Reading data with NI-5772

[PatrickR]

I am trying to read data with the NI-5772.  I have tried the example code(NI 5772 - Getting Started (Host).vi) , and it will read noise (with nothing plugged in to either channel).   However when I attempt to route a signal in (such as one generated with a NI-DAQ board on the same system and routed to AI0/AI1), the signal doesn't change much from the noise.   I updated the drivers and am running LabView 2012 (both 32-bit and 64-bit, I get the same result)

Has anyone else experience this problem?   Thanks.

[PatrickR]

Ok,  apparently it just didn't like our input signal  ( a 1 khz sine wave generated from NI-MAX).  We tried a source with a higher output rate (several MHz) it seems to work OK.  Is there some sort of high pass filter on the input?

[Nathan-P · Accepted solution]

Yes, the device is AC coupled and has a high pass filter.  There is a frequency response graph on p.20 of the User's Manual:

http://www.ni.com/pdf/manuals/373625a.pdf

It appears that the cuttoff frequency is about 100kHz.