Read Sony SRF-M73 Service Manual online
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AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
T1
450 kHz
AM VCO VOLTAGE ADJUSTMENT
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
L4
530 kHz (531 kHz)
3 ± 0.1V
Confirmation
1710 kHz (1602 kHz)
9 ± 1V (8.5 ± 1V)
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L1
580 kHz (621 kHz)
CT1
1,490 kHz (1,395 kHz)
FM VCO VOLTAGE CONFIRMATION
Frequency Display
Reading on Digital Voltmeter
87.5 MHz
3 ± 0.3V
108 MHz
Less than 11 ± 1V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L2
87.5 MHz
CT2
108 MHz
( ): Panama model
SECTION 4
ELECTRICAL ADJUSTMENTS
0 dB = 1 µV
[AM]
Setting:
Band switch: AM
Band switch: AM
[FM]
Setting:
Band switch: FM
Band switch: FM
• Repeat the procedures in each adjustment several times, and the
tracking adjustments should be finally done by the trimmer ca-
pacitors.
pacitors.
Adjustment Location: Main Board (See page 7)
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
2
jack (J1)
set
MAIN board
TP (FM IN)
TP (FM IN)
32
Ω
0.01
µ
F
+
–
–
digital voltmeter
MAIN board
TP (VT)
FM Free-Run Adjustment
Setting:
Procedure:
1. Connect the frequency counter to TP (MPX) as shown the fig-
1. Connect the frequency counter to TP (MPX) as shown the fig-
ure below.
2. Tune the set to 98 MHz.
3. Adjust RT1 for 76 kHz reading on the frequency counter.
3. Adjust RT1 for 76 kHz reading on the frequency counter.
Specification: 75.8 kHz to 76.2 kHz
Adjustment Location: MAIN board (See page 7)
0.01
µ
F
MAIN board
TP (FM IN)
TP (FM IN)
set
FM RF signal
generator
generator
Carrier frequency : 98 MHz
Modulation
Modulation
: no modultion
Output level
: 0.1 V (100 dB)
+
–
–
MAIN board
TP (MPX)
+
1
µ
F
frequency
counter
counter
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
32
Ω
2
jack (J1)
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