National Instruments NI 54 Series, Процедура калибровки

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Chapter 2 Verification
NI 54XX Calibration Procedure 2-10 ni.com
• Waveform —
NIFGEN_VAL_WFM_SINE
• Start_Phase —
0
5. Call
niFgen_InitiateGeneration()
to initiate signal generation.
This function causes the function generator to leave its configuration
state and enter its signal generation state. The only parameter required
for this function is
sessionHandle
.
6. Choose the input attenuator setting of the spectrum analyzer such that
the input mixer distortion does not limit the measurements.
7. Verify that there are no harmonics or spurs higher than –35 dBc in
comparison to the 1 MHz sine wave carrier.
8. Call
niFgen_Close()
to close the instrument I/O session, destroy the
instrument driver session and all of its properties, and release any
memory resources the driver uses. The only parameter required for this
function is the
sessionHandle
.
You have completed verifying the THD and the SFDR of your device.
Verifying Device Oscillator Frequency Accuracy
Use a counter/timer to measure the frequency accuracy of your NI 54 XX
device. The counter/timer should provide frequency measurement
accuracy of 15 parts per million (ppm) or better. The measurement
accuracy of your counter/timer depends on the accuracy of its timebase
and the measurement method you use.
Generate a 1 MHz frequency using your NI 54 XX device by completing the
following steps:
1. Complete the setup steps described in the Initializing Device for
Verification section.
2. Call
niFgen_EnableAnalogFilter()
to select the channel to
enable an analog filter on. Set the following parameters:
• vi —The output value
sessionHandle
that you obtained from
the
niFgen_init
function
• Channel_Name —
”0”
• Filter Correction Frequency —
1000000