Original poster: "Barton B. Anderson by way of Terry Fritz <teslalist@qwest.net>" <classictesla@netzero.com> Hi All, Jon has updated his schematic of his design for the zero-crossing trigger gap circuit. I replaced the old schematic at my site with the new one. Here's the link: http://www.classictesla.com/download/stsg_zc_driver.gif Take care, Bart