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QOT-27H{R)
©
FM IF/RF ADJUSTMENT
SWITCH
POSITION
400 Hz, 30%, FM modulated.
FRE-
AD-
QUENCY
|POINTER | JUST-
SETTING | MENT
T1
SIGNAL
GENERATOR
TEST
STEP | STAGE
1. Using a minus
driver, turn
the core of
T2 counter-
clockwise
before taking
it out of the
bobbin.
2. Adjust for
best "1F''
curve.
Adjust for best
"S" curve.
10.7 MHz|
High
frequency
Detection
eee
7
steps 1 and 2 until no further improvement can
eee
7
made.
87.3 MHz|
Lowest
L3
frequency
108.3
Highest
TC2
MHz
frequency
Repeat steps 4 and 5 until no further imporvement
can be made.
88 MHz
88 MHz
pie!
Repeat steps 7 and 8 until no further improvement can
be made.
Band
coverage
Adjust for
maximal
output.
Adjust for
maximal
output.
VCO FREQUENCY ADJUSTMENT
SIGNAL
GENERA.
TOR
400 Hz, 30%, FM modulated
(mono signal)
DIAL
AD-
FREQUENCY
POINTER
JUST-
SETTING
MENT
FM mono position
FM stereo position
(unmodulated}
98 MHz
VR1
Adjust for
10.7 MHz
FM Sweep
Generator
;
Oscilloscope
Telescopic
Rod Antenna
0.01 uF
Figure 12—1 FM IF
vv
10.7 MHz
|
10.7 MHz
Figure 12—2
IF CURVE
Figure 12—3
S CURVE
Electronic
FM Signal
Rod Antenna
IC3
Generator
Dummy
(See Figure 12—6)
Figure 12—4
FM RF
FM Signal
Generator
300 kohms
GND
Dummy
(See Figure 12—6)
Figure 12—5
VCO FREQUENCY
Rt
To Telescopic Rod Antenna
r
R2
1 &)
L
To Chassis GND
a
R1 = 37.5 ohms
27S Cn
S89
98 obs
Ri = 50 ohms
Z=50 ohms<
5 Bien aes
Z: Output Impedance Of Signal Generator
Figure 12-6
FM DUMMY
=47=
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