Sony ICF-C1200 Service Manual ▷ View online
4
ICF-C1200
SECTION 3
ELECTRICAL ADJUSTMENTS
BAND button : AM
Volume : MIN
Volume : MIN
3-1.TUNER SECTION
AM Section
FM Section
BAND button : FM
Volume : MIN
Volume : MIN
Put the lead-wire
antenna close to
the set.
antenna close to
the set.
AM RF signal
generator
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
signal.
Output level : as low as possible
telescopic
antenna
terminal
antenna
terminal
FM RF signal
generator
generator
22.5kHz frequency deviation by
400Hz signal.
Output level : as low as possible
400Hz signal.
Output level : as low as possible
0.01 uF
Adjustment Location : Main board (See page 5)
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
done by the trimmer capacitors.
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T101
1485kHz
<
1480kHz
>
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust part
Frequency display
L105
531kHz <530kHz>
reading on digital
voltmeter.
Adjustment value: 2.7V
Standaed value: 2.5 to 2.9V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L 102
585kHz <580kHz>
CT101
1,485kHz <1,480kHz>
Frequency Coverage Adjustment
Connect Location :
FM FREQUENCY COVERAGE CONFIRMATION
Adjust part Frequency display
Confirmation
87.5MHz
3.0 to 4.0V
Confirmation
108MHz
9.5 to 10.5V
reading on digital
voltmeter
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L103
87.5MHz
CT102
108MHz
32
Ω
level meter
set
J201 (phones)
+
–
0dB=1
µV
< > : US model
MAIN BOARD (SIDE A)
S308
(JOG SWITCH)
BAT401
PAS
TP
(VT)
C405
R404
C412
R403
R314
R315
R315
R405
C404
C301
C406
C407
R401
R402
D402
D403
BCE
Q402
B
Q
302
E
CB
T401
+
–
Digital
TP
(VT)
100K
Ω
voltmeter
5
ICF-C1200
1-
C113
C108
CF101
L104
L101
C212
C202
C118
T101
C201
C207
C205
R204
C103
C211
C214
C213
C206
C204
C410
R113
R129
R112
R202
R205
R201
R203
BCE
Q201
BCE
Q202
C210
C215
C208
C203
C209
C120
C122
D108
CT102
IC201
1
5
8
16
12
9
D109
TP
(3V)
TP
(76K)
+
+
33k
Ω
TP1 (76k)
TP(3V)
1
µ
F
frequency
counter
counter
MAIN BOARD (SIDE A)
VCO Adjustment
Procedure :
Procedure :
FM RF signal
generator
generator
Carrier frequency : 98MHz
Modulation : No modulation
Output level : 1.38mV (–55dB)
Modulation : No modulation
Output level : 1.38mV (–55dB)
set
telescopic
antenna
terminal
antenna
terminal
0.01 F
µ
1. Connect the frequency counter to TP (76k) and TP (3V) as shown
the figure below.
2. Turn the set to 98MHz.
3. Adjust RV101 for 76kHz reading frequency counter.
3. Adjust RV101 for 76kHz reading frequency counter.
Standard value:75.5kHz to 76.5kHz.
Adjustment Location:
[MAIN BOARD] (SIDE A)
CT101: AM Tracking Adjustment
L102: AM Tracking Adjustment
L105: AM Frequvency Coverage Adjustment
RV101: VCO Adjustment
T101: AM IF Adjustment
L103: FM Tracking Adjustment
CT102: FM Tracking Adjustment
6
ICF-C1200
Pin No.
Pin name
I/O
Description
1-4
COM1-4
O
LCD common output.
5-26
S1-S22
O
LCD segment output.
27
HOLD SW
I
HOLD switch input. ON:L OFF:H
28-30
KR1-3
I
Key return input.
31
VDD
—
Power supply terminal.
32-34
KR1-3
O
Key souce output.
35
POWER
O
Power ON control signal output. ON:L OFF:H
36
BEEP
O
Beep signal output.
37
MUTE
O
Mute signal output.
38
WAKE UP
O
Alarm output at volume control min. ON:L OFF:H
39
LCD
I
LCD check test mode setting input.
40
BAND
O
Band select signal output. AM:H FM:L
41
TEST
—
Not used (Fixed at "L").
42
HOLD
—
Not used (Fixed at "L").
43
INTR1
I
1.9V voltage detection terminal. Radio OFF :L
44
INTR2
I
1.1V voltage detection terminal. All OFF :L
45
—
Not used (OPEN).
46
—
Not used (OPEN).
47
GND
—
Ground terminal.
48
FM IN
I
FM local oscillator signal input.
49
AM IN
I
AM local oscillator signal input.
50
VDD
—
Power supply terminal.
