Signal Filtering

[LarsUlrich]

Ok thanks for all your help.

Playing around with the settings, I have discovered that when the cutoff frequency is set to 399 Hz, it functions, but once I set it at 400+ I get the same error.

[Dennis_Knutson]

Do you think the error might have something to do with sampling at 800 Hz? Look at the error message.

[LarsUlrich]

Ahh, I see.  You are saying my fs is my 1/dt, thus with a dt at 0.00125, I can't filter out anything at 400 Hz or over.

Thanks for your all the help!

[johnsold]

Did you solve your problems?

The sampling rate/Nyquist criterion issue was the most significant.

Your data seems to have very little energy above about 200 Hz and filtering at 399 Hz has no effect visible at the level of a graph.

The signal coming out of the filter VI is just the amplitude information. It occupies only one column in the 2D array. No timing information is included. The (evil, as Dennis often says) Dynamic Data Type hides that from you. If you want to save timing information in the output file, you will need to put it back in.

Lynn