26
|
ni.com
|
NI 5114 Calibration Procedure
9.
Retrieve a waveform using the niScope Fetch (poly) VI. Select the Array Measurement 1D
DBL instance of the VI. Use the default value for the
timestamp Type
parameter.
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
Published Specifications
column listed in Table 8. 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
Measurement
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.
