Original poster: "Jolyon Vater Cox by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk> Sorry there was an error in calculation for mean number of cycles to peak voltage. The figure should be 18.27 cycles not 36.54 cycles as latter figure is number of cycles per beat, which is twice the former. Apologies for any confusion, Jolyon