ACCEPTANCE TESTING
6-24
Spectral purity
Specification
For analog modulation and CW modes:
Harmonically related signals
for RF levels up to +7 dBm:
Less than -30 dBc for carrier frequencies up to 1 GHz.
Less than -27 dBc for carrier frequencies up to 2.7 GHz (2051T and
2052T).
Less than -27 dBc for carrier frequencies up to 5.4 GHz (2052T only).
Sub-harmonics:
Less than -90 dBc for carrier frequencies up to 1.35 GHz.
Less than -40 dBc for carrier frequencies up to 2.3 GHz (2051T and
2052T).
Less than -30 dBc for carrier frequencies up to 2.7 GHz (2051T and
2052T).
Less than -30 dBc for carrier frequencies up to 5.4 GHz (2052T only).
Non-harmonics:
Less than -70 dBc for carrier frequencies up to 2.7 GHz at offsets of
3 kHz or greater.
Less than -64 dBc for carrier frequencies up to 5.4 GHz (2052T only).
Residual FM:
Less than 7 Hz RMS in a 0.3 to 3.4 kHz unweighted bandwidth at a
470 MHz carrier.
Test equipment
Description Minimum
specification Example
Modulation meter
Capable of measuring residual FM less than 7 Hz
Aeroflex 2305
Spectrum analyzer
10 kHz to 16.2 GHz frequency coverage
Aeroflex 2386
Residual FM
Test procedures
C0334
UUT
RF
OUTPUT
INPUT
Modulation Meter
RF
INPUT
2386/2380
Spectrum Analyzer and Display
(rear panel)
47.4 MHz
O/P
➤
➤
Fig. 6-12 Residual FM test set-up
(1) Connect the test equipment as shown in Fig. 6-12.
(2) Set the UUT to
[Carrier Freq.]
470 MHz
[RF Level]
0 dBm, modulation OFF.
(3) Set the spectrum analyzer to 470 MHz zero span.
(4) Measure the residual FM on the modulation meter in a 300 Hz to 3.4 kHz bandwidth, which
must be less than 7 Hz.