©
National Instruments Corporation
15
NI 5421/5441 Calibration Procedure
Verifying the Oscillator Frequency Accuracy
This test verifies the frequency accuracy of the oscillator on the
NI 5421/5441. The verification involves generating a 10 MHz sine wave
with the NI 5421/5441 and measuring the sine wave frequency with one of
the instruments from Table 2.
To verify the frequency accuracy of the oscillator on the NI 5421/5441,
complete the following steps:
1.
Connect the NI 5421/5441 CH 0 front panel connector to the
instrument measuring the frequency accuracy with a male BNC to
female SMB cable.
2.
Call
niFgen_init
(niFgen Initialize VI) using the following
parameters:
•
resourceName
: The name of the device that you want to verify.
You can find this name under Devices and Interfaces in MAX.
•
IDQuery
:
VI_TRUE
•
resetDevice
:
VI_TRUE
•
vi
: A pointer to a ViSession. The variable passed by reference
through this parameter receives the value that identifies the
session created by this function. This value acts as the session
handle and is passed as the first parameter to all subsequent
NI-FGEN functions.
3.
Call
niFgen_SetAttributeViReal64
to set the sample rate
(niFgen property node:
Arbitrary Waveform Output»Sample Rate
)
using the following parameters:
•
vi
: The session handle returned from
niFgen_init
•
channelName
:
"0"
•
attributeID
:
NIFGEN_ATTR_ARB_SAMPLE_RATE
•
value
:
100000000
4.
Call
niFgen_SetAttributeViReal64
to set the gain (niFgen
property node:
Arbitrary Waveform Output»Arbitrary Waveform
Gain
) using the following parameters:
•
vi
: The session handle returned from
niFgen_init
•
channelName
:
"0"
•
attributeID
:
NIFGEN_ATTR_ARB_GAIN
•
value
:
1
Note
You can adjust the gain value based on which measuring device you use.