Original poster: Ed Phillips <evp-at-pacbell-dot-net> "I believe these handheld "tesla coils" may be those handheld neon tube testers which are commonly availble for about $100.00 each. Dan" Yep, they're leak detectors of a "kicker coil" configuration, something I don't usually consider a TC. I have one that's 88 years old and still works fine. Ed