CF3
mark
– 5 –
– 6 –
ICF-18
SECTION 5
DIAGRAMS
5-1. SCHEMATIC DIAGRAM
5-2. PRINTED WIRING BOARDS
Mark Center frequency
red 10.70 MHz
blue 10.67 MHz
orange 10.73 MHz
black 10.64 MHz
white 10.76 MHz
HOW TO CHANGE THE CERAMIC FILTERS
This model is used two ceramic filters of CF2, CF3.
You must use same type of color marked ceramic filters in order to
meet same specifications.
Therefore, the ceramic filter must change two pieces together since
it's supply two pieces in one package as a spare parts.
• IC Block Diagram
IC1 CXA1019S
1
2 3
4
5 6 7 8 9 10 1514131211
FM
DISCRIMINATOR
AF POWER AMP AM FE FM IF
TUNING
METER
AM IF DET AGC
FM FE
23 22 21 202425 19 18 17 1629 28 27 2630
GND
GND
AF OUT
VCC
RIPPLE
FILTER
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
N.C
FE GND
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.
• : panel designation.
• : B+ Line.
• : adjustment for repair.
• Power voltage is dc 3 V and fed with regulated dc power
supply from battery terminal.
• Voltages are dc with respect to ground under no-signal
(detuned) conditions.
no mark : FM
( ) : AM
[ ] : FM/AM
• Voltages are taken with a VOM (Input impedance 10 MΩ).
Voltage variations may be noted due to normal production
tolerances.
• Signal path.
: FM
Note on Printed Wiring Board:
• : parts extracted from the component side.
• p : parts mounted on the conductor side.
• ¢ : internal component.
• : Pattern from the side which enables seeing.
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