NI PXI-5600 Calibration Procedure 10 ni.com
8. Set channel A on the power meter to read 15 MHz.
9. Set channel B on the power meter to read 100 MHz.
10. Set the amplitude of the signal generator to offset the loss of the power
splitter so that you obtain 0 dB input to the NI PXI-5600.
Note If the power splitter you are using does not have a 6 dB loss, set the amplitude of the
signal generator accordingly.
11. Wait 200 ms for channels A and B on the power meter to settle.
12. Loop 21 times. Include the following steps in each loop:
a. Call
niTuner_CalGetStepFrequency with the following
parameters:
• startFrequency =
98 MHz (in terms of Hz)
• stopFrequency =
102 MHz (in terms of Hz)
• numberOf Steps =
21
• index = current index of the loop (first iteration is 0)
The return value is the frequency of the current loop iteration.
b. Set the signal generator frequency to the frequency value returned
(in Hz) by
niTuner_CalGetStepFrequency in step 12a.
c. Wait 50 ms for the signal generator to settle.
d. Acquire channels A and B on the power meter. Send them as
inputs to
niTuner_CalAdjustExternalCalibration with
the following parameters:
• IFOutputPower = channel A power (in dBm)
• RFInputPower = channel B power (in dBm)
• calibrationProcedure =
0 (temperature correction
coefficient)
13. Repeat step 12 until the done value returned by
niTuner_CalAdjustExternalCalibration on the last iteration
is
1 (or TRUE).
14. Call
niTuner_CalGetCurrentTemperature to determine the new
temperature correction coefficient (TempCo
new
).
15. Compare TempCo
new
with TempCo
old
to determine whether the
NI PXI-5600 meets its specifications. Refer to Table 2 for the
acceptable limits.
16. Call
niTuner_CalCloseExternalCalibration to end the
calibration session. Set action to
1 to cancel; do not save the result.
