Sony CDX-3167, Руководство по обслуживанию

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SECTION 3
ELECTRICAL ADJUSTMENTS
TEST MODE
This set have the test mode function. In the test mode, FM Auto Scan/
Stop Level and AM Auto Scan/Stop Level adjustments can be
performed easier than it in ordinary procedure.
<Set the Test Mode>
1. Set the “OFF” mode.
2. Push the preset 4 button.
3. Push the preset 5 button.
4. Press the preset 1 button for more than two seconds.
5. Then the display indicates all lights, the test mode is set.
<Release the Test Mode>
1. Push the OFF button.
TUNER SECTION
Cautions during repair
When the tuner unit is defective, replace it by a new one because
its internal block is difficult to repair.
0 dB = 1 µV
FM VT Voltage Adjustment
Setting :
SOURCE button : FM
FM Center Adjustment
Setting :
SOURCE button : FM
Procedure :
Adjust for following value reading on digital voltmeter.
Frequency Display 87.5 MHz 107.9 MHz
Reading on Digital voltmeter 1.42 ± 0.05 V 7.2 ± 0.5 V
Adjustment Part T4 (confirmation)
Adjustment Location : See page 18.
digital
voltmeter
+
–
FM VT OUT
dummy
antenna
antenna
terminal
50 Ω
50 Ω
set
FM RF signal
generator
dummy
antenna
antenna
terminal
50 Ω
50 Ω
set
FM RF signal
generator
digital
voltmeter
+
–
IC2 pin
!¶
IC2 pin
!£
FM CENTER
OUT
(Both side
of R32.)
Procedure :
1. Adjust T5 on TU1 so that the reading on the digital voltmeter
becomes in 0 ± 50 mV.
2. Output an Fcenter 10 dB signal output from FM RF signal
generator so that the LINE OUT REAR jack is –20 dBs.
3. Change the FM RF signal generator frequency and check the
deviation of the frequency on + side and – side when the LINE
OUT REAR jack drops 3 dB. (Both + side and – side is approx.
50 kHz.)
4. Re-adjust T5 on TU1 when the difference deviation of the
frequency does more than 10 kHz.
0 dBs
–3 dBs
(fc–10)
(fc+10)
fc (kHz)
Adjustment Location : See page 18.
Carrier frequency : 98.1 MHz
Output level
: 60 dB (1 mV)
Mode : mono
Modulation : 1 kHz, 75 kHz deviation (100 %)