Peter Feucht >For example, if the fundamental (the heart rate) was close to 60Hz, the > result could be a very strange waveform. > > A heart rate of 60Hz? In that case you no longer need any ECG analysis...= .. > Important are details within the cycle. At 5Hz rate you won't get needed resolution with 60Hz filter. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .