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<DIV>Jim</DIV>
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<DIV>One of the downsides to retirement is lack of access to neat equipment for analyzing our toy airplanes. I don't recall the spectrum in the aforementioned measurements, except that high amplitudes were at pretty low freqs, so Jerry may be correct. </DIV>
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<DIV>After experiencing high servo current draw with an engine upgrade (4s) on a popular mount, I measured vibes with an accelerometer mounted to the aileron servo rails in a couple of different planes (geometric). Scary amounts of shaking going on there, installed one of Merle's mounts and things quieted down. I didn't see much need to continue measurements after the mount switch. I agree that there won't be much need with electrics either, but there may be insidious things pop up from the high rpm of the motor / gear train that will buzz something that we use.</DIV>
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<DIV>Earl</DIV></BODY></HTML>