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PXIe-5665 Calibration Procedure
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© National Instruments
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13. Commit the PXIe-5665 settings to hardware.
14. Enable the RF source 2 output and wait 250 ms, or wait 100 ms if the output is already
enabled. This wait time allows the PXIe-5665 and RF source 2 amplitudes to settle.
Note
Settling times are a characteristic of the RF source device. Refer to the
section of this document for a list of NI-recommended source devices and
device specifications. If you use an RF source device with different device
specifications, your settling times may differ from those listed in this procedure.
15. Read the power spectrum from the PXIe-5665.
16. 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).
17. Repeat steps 7 to 16 for all test frequencies in Table 42.
18. Repeat steps 7 to 17 with the PXIe-5665 preamplifier enabled.
19. Enable the RF source 1 output.
20. Repeat steps 6 to 18 with the RF source 1 output enabled.
21. Calculate the PXIe-5665
Gain Compression
using the following equation:
Gain Compression = Small Tone First Measurement - Small Tone Second Measurement
Table 44.
Gain Compression Test Settings (Preamplifier Enabled)
Setting
Frequency Range (MHz)
Limit
Value (dBm)
RF Source 1
Programmed Power
11 to 101
As-Found
-18
As-Left
*
-16
>101 to 701
As-Found
-15
As-Left
*
-13
RF Source 2
Programmed Power
10 to 700
Both
-54
PXIe-5665 Reference
Level
10 to 700
Both
-30
*
Refer to the
section of this document for more information
about as-left limits.