Note For Printed Wiring Boards And Schematic Diagram - Sony ICF-C490 Service Manual

4-2.

NOTE FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAM

Note on Printed Wiring Board:
• X : parts extracted from the component side.
• W : indicates side identified with part number.
• : internal component.
f
• : Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
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 / W or less unless otherwise
4
specified.
• : internal component.
f
• C : panel designation.
Note: The components identified by mark 0 or dotted line
with mark 0 are critical for safety.
Replace only with part number specified.
• A : B+ Line.
• H : adjustment for repair.
• Voltages are dc with respect to ground in no-signal
(detuned) conditions.
no mark : FM
( ) : AM
• Voltages are taken with a VOM (Input impedance 10 MΩ).
Voltage variations may be noted due to normal produc-
tion tolerances.
• Signal path.
F : FM
f : AM
• IC Block Diagrams
IC1 CXA1019S
30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
AM IF DET AGC
TUNING
METER
AF POWER AMP AM FE FM IF
FM
DISCRIMINATOR
FM FE
2 3 4 5 6 7 8 9 10 11 12 13
1
IC101 LM8562
28 27 26 25 24 23 22
T T T T T
T
GATE
THREE
INPUT
CIRCUIT
DISPLAY INPUT
CONTROL CONTROL
RESET
CONTROL
PWR UP
ALARM 1 CTR ALARM 2 CTR
COMP.
DISPLAY DECODER/DRIVER
1 2 3 4 5 6 7 8 9 10
9 9
14 15
21 20 19 18 17 16 15
T T
OSC
STAND INNER
BY DET OSC
OUTPUT
CTR
CONTROL
GATE
CONTROL
CONTROL
1/25 or 1/30
2Hz
SLEEP SNOOZE
CTR CTR
1/2
1Hz
RESET
SEC
CTR
TIME
SET
GATE
PF.
DET
TIME CTR
BLANK
FLASH
11 12 13 14
ICF-C490