Acquiring a sine wave of 1KHz riding on a DC and Detecting its peak value through compact rio

Dear LabView Programmers,
We are trying to acquire a sine wave input through cRIO-9004 using I/O module cRIO-9215 which is a 16-bit ADC.
We are able to acquire sine wave below 100Hz faithfully but not higher frequencies, the higher frequencies(1Khz) get distorted. How to acquire this sine wave of 1Khz faithfully through the above mentioned hardware.
Regards
LabView Lovers

Using LabVIEW 8.0, you will need to place the data from the 9215 into a dmaFIFO buffer, such that you do not need to poll the 9215. It is the polled or the interrupt process that reduces the sample rate.
Hope this helps.
Preston Johnson
Principal Sales Engineer
Condition Monitoring Systems
Vibration Analyst III - www.vibinst.org, www.mobiusinstitute.com
National Instruments
[email protected]
www.ni.com/mcm
www.ni.com/soundandvibration
www.ni.com/biganalogdata
512-683-5444

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Attachments:
qcm.vi ‏98 KB

I might be confusing analog and digital. My english is very bad especially when it's technical, and yes I have absolutely no academic background in either subjects.
The signal coming in is in the form of a sine wave, and the sine wave is coming from 2 oscilators, which are oscillating at 9.2 megahertz and are powered by 9v batteries. One of the oscillator wires travels through a crystal which causes the frequency to shift. Then both of the wires go to a mixer, and the frequency coming out is the frequency difference between the sine waves. This frequency will always be between 200 hertz and 0. I have that connected to an rs232 which is connected to my computer.
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Message Edited by Jaime F on 02-06-2008 11:42 AM
Jaime Hoffiz
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NICS
Christian Loew, CLA
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Thank you

Mostly like the phase is being reported
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I took a look at your code and I am a
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Although many topics of simultaneous analog output and input can be found in NI Developer Zone, I have not found a case similar to my project. I'm trying to generate a 1kHz sine wave by using the analog output of NI DAQPad-6070E, and acquire one channel input signal simultaneously. I found most of the examples can not work properly above 100Hz. Any suggestions are welcome. Thank you.
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I have sucessfully solve the problem when I observed the increase of
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On Tue, 3 Feb 2004 09:03:07 -0600 (CST), jujian wrote:
>Although many topics of simultaneous analog output and input can be
>found in NI Developer Zone, I have not found a case similar to my
>project. I'm trying to generate a 1kHz sine wave by using the analog
>output of NI DAQPad-6070E, and acquire one channel input signal
>simultaneously. I found most of the examples can not work properly
>above 100Hz. Any suggestions are welcome. Thank you.
>
>Jian

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Message was edited by: Imol

Acquiring a sine wave of 1KHz riding on a DC and Detecting its peak value through compact rio

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