problem with butterworth filter

[fenny]

i want to use butterworth filter to filter my data. my objective is to filter out the low frequency part. so i set filter type as" high pass", and set "low cutoff frequency" to be "6000". my sampling rate is set to be the same as i used in my data aquisition. but the filtered data looks strange. i mean the low frequency part (<60000hz) is still there [even with high peaks.] Did I make anything wrong while using butterworth filter? I'm expecting to see very little value in the range of less than 60000hz after the filtering. but i could not.

[Jonnie_5]

Personally, I've never used a butterworth at this high a frequnecy, but it's always worked fine for me in the 1000-10000 Hz range. Perhaps you could post your example code &/or data? Also, what order/pole are you using?

As a beginning point, use Help->Find Examples and search for Butterworth. Compare your design to those used in the examples, such as PtByPt and Array Based Filters.

[fenny]

I solved my problem by selecting higher order and added a window before the filter. THANKS!