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FM VCO VOLTAGE ADJUSTMENT
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
L4
87.5 MHz
3 V ± 0.1V
Confirmation
108 MHz
Less than 11.8 V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L3
87.5 MHz
TC3
108 MHz
AM (MW) VCO VOLTAGE ADJUSTMENT
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
L5
530 kHz (531kHz *1)
2.65 V ± 0.1V
Confirmation
1,710 kHz
Less than 10 V (9.5 V *1)
(1,602 kHz *1)
AM (MW) TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L1 (L1-1 *2)
580 kHz (621 kHz *1)
TC1
1,490 kHz (1,404 kHz *1)
LW VCO VOLTAGE ADJUSTMENT
*
2
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
TC4
153 kHz
2.25 V ± 0.05V
Confirmation
279 kHz
Less than 9.5 V
LW TRACKING ADJUSTMENT
*
2
Adjust for a maximum reading on level meter.
L1-2
162 kHz
TC2
243 kHz
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T1
450 kHz
*1) Except US, Canadian models
*2) ICF-C793L
*2) ICF-C793L
SECTION 4
ELECTRICAL ADJUSTMENTS
0 dB = 1 µV
[FM]
Setting:
Band switch: FM
Band switch: FM
[AM (MW/LW)
*
]
* AM
: ICF-C793
MW/LW : ICF-C793L
Setting:
Band switch: AM (MW/LW)
Band switch: AM (MW/LW)
• 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.
• Remove FM antenna in FM adjustments.
Adjustment Location: Main Board (See page 8)
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level: as low as possible
deviation by 400 Hz
signal
Output level: as low as possible
+
–
–
level meter
MAIN board TP (SP GND)
MAIN board
TP (SP +)
TP (SP +)
set
TP (FM-IN)
8
Ω
0.01
µ
F
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
Output level: as low as possible
modulation by
400 Hz signal
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
antenna close to
the set.
+
–
–
level meter
set
8
Ω
MAIN board TP (SP GND)
MAIN board
TP (SP +)
TP (SP +)
+
–
–
digital voltmeter
MAIN board
TP (VT)
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