BOARD, COMPLETE
53 3-267-227-01 CHASSIS
54 A-4547-690-A KEY BOARD, COMPLETE
55 1-780-143-11 CONDUCTIVE BOARD, CONNECTION
56 3-267-229-01 HOLDER (LCD)
57 3-267-252-01 SHIELD (LCD)
58 2-059-727-01 SHEET, REFLECTOR
59 3-267-254-01 SHIELD (DD), A
60 2-055-147-01 SHIELD (DD), B
61 3-267-233-01 LEVER, JOG
62 2-176-535-01 SHEET (A), REFLECTION
63 2-177-240-01 SHEET, LIGHT INTERCEPTION
64 2-177-241-01 SHEET (BOTTOM), REFLECTION
65 2-177-764-01 SHEET (B), LIGHT INTERCEPTION
ANT1 1-456-789-11 COIL, FERRITE-ROD ANTENNA (MW)
LCD101 1-805-611-11 DISPLAY PANEL, LIQUID CRYSTAL
51
51
52
53
54
55
60
59 58
64
62
63 55
57
65
61
ANT1
LCD101
KEY board

18
ICF-M88B
7-3. CABINET (LOWER) SECTION
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
101 A-4578-031-A CABINET (LOWER) ASSY
102 3-267-238-01 CASE (LOWER), ANTENNA
103 3-267-261-01 SPRING (ANTENNA)
104 2-025-137-01 SCREW (1.4X4)
105 3-267-236-01 KNOB (DX/LOCAL)
107 2-059-726-01 + TAPPING SCREW P1.7X10
108 3-267-231-01 LID (MIDDLE), BATTERY CASE
109 3-267-246-01 HOOK (BATTERY CASE LID)
110 3-267-260-01 SPRING (BATTERY CASE LID)
111 3-236-793-01 O RING (VOL)
112 3-267-235-01 KNOB (VOL)
113 3-267-237-01 CASE (UPPER), ANTENNA
114 3-265-204-01 WASHER, POLYETHYLENE
115 3-267-234-01 ADAPTOR
116 3-267-262-01 RING (BATTERY CASE LID), O
117 3-254-083-01 SCREW
118 7-626-308-61 SPRING-PIN 1.4X14
101 113
103
104
104
116
118
105
115
107
117
108
109
110
114
112
102
111
not supplied
not supplied
not supplied
(DX/LOCAL board)

19
ICF-M88B
Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
DX/LOCAL BOARD
***************
< COIL >
L301 1-412-967-31 INDUCTOR 0.1uH
< RESISTOR >
R302 1-216-793-11 METAL CHIP 4.7 5% 1/10W
< SWITCH >
S301 1-570-675-11 SWITCH, SLIDE (FM SENS)
*************************************************************
A-4547-690-A KEY BOARD, COMPLETE
********************
1-780-143-11 CONDUCTIVE BOARD, CONNECTION
2-055-147-01 SHIELD (DD), B
2-059-727-01 SHEET, REFLECTOR
3-267-229-01 HOLDER (LCD)
3-267-252-01 SHIELD (LCD)
3-267-254-01 SHIELD (DD), A
< CAPACITOR >
C101 1-115-156-11 CERAMIC CHIP 1uF 10V
C102 1-162-911-11 CERAMIC CHIP 6PF 0.5PF 50V
C103 1-115-156-11 CERAMIC CHIP 1uF 10V
C104 1-162-919-11 CERAMIC CHIP 22PF 5% 50V
C105 1-164-156-11 CERAMIC CHIP 0.1uF 25V
C107 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C108 1-162-927-11 CERAMIC CHIP 100PF 5% 50V
C109 1-162-915-11 CERAMIC CHIP 10PF 0.5PF 50V
C111 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C112 1-164-156-11 CERAMIC CHIP 0.1uF 25V
C114 1-162-927-11 CERAMIC CHIP 100PF 5% 50V
C115 1-162-927-11 CERAMIC CHIP 100PF 5% 50V
C116 1-162-968-11 CERAMIC CHIP 0.0047uF 10% 50V
C117 1-164-156-11 CERAMIC CHIP 0.1uF 25V
C118 1-115-156-11 CERAMIC CHIP 1uF 10V
C119 1-126-157-11 ELECT 10uF 20% 16V
C121 1-115-156-11 CERAMIC CHIP 1uF 10V
C122 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C124 1-162-962-11 CERAMIC CHIP 470PF 10% 50V
C125 1-162-962-11 CERAMIC CHIP 470PF 10% 50V
C126 1-162-962-11 CERAMIC CHIP 470PF 10% 50V
C127 1-125-701-11 DOUBLE LAYER 0.047F 5.5V
C128 1-162-919-11 CERAMIC CHIP 22PF 5% 50V
C129 1-162-915-11 CERAMIC CHIP 10PF 0.5PF 50V
C130 1-162-919-11 CERAMIC CHIP 22PF 5% 50V
C131 1-162-915-11 CERAMIC CHIP 10PF 0.5PF 50V
