Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Esondrmn-at-aol-dot-com> In a message dated 1/8/02 7:15:50 AM Pacific Standard Time, tesla-at-pupman-dot-com writes: > > When people say they have a 3" coil are they measuring the diameter of the > secondary or the toroid or what? Thanks. > > > Typically, this would be the diameter of the secondary . Ed Sonderman