Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Beans45601-at-aol-dot-com> i am building a TC and my primary starts off at 8". how big should the pipe i use for my secondary be? i was thinking 4-5". Also, how do you hookup the NST with the spark gap, ball at the top, secondary, primary, ect. Thanks