ICF-C273
9
SECTION 3
ELECTRICAL ADJUSTMENTS
BAND button : AM
Volume : MIN
3-1.TUNER SECTION
AM Section
FM Section
BAND button : FM
Volume : MIN
Put the lead-wire
antenna close to
the set.
AM RF signal
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
W2
FM
wire
antenna
FM RF signal
generator
22.5kHz frequency deviation by
400Hz signal.
Output level : as low as possible
0.01 uF
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T1
450kHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust part
Frequency display
L4
531kHz
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 1
585kHz
CT1
1,485kHz
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.
L2
87.5MHz
CT3
108MHz
32
Ω
level meter
set
J251 (phones)
+
–
0dB=1
µ
V
L2 : FM tracking
adjustment
L1 : AM Tracking
adjustment
CT1 : AM tracking
adjustment
L4 : AM Frequency
coverage
adjustment
CT3 : FM tracking
adjustment
T1 : AM IF
adjustment
MAIN BOARD (SIDE A)
JW3 (VT)
digital voltmeter
(DC range)
