Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com> Hi, It still works pretty much the same. However, it is far safer to have the secondary grounded rather than connected to all the live primary circuit voltages. Cheers, Terry At 11:41 AM 5/16/2004, you wrote: >Would connecting the secondary to the primary cause any adverse effect's >in the performance of a coil?