Triggered Gap Safety

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Zimtesla-at-aol-dot-com>

I tried a triggered gap using the info provided on the website. While it
produced a spark to bridge the wide main gap and made a lot of nosie, I had
trouble finding the correct phasing. Looking at the triac output on a scope it
seems the coincidence with line peak was within a tenth of the control rotation
making it hard to adjust. 

Before I could work this out, a minor electrical catastrophy occurred. The
triggered gap was feeding high voltage from the ignition coil into the ground
of my NST and back through the controller to the house mains. Eventually a
short between the receptical ground and house hot lead occurred with a bright
arc and tripping of the circuit breaker. 

Just wondering if others had experienced feeding high voltage back through
ground and to warn that this is something not to be ignored. 
Jim