Original poster: "Chris Dobson by way of Terry Fritz <twftesla-at-uswest-dot-net>" <cdobson-at-microtech-dot-com.au> Dear List I am using Tesla coil CAD ( Thanks to Richard Chapman), but I note that it is based on a supply frequency of 50 Hz. As the mains supply is 50 Hz here in Australia, by how much would the output parameters be affected ? Can anyone say?? :^D Chris Riana, TAS