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CFS-W301
|
1-3.
RADIO
SECTION
ELECTRICAL
ADJUSTMENTS
FM SECTION
FUNCTION: RADIO
BAND: FM
FM rf signal
generator
400 Hz, 30% FM modulation
frequency deviation +22.5 kHz
Output level: as low as possible
FM antenna input
Za
:
0.01 uF
ke
322
!
FM TRACKING
ADJUSTMENT
Adjust for a maximum rading
on VTVM.
°
FM FREQUENCY
COVERAGE
ADJUSTMENT
Adjust for a maximum reading
on VIVM.
86.5 MHz
109.5 MHz
FM IF Alignment 2
Procedure:
FM rf signal
generator
Carrier frequency:
10.7 MHz
No modulation
Output level:
as low as possible
FM antenna input
PHONES
PHONES
[TUNER
BOARD]
oscilloscope
© Repeat the procedures in each adjustment several
times, and the frequency coverage and tracking
adjustments should be finally done by the trim-
mer capacitors.
VTVM
FM
IF ALIGNMENT 1
FM
antenna input
BAND
select switch
Turn T2 fully clockwise.
Make
sure
that sinewave
appears
three
times
when
changing
rf signal-generator
frequency
gradually.
Set
rf signal-generator
frequency
for
second
sinewave,
and
precisely
adjust
rf
signal-
generator
frequency
for maximum
reading on
oscilloscope.
_
Adjust T2 for maximum
reading and minimum
noise on oscilloscope.
°
rvi
\
}
VCO Adjustment
A)
Regular Method
Procedure:
FM rf signal
generator
Carrier frequency:
98 MHz
Modulation:
1 kHz, 30%
:
Output level:
562
wV (55 dB)
FM antenna input
9; 0
frequency counter
Oo
Oo
ome)
°
peren
|
|
fc kQ
ef
1C3
A
V
ome)
1.
Connect an electrolytic capacitor
(10 uF/16 V)
between pin (1) of IC3 and ground.
Unsolder the portion (A)
Tune the set to 98 MHz.
4.
Adjust
RV1
for
38 kHz
+0.1 kHz
on
the
counter.
5.
Remove electrolytic capacitor mounted
in step
1.
6.
Solder the portion (A)
wr
| CFS-W301
CFS-W301
|
AM
SECTION
FUNCTION : RADIO
BAND
:AM
©
AM rf signal
generator
Put the lead-wire
ae antenna close to
the set.
Cy
30% amplitude modulation
by 400 Hz signal
Output level: as low as possible
e@Repeat
the
procedures
in each
adjustment
several times, and the frequency coverage and
tracking adjustments should be finally done by
the trimmer capacitors.
on VTVM.
[TUNER
BOARD]
PHONES
AM
IF ALIGNMENT
Adjust for a maximum reading
on VTVM.
.
455 kHz
BAND select
switch
1,680 kHz
520 kHz
Adjust for a maximum reading
on VTVM.
AM
FREQUENCY
COVERAGE
ADJUSTMENT
— 10—-
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