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NI 5122/5124/5142 Calibration Procedure
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© National Instruments
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25
10. Measure the exact frequency of the peak around 11 MHz using the Extract Single Tone
Information VI with the following inputs.
•
advanced search»approx freq.
: -1
•
advanced search»search
: 5
•
export signals
: 0 (none)
11. Calculate the error in timing as parts per million (ppm) using the following formula:
error = (
a
- 11,000,000) / 11
where
a
is the measured frequency.
Compare the result to the
Calibration Test Limits
or the
Published Specifications
listed in
Table 11. If the result is within the selected test limit, the device has passed this portion of
the verification.
Note
The same time source is used for both channel 0 and channel 1, so you only
need to verify the timing accuracy on one channel.
LabVIEW VI
C/C++ Function Call
Call
niScope_Fetch
with
the following parameters:
timeout
:
5.0
vi
: The instrument handle from
niScope_init
channelList
:
"0"
numSamples
:
-1
LabVIEW VI
C/C++ Function Call
Perform an FFT on the array of
data from step 9.
Table 11.
NI 5122/5124/5142 Timing Accuracy Limits
Calibration Test Limits
Published Specifications
±5.3 ppm
±25 ppm