You could be at a higher harmonic of the resonant frequency, here the amplitude of vibration may not be as great. Karl H. Cazzini (Ph.D) Research & Development Consultant 57 Auburn Street (ext.), Suite 3, Framingham MA 01701 U.S.A Tel (508) 620 8845 / (508) 875 2009 Fax (508) 620 8839 -----Original Message----- From: mems-mgr@ISI.EDU [mailto:mems-mgr@ISI.EDU]On Behalf Of c718806@showme.missouri.edu Sent: Saturday, February 13, 1999 9:41 PM To: MEMS@ISI.EDU Subject: Re: Multiple Resonance Frequencies Hello Lee, How do you know the resonance frequency? Depending on observation or your design value? In my experience, the resonant frequency is the one at which the amplitude is the biggest. So I think perhaps this lower frequency is not the resonant one which you think should be. Yahong On Thu, 11 Feb 1999, Chua Bee Lee wrote: > Dear All, > I have been working on folded beams resonators using square waves > to drive them. As I adjusted the driving frequency towards the resonance > value, I observed resonance at smaller amplitudes at lower frequencies > prior to the one that I was expecting. I would appreciate if someone can > provide some insight on that. > > Thank you. > CHUA Bee Lee > Department of Mechanical and Production Engineering > National University of Singapore > > >