C133 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C135 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C136 1-162-919-11 CERAMIC CHIP 22PF 5% 50V
C138 1-162-919-11 CERAMIC CHIP 22PF 5% 50V
C139 1-162-914-11 CERAMIC CHIP 9PF 0.5PF 50V
C140 1-115-156-11 CERAMIC CHIP 1uF 10V
C141 1-115-156-11 CERAMIC CHIP 1uF 10V
C142 1-115-156-11 CERAMIC CHIP 1uF 10V
C143 1-115-156-11 CERAMIC CHIP 1uF 10V
C146 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C149 1-162-927-11 CERAMIC CHIP 100PF 5% 50V
C151 1-124-257-00 ELECT 2.2uF 20% 35V
C152 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C154 1-164-156-11 CERAMIC CHIP 0.1uF 25V
C155 1-162-964-11 CERAMIC CHIP 0.001uF 10% 50V
C156 1-162-964-11 CERAMIC CHIP 0.001uF 10% 50V
C157 1-162-964-11 CERAMIC CHIP 0.001uF 10% 50V
C158 1-162-964-11 CERAMIC CHIP 0.001uF 10% 50V
< DIODE >
D101 8-719-071-34 DIODE RB521S-30-TE61
D102 8-719-988-61 DIODE 1SS355TE-17
D103 8-719-988-61 DIODE 1SS355TE-17
D104 8-719-083-63 DIODE UDZSTE-1713B
D105 8-719-083-10 LED SLI-343DUT32 (LCD BACK LIGHT)
D106 8-719-083-10 LED SLI-343DUT32 (LCD BACK LIGHT)
D109 8-719-069-29 DIODE RB520S-30TE61
< IC >
IC101 6-804-545-01 IC uPD789488GC-A35-8BT
IC102 6-703-769-01 IC BR24L01AF-WE2
IC103 6-703-324-01 IC S-80821CNNB-B8GT2G
IC104 6-705-588-01 IC S-80819CNNB-B8ET2G
IC105 6-705-589-01 IC S-80817CNNB-B8CT2G
< SHORT >
JC102 1-216-864-11 SHORT CHIP 0
SECTION 8
ELECTRICAL PARTS LIST
NOTE:
•Due to standardization, replacements in the
parts list may be different from the parts
specified in the diagrams or the components
used on the set.
•-XX and -X mean standardized parts, so they
may have some difference from the original
one.
•RESISTORS
All resistors are in ohms.
METAL: Metal-film resistor.
METAL OXIDE: Metal oxide-film resistor.
F: nonflammable
•Items marked “*” are not stocked since they
are seldom required for routine service.
Some delay should be anticipated when
ordering these items.
•SEMICONDUCTORS
In each case, u: µ, for example:
uA... : µA... uPA... : µPA...
uPB... : µPB... uPC... : µPC...
uPD... : µPD...
•CAPACITORS
uF: µF
•COILS
uH: µH
When indicating parts by reference
number, please include the board.
DX/LOCAL KEY

Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark
20
ICF-M88B
< COIL >
L101 1-412-995-21 INDUCTOR 22uH
L104 1-412-963-11 INDUCTOR 100uH
< LIQUID CRYSTAL DISPLAY >
LCD101 1-805-611-11 DISPLAY PANEL, LIQUID CRYSTAL
< TRANSISTOR >
Q101 8-729-905-35 TRANSISTOR 2SC4081-R
Q102 8-729-905-35 TRANSISTOR 2SC4081-R
Q103 8-729-026-52 TRANSISTOR 2SA1576A-T106-R
Q104 8-729-026-52 TRANSISTOR 2SA1576A-T106-R
Q105 8-729-026-52 TRANSISTOR 2SA1576A-T106-R
Q106 8-729-029-15 TRANSISTOR DTC144TUA-T106
Q107 8-729-046-89 TRANSISTOR 2SB970-S (TX).S0
< RESISTOR >
R101 1-216-861-11 METAL CHIP 2.2M 5% 1/10W
R102 1-216-853-11 METAL CHIP 470K 5% 1/10W
R103 1-216-853-11 METAL CHIP 470K 5% 1/10W
R104 1-216-821-11 METAL CHIP 1K 5% 1/10W
R105 1-216-857-11 METAL CHIP 1M 5% 1/10W
R106 1-216-833-11 METAL CHIP 10K 5% 1/10W
R107 1-216-821-11 METAL CHIP 1K 5% 1/10W
R108 1-216-857-11 METAL CHIP 1M 5% 1/10W
R109 1-216-845-11 METAL CHIP 100K 5% 1/10W
R110 1-216-845-11 METAL CHIP 100K 5% 1/10W
R111 1-216-841-11 METAL CHIP 47K 5% 1/10W
R112 1-216-821-11 METAL CHIP 1K 5% 1/10W
R114 1-216-833-11 METAL CHIP 10K 5% 1/10W
R115 1-216-853-11 METAL CHIP 470K 5% 1/10W
