Thorated vs Pure Tungsten

Hi All,

	I use 1/8 inch diameter thorated tungsten rods in my new neon protection
circuit as safety gaps.  However, they tend to sporadically fire at low
voltages.  The ends are cut pretty square instead of being rounded.  I can
replace the rods with the pure tungsten ones and grind them round on the
ends.  However, I was just wondering if the thorium was mostly to blame for
the sporadic firing or the square ends?  This happens with nothing else
connected except the neon running at full normal voltage.

	I really think, now, that the pure tungsten is by far the best for Tesla
coil applications.  The slight radioactivity of the thorated versions is
unsettling and this sporadic firing thing is a pest.  The tungsten rods
seem to be far far better than anything else I have used and are definitely
the way to go for gap electrodes, as so many have found...