LabView Signal Problem

[AlejandroVargasD]

I am using a PXI-6229 National Instruments device and the LabView Software. I only use two channels (A0 and A1) to acquire data at a frecuency of 1000Hz. The problem is that the signals contaminate each other; when obtaining da, one signal pulls the other. I already try different solutions (diodes, filters and other devices before the device input). I think the problem is within the device, which somehow crosses the signals.

Any suggestions?

[santo_13]

You may be experiencing ghosting which is expected in multiplexed ADC based DAQs. Please read the following articles,

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000P9mKSAS&l=en-US

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000YHy6CAG&l=en-US

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000P84RSAS&l=en-US

[Bob_Schor]

Are you recording "single-ended" or "differential"?  Are your wires shielded?  Know anyone with a little knowledge of electronics?  Can you define the signals you are recording?  You are sampling at 1 kHz, so I'm assuming that the signals are relatively low frequency (which means a top frequency of a few (like 2-3) hundred Hz -- is that correct?

Have you looked at the signal(s) with an oscilloscope?  What do you think the signals should be?  What are the amplitude(s) of the signals (tell us mean and rough peak-to-peak values)?  [Use an oscilloscope if possible].

Bob Schor