FM IF/RF ADJUSTMENT
SWITCH POSITION
SIGNAL
GENERATOR
STEf
,
TEST
STAGE
I
FRE-
QUENCY
1
2
3
F
4
5
6
7
8
10.7 MHz
T2
counter-
clockwise
IF
Tl
before taking
it out of the
bobbin.
2. Adjust for
best
“IF”
High
CUNB.
frequency
Detection
T2
Adjust for best
“S” curve.
fepeat
steps
1
and 2 until no further improvement can be made,
87.1 MHz Lowest
13
Band
frequency
coverage
109 MHz Highest
TC2
frequency
Adjust for maximal
output.
88 MHz
88MHz
L2
Tracking
108 MHz
108 MHz
TCl
Repeat steps 4, 5 and 6, 7 until no further improvement can
be made.
FM mono
1
400 Hz, 30%. FM modulated
DIAL
POINTER
A,$;y-
REMARKS
SETTING
I
I
I.
Using a minus
driver, turn
the core of
VCO FREQUENCY ADJUSTMENT
SIGNAL GENERATOR
400
Hz. 30%. FM modulated
I
(mono signal)
DIAL
FREQUENCY
POINTER
ADJUST-
REMARKS
SETTING
MENT
FM mono position
FM stereo position
(unmodulated)
98 MHz at 54
dB
98 MHz
VRI
Adjust for 38.00 kHz
f
1OOH.z.
Sweep
(TP2) (TP5)
Figure 7-l FM IF
later
si
c-:---a
(See
Figure 7-4)
generator
(TP2)
Figure 7-2 FM
RF
“inns1
(See Figure 7-4)
(TP4)
Figure 7-3 VCO FREQUENCY
Rl
=
37.5 ohms
..v
-
I
”
I
r
I
L
=
‘3
onms-==CR2 =
75
ohms
To chassis
Rl
=
500hms
ground (TP2)
2
=
50
ohms<R2
=
5.
ohms
2
:
Output impedance of signal generator
Figure 7-4 FM DUMMY
AC
POWER
SUPPLY
CORD
QACCZ0059AFOO
QACCL00155AFOO
QACCZ0060AFOO
7
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CYI
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