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PXIe-5665 Calibration Procedure
17. Depending on your equipment configuration, using the spectrum returned from the
PXIe-5665, measure the power at the center frequency and record this value as the
Small
Tone First Measurement
(RF source 1 output disabled) or as the
Small Tone Second
Measurement
(RF source 1 output enabled).
18. Repeat steps 8 to 17 for all test frequencies in step 8.
19.
(PXIe-5665 14 GHz VSA)
Repeat steps 8 to 18 for frequencies greater than 3.6 GHz with
the PXIe-5665 preselector enabled.
20. Repeat steps 7 to 18 with the PXIe-5665 preamplifier enabled for frequencies less than
3.6 GHz.
21. Enable the RF source 1 output.
22. Repeat steps 6 to 20 with the RF source 1 output enabled.
23. Calculate the PXIe-5665
Gain Compression
using the following equation:
Gain Compression = Small Tone First Measurement - Small Tone Second Measurement
24. Compare the
Gain Compression
to the verification test limits in Table 51 or Table 52.
Table 51.
Gain Compression Verification Test Limits (>700 MHz, Preamplifier Disabled)
Frequency
Limit
Compression
(dB)
Applied Power
(dBm)
>700 MHz to
1.70 GHz
As-Found
1
+8.0
As-Left
*
1
+9.1
>1.70 GHz to
3.6 GHz
As-Found
1
+6.0
As-Left
*
1
+7.1
*
section of this document for more information
about as-left limits.
The device specification calls for less than or equal to 1 dB gain compression for a minimum
applied power. The applied power includes the measurement uncertainty to guarantee the
required minimum applied power.