R116 1-216-833-11 METAL CHIP 10K 5% 1/10W
R117 1-216-821-11 METAL CHIP 1K 5% 1/10W
R118 1-216-821-11 METAL CHIP 1K 5% 1/10W
R119 1-216-821-11 METAL CHIP 1K 5% 1/10W
R120 1-216-821-11 METAL CHIP 1K 5% 1/10W
R121 1-216-821-11 METAL CHIP 1K 5% 1/10W
R122 1-216-821-11 METAL CHIP 1K 5% 1/10W
R123 1-216-821-11 METAL CHIP 1K 5% 1/10W
R124 1-216-845-11 METAL CHIP 100K 5% 1/10W
R126 1-216-813-11 METAL CHIP 220 5% 1/10W
R127 1-216-809-11 METAL CHIP 100 5% 1/10W
R128 1-216-857-11 METAL CHIP 1M 5% 1/10W
R129 1-216-809-11 METAL CHIP 100 5% 1/10W
R133 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R134 1-216-857-11 METAL CHIP 1M 5% 1/10W
R135 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R136 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R138 1-216-849-11 METAL CHIP 220K 5% 1/10W
R139 1-216-857-11 METAL CHIP 1M 5% 1/10W
R140 1-216-833-11 METAL CHIP 10K 5% 1/10W
R141 1-216-833-11 METAL CHIP 10K 5% 1/10W
R143 1-216-833-11 METAL CHIP 10K 5% 1/10W
R144 1-216-821-11 METAL CHIP 1K 5% 1/10W
R145 1-216-845-11 METAL CHIP 100K 5% 1/10W
R146 1-216-853-11 METAL CHIP 470K 5% 1/10W
R178 1-216-845-11 METAL CHIP 100K 5% 1/10W
R179 1-216-845-11 METAL CHIP 100K 5% 1/10W
R180 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R181 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R182 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R183 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R184 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R185 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R186 1-216-825-11 METAL CHIP 2.2K 5% 1/10W
R187 1-216-821-11 METAL CHIP 1K 5% 1/10W
R188 1-216-821-11 METAL CHIP 1K 5% 1/10W
R189 1-216-821-11 METAL CHIP 1K 5% 1/10W
R190 1-216-833-11 METAL CHIP 10K 5% 1/10W
< SWITCH >
S101 1-554-088-00 SWITCH, KEY BOARD (–)
S102 1-554-088-00 SWITCH, KEY BOARD (+)
S104 1-554-088-00 SWITCH, KEY BOARD (TUNE MODE)
S105 1-554-088-00 SWITCH, KEY BOARD (ENTER SELECT)
S107 1-554-088-00 SWITCH, KEY BOARD (BAND/SET)
S108 1-554-088-00 SWITCH, KEY BOARD (LIGHT)
S109 1-554-088-00 SWITCH, KEY BOARD (RADIO POWER)
< TRANSFORMER >
T101 1-439-578-11 TRANSFORMER, DC/DC CONVERTER
< VIBRATOR >
X101 1-813-175-11 VIBRATOR, CERAMIC (4.19MHz)
X102 1-760-252-12 VIBRATOR, CRYSTAL (32.768kHz)
*************************************************************
A-4547-686-A MAIN BOARD, COMPLETE
*********************
< BAND PASS FILTER >
BPF1 1-236-711-21 FILTER, BAND PASS
< CAPACITOR >
C2 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C3 1-164-230-11 CERAMIC CHIP 220PF 5% 50V
C4 1-164-230-11 CERAMIC CHIP 220PF 5% 50V
C6 1-162-915-11 CERAMIC CHIP 10PF 0.5PF 50V
C8 1-162-964-11 CERAMIC CHIP 0.001uF 10% 50V
C9 1-162-964-11 CERAMIC CHIP 0.001uF 10% 50V
C10 1-162-912-11 CERAMIC CHIP 7PF 0.5PF 50V
C11 1-115-416-11 CERAMIC CHIP 0.001uF 5% 25V
C12 1-115-416-11 CERAMIC CHIP 0.001uF 5% 25V
C13 1-162-968-11 CERAMIC CHIP 0.0047uF 10% 50V
C14 1-162-908-11 CERAMIC CHIP 3PF 0.25PF 50V
C15 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C16 1-115-156-11 CERAMIC CHIP 1uF 10V
C17 1-124-259-11 ELECT 4.7uF 20% 50V
C18 1-126-157-11 ELECT 10uF 20% 16V
C19 1-162-970-11 CERAMIC CHIP 0.01uF 10% 25V
C20 1-165-128-11 CERAMIC CHIP 0.22uF 16V
C21 1-126-157-11 ELECT 10uF 20% 16V
C22 1-126-518-11 ELECT 470uF 20% 4V
MAINKEY