Performance Tests
Performance Test 3
3-75
Modulation Test (96270A, Optional)
Equipment required for this test:
• Spectrum Analyzer/Measuring Receiver
To verify the amplitude and frequency modulated outputs of the UUT:
Note
Verification of phase modulation is not required as phase modulation
is created as sinusoidal frequency modulation with peak deviation
derived from the phase deviation and rate settings.
1. Connect the UUT Microwave output to the RF INPUT of the Spectrum
Analyzer/Measuring Receiver.
2. On the Spectrum Analyzer/Measuring Receiver push PRESET and then
select Measuring Receiver Mode.
Note
It may be necessary to readjust the measuring receiver’s settings
from those automatically configured in the modulation measurement
mode. In particular, to ensure the demodulation bandwidth and
measurement time settings are adequate to accommodate the
modulated signal RF spectrum and to capture at least five cycles of
the modulation waveform.
3. On the UUT press the SIGNAL key, and select the Microwave output. On
the UUT press the MOD key, followed by the Modulation Select softkey
and ensure amplitude modulation (AM) is selected. Set the UUT as
follows:
Frequency 30 MHz
Level +10 dBm
Mod Rate 20 kHz (Sine)
AM Depth 50 %
Output OPER
Modulation ON
4. Use the Spectrum Analyzer/Measuring Receiver autotune feature to tune
to the input signal and measure the AM rate. Verify that the measured rate
is within the tolerance listed in Table 3-31.
5. Set the UUT modulation rate to 100 kHz and repeat step 4.
To Next Page
Loading...
