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b.
Depress lEFT, RIGHT button on DISPLAY
ECT switch (AlSl1).
Depress NARROW button on switch AlS4B.
c.
Adju
A4R99 until
volts above ground.
Hive peak of sawtooth wave is
3
d.
Adjust A4RI08 until negative
below ground.
k
of sawtooth is
3
volts
e.
Touch up either A4R99 or A4R108 until the
k to
voltage of the sawtooth wave is symetrical around ground.
f.
Attach a frequency counter to the junction of A4C88 and A4Z2.
Adjust A4l18 for 11.145 MHz.
g.
CARRI
FREQUENCY thumbwheel (AlS2) to the frequency
you will use with your FM
gna1 Generator for RF Calibra on.
h.
Connect 691 Monitor for Spectrum Anal
(Section
1 (9)).
display
i.
Connect
F~1
Signal Generator to ANT input (A1Jll).
Set
frequency of generator to that shown on the CARRI
FREQUENCY thumbwheel (A1S2).
Modul
the
Si
1
Generator
with a
KHz
at approximately
KHz
iation.
j.
Adjust A4R97 until
edge of the scope
120 KHz sideband appear near the
splay,
k.
Adjust A4C30 to
Spectrum Analyzer display.
1.
Depress WI
button'on
frequency to about
300
necessary) until 300
scope
splay.
switch AlS4B.
Increase modulating
KHz.
Adjust A4Rl14
A4RIIO
(if
sideband appear near the edge of
3.
DEMODULATOR ALIGNMENT
a.
Connect 691 Monitor for Spectrum Analyzer disp1ay
(
tion
1 (9)}.
b.
Connect FM Signal Generator to ANT input (A1Jl1).
frequency of generator to that shown on the CARRIER
FREQUENCY thumbwheel (AlS2).
c.
Modulate the signal genera
with an audio tone of
13586 Hz.
Increase the level of the tone until
carrier nulls for the s
me.
At this
int the
signal generator ;s deviating exactly
KHz (100%).
d.
Adjust A4R121 until MOD PEAK lamp lights at 100%.
e.
Reduce audio
frequency to 400 Hz.
Adjust level for
100% modulation.
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