Using NI 9215 as a scope

[glskinner84]

Resistors would depend on my impendance of the system. Wouldn't a transformer not care about this?

[Dennis_Knutson]

Why would you assume the input frequency of your signal is 60Hz? You should know this from measuring it with the scope.

You can adjust the sampling rate and the number of samples. Have you looked at any of the examples that come with LabVIEW or have been posted here for using aDAQ card like a scope?

[glskinner84]

My frequency is varying from test to test....usually 10hz to 100hz. I have looked through example codes and the forums and can't find anything relate to a change in timebase. I know how to change the rate of sampling and number of samples....but I'm looking to manipulate the timebase to show a certain number of secs/div on the graph itself.

[Dennis_Knutson · Accepted solution]

It's basic arithmetic. Say you set the sample rate to 1000 samples per second. If you request 100 samples, you acquire them in 100 msec. If you request 500 samples, that takes 500 msec. Do you see how that affects sec/div on the graph?

[glskinner84]

Oh, I see. I wasn't looking at the "read" number of samples. I was looking at the "clocks". Thanks Dennis!