X-Mozilla-Keys:                                                                                 

Perry Mick wrote:

I'm still getting bothersom vibration, rubber mounts would probably
knock out 90 percent of it.  I have hooked up my new Analog Devices
accelerometer, and the amount of harmonics is amazing (resonances).
I had to put a low-pass filter in just to make sense of it in relation
to prop rpm.

Jeff Spitzer wrote:

Actually what you need is a spectrum analyzer.  That will allow you to
dissect every part of the signal by frequency and determine which
frequencies are dominant.  It's really difficult to dissect it otherwise
because of the superposition of waves.  Your low pass filter will help take
out the stuff you're really not interested in but you'll still have trouble
with contributions of imputs with nearly similar frequencies.  Sorry I
forgot to mention this previously.

Jeff Spitzer

 
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