Re: x-ray with small Tesla coil as driver

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

Original poster: "Ed Phillips" <evp-at-pacbell-dot-net> 

Tesla list wrote:
 >
 > Original poster: "Jack Vandam" <snotoir7674g-at-mindspring-dot-com>
 >
 >  > Original poster: "Ed Phillips" <evp-at-pacbell-dot-net>
 >  >
 >   >........A note on the subject of small X-ray tubes.  I have one with a 2"
 > bulb
 >  > which was made by a friend of mine.....  By carefully playing around with
 > the pressure I can get it to
 >  > produce a reasonable X-ray flux operating from a 1" spark coil, but when
 >  > I hooked it to a small TC it almost melted into a puddle!
 >  >
 >  > Ed
 >
 > Hi Ed,
 >
 > I'm curious, what almost melted into a puddle- your tube or the TC?  I never
 > had this problem when I did my x-ray experiments several years ago.  I used
 > a 5" spark Tesla coil to drive the incandescents for up to 5 min.  The bulb
 > would get a little warm, but that was all.
 >
 > Jack

	The anode got so hot I was afraid it would melt (there was a bit of
exaggeration in what I wrote).  In this tube the anode is a 1/2" disk of
thin copper (no more than 0.032") and got red hot even when I was
running it from the spark coil.  Perhaps the focussing was better with
this tube so all the power was dissipated in the anode.

	The coil I used worked fine with my big and now defunct tube.  3" x 14"
secondary close wound with #30 wire and about 500 watts input from a 12
kV, 60 ma NST.  With a decent toroidal top terminal it puts out around
27" streamers, about the maximum I can have in the location I was
running it.

Ed