Low Amplitude Signal on PXI-4461

[MrHappyAsthma]

I am curently using two PXI's to output an analog signal through LabVIEW 2009 to an oscilloscope:



PXI-4461 is running the attachment (labeled appropriately) below.  It also produces the green line on the graph.  It appears correct on the oscilloscope.

PXI-5412 is running the other attachment (labeled appropriately) below.  It produces the yellow line on the graph.  This amplitude is measured correctly (or so it shows in the margin of the picture), however it gives me a "Low Signal Amplitude" warning and displays the wave much smaller than the "correct" version from the 4461. 

*Note:  I suppose it is possible that the PXI-4461 (green) is wrong and the PXI-5412 (yellow) is right, but since the PXI-5412 (yellow) produces the error, i am lead to believe that it is the problem.

I could use some help figuring out what might be causing this inconsistency and how might I go about remedying this issue.

[OlivierL · Accepted solution]

This has nothing to do with LabVIEW.  It is all oscilloscope related.  The reason the yellow signal is smaller than the green is because your scales are different.  Look at the bottom of your oscilloscpe: Ch2 says "500mV per division" while channel 3 says "1V per division".  You probably get a "low signal amplitude" because you signal is less than "2 divisions" and the scope sugests you to change this.  There should be a button named "Autoscale" on your scope which you can hit if you want. 

[MrHappyAsthma]

Ah I can't believe it was something so simple.  I was dreadfully confused.  Thank you so much!