In a message dated 00-02-22 20:22:45 EST, you write: << Original Poster: "Tom Stathes" <newphreak_16-at-yahoo-dot-com> > Does anybody know what is the aprox. max spark outmut > of a 1.2kw TC is. What voltage do you think this is? > Thanks --Tom >> Tom, If the coil is of optimal design, I use the formula: 1.7*sqrt input watts = spark length (inches) Figuring 1200 watts; sqrt of 1200 = 34.64, then multiply by 1.7 = 58.9" Cheers, John Freau