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I
R I
I
R 2
C
I
I
'
DUMMY
I
I
I
ANTENNA:
Fig. 5
4.
FM I F Alignment
Volume Control : Minimum
1) Connect the out clip of
T. V. sweep generator's IF/RF OUTPUT lead to the local oscillator terminal
of V. Cap. and also the other clip to the earth.
2)
Connect the scope terminal of T. V. sweep generator to H. input of oscilloscope, and also the ground
terminal to earth of the H. Input.
3)
I F Alignment
( a )
Give the output from emitter side of X8 to V. Input of oscilloscope.
( b ) Give the unmodulated 10.7MHz marker of S. S. G. to the set.
( c ) Align L105,106, 1 , 2 so that the maximum sensitivity and symmetrical wave mode will be obtained,
setting the 10.7MHz marker on the peak.
4)
Discriminator Alignment
( a ) Give the output from detector transformer to
V. INPUT of oscilloscope.
( b )
Give the 10.7MHz marker of 50-60
db output modulated to 3 0 ~ 6 0 % by AM from S.S.G. to set.
( c ) Align L4 so that the sign wave appearing on the flyback line of 'IS" curve will disappear.
( d )
Align L3 so that the response of the "SN curve will become maximum and symmetry.
5) Repeat that step 3), 4), and make sure that I F peak and center point of the "SN curve will exactly
coincide with 10.7MHz marker.
5.
F M R F Alignment
Volume Control
:
Maximum
Input Signal
:
Use 75Q terminal of S. S. G.
400Hz modulation, 22.5KHz deviation.
a
White lead wire which is connected to rod antenna.
- 5 -
Input
Frequency
1
It is given to
Places to be aligned
Position of V. Cap.
86.5MHz
2
I
109MHz
L103
1
Maximum Capacity
33
1
C103
I
Minimum Capacity
3
1
Repeat step 1 . 2
9OMHz
5
I
106MHz
6
1
Repeat step 4 , s
33
L101,102
1
9OMHz Signal
C104,105
1
106MHz Signal
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