5-2.
SCHEMATIC DIAGRAM
– 9 –
– 10 –
ICF-C121
• IC Block Diagram
IC1
CXA1019S
1
2
3
4
5
6
7
8
9
10
15
14
13
12
11
FM
DISCRIMINATOR
AF POWER AMP
AM FE
FM IF
TUNING
METER
AM IF DET AGC
FM FE
23
22
21
20
24
25
19
18 17 16
29 28 27 26
30
GND
GND
AF OUT
VCC
RIPPLE
FIL
TER
AF IN
DET OUT
AFC AGC
AFC AGC
IF GND
METER
N.C
FM IF IN
AM IF IN
FM/AM BAND
SELECT
FM/AM
IF OUT
FE GND
N.C
AM RF IN
FM RF
REG OUT
FM OSC
FM RF IN
AFC
AM OSC
VOL
NF
FM DISCRI
GND
GND
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
Ω
and
1
/
4
W or less unless otherwise
specified.
•
¢
: internal component.
•
C
: panel designation.
•
U
: B+ Line.
•
H
: adjustment for repair.
• Voltages are dc with respect to ground under no-signal
(detuned) conditions.
no mark : FM
(
) : AM
∗
: Impossible to measure
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
Voltage variations may be noted due to normal produc-
tion tolerances.
• Signal path.
F
: FM
f
: AM
Note:
The components identi-
fied by mark
!
or dotted
line with mark
!
are criti-
cal for safety.
Replace only with part
number specified.
Note:
Les composants identifiés par
une marque
!
sont critiques
pour la sécurité.
Ne les remplacer que par une
piéce por tant le numéro
spécifié.
