rate of multiplexing

Hello

I use the Signal Express 3.0.  I used several data cables to connect the three channels. Sine wave signals with different sampling frequencies were sent to these channels. When I took a quick glance at her signas in the time domain and measuerd without delay, he showed that the rate of multiplexing are differrent. I wonder if it is possible to change the rate of multiplexing in Signal Express. Is this a problem for the acquisition of data and the accuracy of the data?

Thank you very much!

Ningyu,

It is normal to see a delay without different or multiplexing rates because it is derived from the frequency you are sampling at.  With a higher sampling frequency, you'll need a faster clock to convert so all your channels can be tasted before the next edge of clock sample does not happen.  The documents below discuss what is the convert clock and how does one determine the rate.

What the clock Convert (channel) rates determined in NOR-traditional DAQ OR DAQmx?

http://digital.NI.com/public.nsf/WebSearch/42484E84DA98053686256D32006E0494?OpenDocument

Difference between the sample clock (clock scan) and convert (channel clock)

http://digital.NI.com/public.nsf/allkb/4D1435DF82EF494186256D8A006DD6D4

Tags: NI Products

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