impulse on periodic signal from DAQ

[pcharles]

I'm using a myDAQ to measure a perioidic voltage signal, and I want to find the maximum and minimum of this signal. When acquiring the signal though, there seems to be a large impulse in the start of the acquisition data shown in one of the attachements. The capture is from a probe from before any filtering is applied to the signal. I'm not sure if this is an effect of the signal acquisition or something I am doing with the signal filtering, and I am new to signal processing in Labview in general.

In the picture, I acquire 2 signals at 1, split the signal at 2 (top signal is of interest), filter at 3, scale at 4, and display at 5.

Can anyone point me in the right direction of what could be going on in my code?

[fblerg]

You might want to test the signals that you acquiring in MAX. It seems like the signal is going from 0 to -4.5 V in a short time. You are using the DAQ Assistant, which could be the source of the odd signal. I would recommend running some of the DAQmx examples. These examples can be accessed by going to Help in LabVIEW –> Find Examples -> Hardware Input and Output -> DAQmx -> Analog Input.

Using Test Panels in Measurement & Automation Explorer for Devices Supported by NI-DAQmx

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000YGZPCA4&l=en-US