Original poster: "Mccauley, Daniel H by way of Terry Fritz <twftesla-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com> Just wondering what arc color tells about a coil output. On large coils the arcs seem white to bluish, yet my small coil runs purple. Are the arcs purple to begin with at low powers and just "seem" to get whiter/bluer as the power levels increase???? Thanks Dan