maintenance
PERFORMANCE TESTS
1, Set
the
Spectrum Analyzer
controls for the
appropriate
reference level, center
frequency,
span, and
resolution to display the
UUT signals and spurs
frequencies with
appropriate
noise floor and signal
resolution
for the following
steps.
1 . Verify the
spurs at
the offsets of 20 kHz,
30
kHz,
35 kHz, and
40
kHz are
<
-60
dBc.
2.
Verify
the spurs at the offsets of 1 MHz
and 10 MHz are <
-60
dBc.
3. Program the UUT level to 1 dBm
with
the EXT AM on at
30%
modulation
(no external
modulation
input is applied).
4. Verify the spurs at 10 MHz,
20
MHz,
and 30 MHz are <
-60
dBc.
5. Verify the spurs at
800
MHz,
and 1044.99 MHz are <
-60
dBc.
6. Program the UUT to 600 MHz, 0 dBm, EXT AM modulation off.
7. Verify the
spur
at 300 MHz
is <
-60
dBc.
4A-12. MODULATION TESTS
These tests use the Modulation Analyzer
to verify modulation accuracy and residual and
incidental modulation of
the UUT. The modulation
distortion is
verified by measuring
the demodulated output of the Modulation
Analyzer
with a Distortion Analyzer. The
internal modulation oscillator
frequency
is measured using the Frequency
Counter
on
the
demodulated output of the Modulation Analyzer.
Table
4A-2 lists the requirements for
the modulation tests.
REMARKS
Failing
this performance test
indicates
the need for repair
and/or recalibration
of the
associated circuitry.
Where residual noise affects the Modulation Analyzer
measurements accuracy, apply
correction methods provided by the Modulation
Analyzer manufacturer.
Table
4A-2.
Modulation
Tests Requirements
REQUIREMENTS
PARAMETER
SPECIFICATION
HOP FRER <iZX at 0.4 or 1 kHz
for
20 to 505'='C; add
l0.ix/5®c outside
this range.
AM ACCURACY
of setting) for internal,
rates
end depths of
99X or Less, and peak
amplitudes
of
+13
dSn or less.
AM
DISTORTION <1.5%
THD up to 3GK AM,
to 70X, <5X to 90X, at internal
rates. <3% to
70X AN, to 90X AM frequency
>
950 MHz,
level > dbn.
RESIPUAL AM <0.tX nas <-£0
dec) in a O.OS-kKz to 15~kMz bandwidth.
INCIDENTAL FM <0.3 fii
for
internal rates and <3Ctt AM,
FN ACCURACY
<17X for rates of 0.3 kHz
to
20 kHz. and
>100
Hz deviation.
FN DISTORTION <11
THD for rates of 0.3 kHz
to
20 kHz, and
>100
Hz deviation.
RESIDUAL
FM ms In a 0.3~kHz to 3-kKz band:
<10 Hz for 245 MHz to
S12
MHt
and
<20
Hz elsewhere.
ms in a D.OS-kHz to 15-kHz band:
<22 Hz for 24S MHz to S12 MH*
and
<40
Hz elsewhere.
INCIDENTAL AH
<1X AH at 1“kHz rate and for deviation <50 kHz.
I
E
E
4A-12
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