Sony WM-FX673, Руководство по обслуживанию

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AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
T2 450 kHz
AM VCO VOLTAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
T1 531 kHz 1.5 ± 0.1 V
Confirmation 1602 kHz 8.5 ± 1 V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L5 621 kHz
FM VCO VOLTAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
L2 87.5 MHz 3.4 ± 0.1 V
Confirmation 108 MHz Less than 10 V
TUNER SECTION 0 dB=1
µ
V
[AM]
Setting:
function
: RADIO
BAND button : AM
[FM]
Setting:
function
: RADIO
BAND button : FM
• Repeat the procedures in each adjustment several times, and the
tracking adjustments should be finally done by the trimmer ca-
pacitors.
FM VCO Adjustment
Setting:
Procedure:
1. Connect the frequency counter to pin
!™
of IC2 as shown the
figure below.
2. Tune the set to 98 MHz.
3. Adjust RV1 for 19 kHz reading on the frequency counter.
Specification: 18.95 kHz to 19.05 kHz
Adjustment Location:
0.001
µ
F
FM RF SSG
Carrier frequency : 98 MHz
Modulation
: no modulation
Output level : 0.1 V (100 dB)
TP (FM IN)
+
–
digital voltmeter
MAIN board
TP2 (VT)
+
–
IC2 pin
!™
+
1
µ
F
frequency counter
33 k
Ω
– MAIN Board (Side B) –
TP1
(FM IN)
IC2
1
12
T2 AM IF Adjustment
T1 AM VCO Voltage
Adjustment
L2 FM VCO Voltage Adjustment
RV1 FM VCO Adjustment
RV601 Tape Speed Adjustment
L5 AM Tracking Adjustment
TP2
(VT)
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
+
–
level meter
set
32
Ω
2
REMOTE jack (J701)
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level: as low as possible
+
–
level meter
2
REMOTE jack (J701)
set
32
Ω
0.01
µ
F
TP1 (FM IN)