Tuner Section - Sony CFD-S39 Service Manual

TUNER SECTION

0 dB = 1 µV
• FM Section
Setting:
RADIO (BAND) button: FM
FM RF signal
generator
75 kHz frequency
deviation by 1 kHz signal
output level : as low as possible
• AM Section
Setting:
RADIO (BAND) button: AM
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
• Connecting Level Meter (FM and AM)
set
2 jack (J301)
• Connecting Digital Voltmeter (FM and AM)
100 k Ω
TP (VT)
(JW17)
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
TP (FM ANT)
0.01 µ F
set
Put the lead-wire
antenna close to
the set.
level meter
(range: 0.5–5 V ac)
32 Ω
digital
voltmeter
FM FREQUENCY COVERAGE
Frequency Display
Reading on Digital voltmeter
Adjustment Part
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L1
87.5 MHz
AM FREQUENCY COVERAGE
Frequency Display
Reading on Digital voltmeter
Adjustment Part
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L4
620 kHz
• For AM adjustment, fix the ferrite-rod antenna (L3) as shown
below and then perform tracking adjustment at L4 and CT3.
Lastly check the voltage.
Adjustment Location: See page 15.
– 14 –
ADJUSTMENT
87.5 MHz
1.6 ± 0.4 V
<confirmation>
CT1
108 MHz
CHECK
530 kHz
+ 0.7 V
1.0
– 0.5 V
<confirmation> <confirmation>
CT3
1,400 kHz
3.0 ± 1.0 mm
L3
AM
FERRITE-ROD
ANTENNA
108 MHz
4.3 ± 0.1V
L2
1,710 kHz
+ 1.2V
4.8
– 0.6 V