FM IF/RF ADJUSTMENT
10.7 MHz
Oscilloscope
FM mono
SIGNAL
GENERATOR
400 Hz,
FM modulated.
TEST
STAGE
AD-
JUST-
REMARKS
1. Using a
driver, turn
the core of
counter-
clockwise
before taking
it out of the
bobbin.
2. Adjust for
“IF”
curve.
Adjust for best
“S” curve.
Figure 7-l FM IF
1
IF
MHz High
frequency
Figure 7-2 IF CURVE
Figure 7-3 FM CURVE
Detection
Electronic
Repeat steps 1 and 2 until no further improvement can
FM
External
Voltmeter
Rod Antenna
Generator
Speaker
Terminal
Unit
be made.
Band
frequency
coverage
109 MHz
Highest
TC2
maximal output.
frequency
Repeat steps 4 and 5 until no further improvement can
be made.
88
Adjust for
maximal
108 MHz
108 MHz
output.
Repeat steps 7 and 8 until no further improvement can
be made.
5
Dummy
(See Figure
6
7
Figure 74 FM RF
Electronic
FM
Generator
Rod Antenna
9
VCO FREQUENCY ADJUSTMENT
Dummy
Figure
SIGNAL
400 Hz, 30%. FM modulated
GENERATOR
signal)
Figure 7-5 VCO FREQUENCY
To Telescopic Rod Antenna
FM mono position
98 MHz at
98 MHz
60
FM stereo position
Adjust for
38.00
100 Hz.
To Chassis
500hms
Output impedance of signal generator
Figure 7-6 FM DUMMY