51
D01
—
Not used (OPEN).
52
D02
O
Tuning voltage control output.
53
VREG
—
Regulator output for phase compalator.
54
—
Not used (OPEN).
55
AL SW1
I
ALARM switch input (OFF).
56
AL SW2
I
ALARM switch input (RADIO).
57
AL SW3
I
ALARM switch input (BUZZER).
58
VDET
I
2.1V voltage detection input.
59
ID
I
Destination select input.
60
ID
I
Destination select input.
61
—
Not used (OPEN).
62
SP BEEP
O
Beep signal output.
63
LIGHT
O
LCD back light ON/OFF output.
64
ST/MO
O
Stereo/Mono select output.
65-69
—
Not used (OPEN).
70
RESET
I
Reset signal input.
71
XOUT
O
Oscillator output (75kHz).
72
XIN
I
Oscillator input (75kHz).
73
GND
—
Ground terminal.
74
VDB
—
Capacitor terminal.
75
C1
—
Capacitor terminal.
76
C2
—
Capacitor terminal.
77
VEE
—
Voltage pull-up terminal.
78
C3
—
Capacitor terminal.
79
C4
—
Capacitor terminal.
80
VLCD
—
Voltage pull-up terminal.
SECTION 4
DIAGRAMS
4-1. EXPLANATION OF IC TERMINALS
• IC301 TC9328AF-SR7491
(System control, LCD driver)
(System control, LCD driver)
7
7
ICF-C1200
4-2. BLOCK DIAGRAMS
• Signal path.
F
: Analog
f
: Digital
• Abbreviation
JE
: Tourist
D401
BAT401
RV201
T101
X301
KS1
KS2
KS3
KR1
KR2
KR3
T401
Q104
D106
D107
RV101
Q103
D402
Q101
D101
D103
D104
D102
CF102
CF103
CF101
J201
D303
D304
Q201
Q202
PAS
75kHz
BAND
SELECT
AM_IF
IN
IN
FM_IF
IN
IN
L_CH
R_CH
REG
FM_OSC
AM_OSC
MPX REG
PLL
LPF
FM/AM
DET,FM MPX
FRONT-END,IF AMP,
TELESCOPIC
ANTENNA
SPEAKER
AM
IF
VCO
COVERAGE
AM FREQUENCY
FM FREQUENCY
COVERAGE
AM TRACKING
FM/AM
FE OUT
FM RF IN
AM RF IN
FM RF
PILOT
DET
LPF2
CT101
HOLD SW
POW
ER
BEEP
MUTE
WAKEUP
BAND
INTR1
INTR2
FM
IN
AM
IN
DO2
VDET
ID
ID
AL SW1
AL SW2
AL SW3
AL SW2
AL SW3
LIGHT
RESET
XOUT
XIN
SP BEEP
ST/M
O
DISPLAY
LIQUID
CRYSTAL
FERRITE-BAR
AM
ANTENNA
L102
CT102
FM TRACKING
L102,CT101
L105
LCD301
VOL
AM
AM
OSC
FRONT-END
OSC
FRONT-END
FM
FM
VREF
AM
OSC
L105
OSC
L104
L104
VREF
LPF1
VCO
MPX
REG
REG
MPX,
DECODER
AMP
FM IF/
DISCRI
DISCRI
AM IF/
DET
DET
PILOT
S22
S1
COM
0
COM
4
VCC
AM
RF
FM
FM
RF
RF
( )
( )
( )
( )
L103,CT102
L103
+
SP101
ANT101
IN1
REG
VOL
OUT1
OUT2
IN2
SYSTEM
CONTROL
BUFFER
DC-DC
CONVERTER
Q401,402
LED DRIVER
LCD
BACK LIGHT
D301,302
( )
SPEAKER
BEEP
BEEP
+B SWITCH
Q403,404
DETECT
DETECT
1.1V VOLTAGE
1.9V VOLTAGE
DETECT
2.1V VOLTAGE
RESET
POWER AMP
VOL,
DRY BATTERY
2PCS,3V
ON
OFF
HOLD
(IEC DESIGNATION R03)
SIZE"AAA"
BATT
VCC
BACK
UP
+1.5V REG
(+1.2V)
IC401
S311
ALARM
MODE
OFF
RADIO
BUZZER
KEY MATRIX
S302-310
LPF
Q102
REG
VOL
POWER AMP
POWER AMP
Q203,204
GATE
Q206
BATT
REG
IC201
Q303
AEP,E
US,JE
US,AEP,E
JE
BACK UP
-
-
1
4
5
26
BACK UP
Q205
BACK UP
BATT
BATT
IC301
IC305
IC304
IC302
IC303
IC101
Q302