Duncan Carter wrote: > I write software for vibration data collection and the test case with a > narrow hardware filter followed by a wider dsp filter really looks like > the case that I often see where there are not ENOUGH of bits in the analog > data > driving the A/D converter. In our case, we use hardware from vendors > such as National Insturments. When NI first introduced their 24 bit USB > A/D converters, they seemed to think this would give adequate dynamic > range but eventually realized that additional hardware amplification was > needed. 24 bit A/D converter resolution may seem like a lot, it's not. We > still need adjustable gain and attenuation front ends. I don't know of any > way to look at the K3 A/D output in a way that would allow assessment of > this. If you could calculate a spectrum of the A/D > converter output, you could compare the peak and average spectrum output > to the noise floor of the spectrum. Back in the 12 and 16 bit A/D > converter days, we found that 12 to 14 bit A/D converter output was > necessary for good performance and our transducer signals levels > typically range from 5 to 20volts peak down to fractional microvolt > levels. You might look at the audio output but I'm not at all sure that > there wouln't be other issues that would spoil the measurement. > > Dunc, W5DC. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > >
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