It is true that some vacuum tubes which are capable of anode voltages of 400 to 500 volts can produce x-ratys. The first X-ray tube was nothing more sophistocated than a high voltage diode which could be pumped to various levels of vaccum and operate at various applied high voltages. The device emitted x-rays even if the vacuum was poor, as long as the anode voltage was high enough to accelerate the litte e's fast enough to strike their but on the anode with the energy to produce the x-ray. So, in theory, the vacuum tube can do this x-ray thing. BUT! The circumstances of wavelength and control require specific anode materials and kinetics and kinematic circumstances which produce hard, medium, soft rays, etc. which are really are a complex function of the set of parameters. With an excitation high voltage applied to a vacuum tube, say a beam power pentode, for example, you may ge able to control the acceleration with the control grid and screen grid bias but you have no control over the elemental circumstances. I saw that someone said you were about to venture beyond the "backyard enterprise". There is a bit of truth here, perhaps some experience and no doubt some wisdom. BUT!!! I hope you will be neither discouraged nor disuaded from your venture "into science fiction". It is a wonderful journey. GOOD LUCK. Bon Voyage. ---------- > From: Jim Hutchison > To: PICLIST@MITVMA.MIT.EDU > Subject: Re: move to newsgroup > Date: Wednesday, May 06, 1998 7:43 PM > > >I'll add another no vote to moving the PIClist to the newsgroups. > >I have access to the newgroups, but rarely visit; the signal-to-noise is > >unacceptably poor. (I REALLY don't want to buy pictures of someones grand- > >mother doing weird things with one of our four-legged friends.) > > >I, for one, like the diversity of people and projects this list delivers > >just the way it is. It's nearly Spam-free! > > > >John > > Add my no vote. I Agree! > > Thanks > Jim Hutchison