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continuation of "sine on random..." from 23 Apr 09

continuation of "sine on random..." from 23 Apr 09

continuation of "sine on random..." from 23 Apr 09

(OP)
vibrationnewbie and IRstuff both make valid points -- yes, there is a fundamental difference between sinusoidal and random vibration.  However, you can still add the sinusoids to the random vibration in a time series and do a spectral analysis, getting both on the same graph.  I've done this in Matlab -- the random component is easy to simulate using a method from R. Mitchell (IFFTs, overlap, etc) and I have no trouble getting the spectral levels for the random component.  My question is for the sinusoids!  MIL-STD-810-G specifies them in g^2/Hz. Figure 519.6C-1 places a 40 Hz sinusoid on the chart with a level of 22.5 dB re 1g^2/Hz.  What amplitude sinusoid is this?  I can fudge in a number and try it to see where it comes out on the PSD graph, but I'd like to know how MIL-STD-810-G wants us to calculate it!

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