8
WM-FS421
•
Switch Location
VOLUME
: MAX
MEGA BASS : OFF
AVLS
: NORMAL
BAND: AM
BAND : FM
TUNER SECTION
Put the lead-wire
antenna close to
the set.
30 % amplitude modulation by 400 Hz
signal.
Output level : as low as possible
AM RF signal
generator
0.01
µ
F
FM RF signal
generator
FM IN
point (TP2)
75 kHz(100 %) amplitude modulation
by 1kHz signal.
Output level: as low as possible
16
Ω
set
level meter
J301 (
i
)
Adjustment Location: Main board (See page 9)
0 dB = 1 µV
FM TRACKING ADJUSTMENT
Adjust for maximum reading on level meter.
L4
87.5 MHz
AM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a 1.1V
±
0.1Vde reading on digital voltmeter
L7
530 kHz
AM TRACKING ADJUSTMENT
Adjust for maximum reading on level meter.
L3
620 kHz
CT1
1,400 kHz
•
Repeat the procedures in each adjustment several times for the
maximum level meter indication.
•
The frequency coverage and tracking adjustments should be
finally done by the trimmer capacitors.
AM IF ADJUSTMENT
Adjust for a maximum reading on level meter
RV2
1,000 kHz
FM VCO Adjustment
Procedure:
1.
Connect the resistor 10k between TP1 and TP (VCO).
2.
Connect the frequency counter to TP1 (IC1 pin).
3.
Set FUNCTION switch to FM.
4.
Tune the set in 96MHz.
5.
Adjust RV1 so that the reading on the frequency counter
becomes 76 kHz.
Specifications: 75 kHz-77 kHz
TP2
TP1
0.01F
FM RF SSG
[MAIN BOARD] (SIDE B)
Carrier frequency
: 96MHz
Deviation
: none
Output level
: 562
µ
V(55dB)
TP2
(FM IN)
TP2
TP1
+
+
1
µ
F
[MAIN BOARD] (SIDE B)
frequency
counter
10k
Ω
TP1
TP
(VCO)
