Sony ICF-C900HS Service Manual ▷ View online
– 5 –
2
power cord
1
transformer (T102)
power cord
FM wire antenna
1
pointer
2
3
6
three claws
4
knob (tuning)
When installing, knob (tuning) adjust the
marking (B) hole and pointer boss.
When installing, knob (tuning) adjust the
marking (B) hole and pointer boss.
5
Turn variable capacitor
(CV1) shaft and
knob (tuning) in the
arrow direction fully.
(CV1) shaft and
knob (tuning) in the
arrow direction fully.
boss
B
7
MAIN board
variable capacitor
(CV1)
(CV1)
knob (tuning)
marking (B) hole
TRANSFORMER (T102)
DIAL POINTER SETING
Note:
Follow the assembly procedure in the numerical order given.
Note:
When installing, position the power coad as shown in the figure.
– 6 –
SECTION 3
ELECTRICAL ADJUSTMENTS
TUNER SECTION
[FM]
Setting:
BAND switch: FM
BAND switch: FM
[AM]
Setting:
BAND switch: AM
BAND switch: AM
• 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.
FM RF signal
generator
generator
400 Hz, 30% FM modulation
frequency deviation
frequency deviation
±
22.5 kHz
Output level: as low as possible
MAIN board
TP (FMIN)
TP (FMIN)
0.01
µ
F
AM RF signal
generator
generator
400 Hz, 30%
AM modulation
Output level: as low as possible
AM modulation
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
antenna close to
the set.
level meter
8
Ω
+
–
–
MAIN board
TP (SP-OUT)
TP (SP-OUT)
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter.
L3
86.5 MHz
CT1-3
109.5 MHz
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L2
86.5 MHz
CT1-2
109.5 MHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter.
L4
520 kHz
CT1-4
1,650 kHz
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L1
600 kHz
CT1-1
1,400 kHz
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T1
455 kHz
DATA TX SECTION
DATA TRANSMISSION LEVEL ADJUST
Setting:
RANDOM switch: OFF
RANDOM switch: OFF
Schematic Diagrams of the filter unit:
Adjusting Procedure:
1. Insert the AC plug of set into the AC Outlet of filter unit while
1. Insert the AC plug of set into the AC Outlet of filter unit while
pressing
[D.S.T SUMMER T]
,
[CLOCK]
,
[SNOOZE/DATE/SLEEP OFF]
buttons simultaneously.
2. All LCD segment are turned on, and the test mode will start.
3. Press all button one by one as below,
3. Press all button one by one as below,
[D.S.T SUMMER T]
,
[CLOCK]
,
[TIME SET–]
,
[TIME SET+]
[ALARM A]
,
[ALARM B]
,
[LIGHT 1]
,
[LIGHT 2]
[SNOOZE/DATE/SLEEP OFF]
,
[RADIO OFF, ALARM SET]
[RADIO ON, SLEEP]
4. Set
[RANDOM]
Switch to OFF
n ON n OFF position, and
the display “OFF TIME0*” are appear.
5. Press
[1]
button to blink the display “OFF TIME*” and the
carrier signal output continuity,
(*: ID code No.)
(*: ID code No.)
6. Adjust T2 to 0.45 V observing AC voltmeter.
Adjustment Value:
Adjustment part
STANDARD VALUE
T2
0.35 V to 0.55 V
7. To exit from test mode, disconnect the power cord of set.
filter unit
AC voltmeter
AC outlet
measure
terminal
terminal
AC120 V, 60 Hz
set
+
–
–
AC outlet
measure
terminal
terminal
11
Ω
62
Ω
0.1
µ
F
0.1
µ
F
1 mH
1 mH
– 7 –
Adjustment Location:
CT1-3
[MAIN Board] (Component Side)
SW1 Band
T1
AM IF Adjustment
L2
CT1-2
FM Tracking
Adjustment
Adjustment
L3
FM Frequency
Coverage Adjustment
Coverage Adjustment
L1
CT1-1
AM Tracking
Adjustment
Adjustment
CT1-4
L4
AM Frequency
Coverage Adjustment
Coverage Adjustment
RV1
T2
DATA TRANSMISSION LEVEL
Adjustment
[MAIN Board] (Conductor Side)
IC2
IC1
CN2
SW1
TP
(SP-OUT)
TP
(FMIN)
– 8 –
– 9 –
4-1.
BLOCK DIAGRAM
SECTION 4
DIAGRAMS
13
10
15
18
11
6
8
FM
FRONT-END
FM
IF AMP
FM
DISCRIMINATOR
AF POWER
AMP
AM IF, AGC,
DET
AM
FRONT-END
MUTING
Q1
POWER CONTROL
Q4, 5, 8 – 10
DATA TRANSMISSION
LEVEL
RECT
D5, 6
D5, 6
RECT
D11
+4V
REGULATOR
Q6
B+ SWITCH
(FOR BACK UP)
Q7
B+ SWITCH
Q2, 3
17
FM RF
IN
IN
FM/AM
IF OUT
CF3
CF2
CF1
T1
AM IF
FM
RF
RF
3
FM
IF IN
IF IN
FM
DISCRI
DISCRI
24
25
DET
OUT
AF
IN
IN
29
AF
OUT
SP1
(SPEAKER)
5
4
32
34
46
5
AM
IF IN
IF IN
16
BAND
SELECT
NF
ALM
MUTE
3
SO1
SEG11
SO3
6
SO4
7
P1
8
P2
9
P3
27
M1
28
M2
29
M3
30
M4
12
XTIN
11
XTOUT
17
CFIN
18
CFOUT
33
DATA
31
POWER
21
S3
VOL
AM OSC
CT1-4
L4
AM OSC
L1
AM FERRITE-ROD
ANTENNA
ANT1
FM LEAD
ANTENNA
FM OSC
AM RF
IN
IN
L3
FM OSC
LCD1
LIQUID CRYSTAL DISPLAY
SEG13 – SEG23
COM1 – COM4
+4V
KEY MATRIX
SW3 – 13
1
1, 2
2
3
4
5
1
2
3
4
L2
FM RF
FM/AM FRONT-END,
FM/AM IF AMP, DET, AF AMP
IC1
SYSTEM CONTROLLER,
KEY CONTROL, LCD DRIVER
IC2
CV1-1 CT1-1
CT1-2
CV1-2
CT1-3
CV1-3
CV1-4
SW1
BAND
CV1
TUNING
D7, 8
(LCD BACK LIGHT)
RV1
VOL
+
+
FM
AM
• SIGNAL PATH
: FM
: AM
05
SW2
RANDOM
ID CODE
ALARM
3, 4, 5
PROGRAM
LIGHT CONTROL
48 – 58
K1 – K4
23 – 26
KS1 – KS3
32.768 kHz
2 MHz
X1
X2
HIGH FREQUENCY
TRANSFORMER
T2
36 – 38
62 – 59
HIGH FREQUENCY
TRANSFORMER
T101
POWER
TRANSFORMER
T102
DRY BATTERY
(IEC DESIGNATION 6F22)
“6F22” 1PC. 9V
B+
IC1 B+
+4V
PC1
AC IN
+4V
D1
T2
D4
D12
+
D13
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