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FM MPX Section
1.
Set FM signal generator at external modulation.
Connect generator
output to unit's FM
antenna
terminals
via 300-ohm
balanced
dummy
anten-
na. Set
FM
SG
output to
60dB.
2.
Adjust MPX
signal generator
to
obtain
main
signal modulation
of
1kHz, 67.lkHz
frequency
deviation. Connect
to
FM
SG's
external modu-
lator
terminals.
Gl)(-747
A
Connect the
oscilloscope
horizontal inputs to
MPX
SG's
PILOT OUT terminals and
Vertical
inputs
to No.18
terminal of tuner
assembly.
Tune
unit
and
FM
SG
to
98MHz.
Produce
a
Lissajous
pattern on
oscilloscope and
adjust VR1
to
make the
pattern still.
Then
set signal generator
for
modulation
of
L
(later
R)
and
pilot.
Adjust VR2
to
obtain
maximum channel separation.
3.
4.
5.
6.
FM signal generator
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MPX
signal
generator
27
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