On Wednesday 02 May 2012 17:12:56 Jon Elson wrote: > The spectrum is so full of noise all the way up and beyond the range > of the chart, that it has to be measured on some kind of machine. > > Jon >
I found the source of this pictures: http://www.mmrc.iss.ac.cn/~xgao/papernc/jounce20111122.pdf And I am not sure what was measured. From this motion profile (0.1 to 0.2 s time to reach max. velocity) I do not expect frequency components in the 800 to 1200 Hz range. Another point is that the spectrum does not look alike sinc. But I may be totally wrong. My experience using a MMA7260 http://www.freescale.com/files/sensors/doc/data_sheet/MMA7260QT.pdf is that you have some spectral components without a move. Switching off the drives makes sometimes a remarkable difference. Conclusion: not all vibrations are movement induced. Joachim ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
