USB-6211 noise problem

I use an NI USB-6211 device, Windows XP, and I have the problem of blood (photo attached).

My analog differential signal (signal DC to DC power supply) is connected to an analog input in box usb-6211 (AI1 and AI9 ports).

The signal I get is evolving between 0V the Volt of entry (in the attached photo - 4V) instead of 4 v DC.

It might be a good idea to test it with a 9V battery using a differential connection with wiring configuration described in the manual (photo and link below). I know it sounds Basic, but re-seats black connector of i/o to the device might help. Make sure you reference GND AI as well.

Tags: NI Hardware

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