NI-Scop Help

[VU-Wei]

Hi,

Anyone familiar with NI-Scope in Labview? We recently got a NI PCI-5153 digitizer. I met some problems:

1. I put a square wave signal from function generator into the digitizer. Using the SCOPE Soft Front Panel or the niScope EX Configured Acquisition.vi in the example package, I can read the square wave signal. But when I tried to use NI-SCOPE Express, I find the signal I read looks like the differntial form of the actual signal. I put the figures in the attachment. Anyone know where is the problem? Thank you!

[VU-Wei]

That's the simple block diagram I use for the NI-scope express.

Thank you.

[VU-Wei]

Eventually we want to use this digitizer for lifetime measurements. We have a external trigger signal from a chopper. We need to record about 500000 electric signal which exponentially decays close to zero in 5ms. Then we want to take 1000 average of these signals and get an exponential decays curve, fit it and find the decay time. Anyone have experiences or related VI using NI-SCOPE? Thank you!

[VU-Wei]

I tried to integral this signal using the integral x(t).vi. But what I got is no longer like a square signal. And I am afraid it will change the measurement results by doing integral if I want to measure the decay time from an exponential decay signal.  I think there must be something worng with the setting in the ni-scope express. But I just can not find it. Really appreciate your advices!

[Dennis_Knutson]

First, there is a dedicated board for NI Digitizers. Second, if you have a problem with some code, you need to attach the actual VI. There is absolutely nothing anyone can tell about how the Express VI is setup just by looking at an image. If you are going to attach a png, at least use a snippet (look it up in the help).