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"Runaway breakdown" for creating *really* long sparks

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bill beaty

Fri Apr 06 2007, 12:03PM

Banned on April 8th, 2007.
Registered Member #597 Joined: Thu Mar 22 2007, 03:33AM
Location: Seattle, WA
Posts: 16

Bored Chemist wrote ...

I still stand my my assertion that "if electrons should travel across a voltage drop of approximately 1MV or larger, they suddenly are able to travel a hundred times further in air. " is wrong unless you add the rather important detail that having been taken up to a high speed they are not left to coast, but are pulled along by a further potential drop.

*ADD* that important detail?! But that important detail is what this thread is about! That's the thread title. That's why I thought that you didn't read the thread before commenting.

What is your opinion of Figure 2 in that article?

In this thread we're talking about the fields surrounding a large tesla coil having an odd effect on megavolt electrons. In other words, "suddenly are able to travel a hundred times further in air" is only odd if for some reason you take it out of the context of this discussion and for some reason pretend that we're *not* talking about adding a large ambient e-field.

Very oddly, steve C. made exaclty the same mistake with his earlier cyclotron photo: he offered that particular photo in order to disprove all the physics papers describing runaway breakdown. But that photo lacks the large e-field which is the main feature of runaway breakdown. Seems like quite a large error to me, one that I wouldn't expect he or you to make.

Anyway...

Probably it will be against DOE licensing laws for hobbyists to experiment with radioactive sources which provide plenty of +1MeV electrons. A hot filament, or better yet, a cold cathode, when paired with a high-vac drift tube and a Tesla coil, would provide an enormous supply of such electrons. Cold cathode style x-ray sources apparently don't even require much more than a rotary vacuum pump. And various articles suggest that it isn't too hard to get those electrons out into the air: if the beam current is high enough, the portion of "fast electrons" not stopped by a glass wall will be significant.

One problem: if we put the drift tube on a large TC, we have to suppress any outbreaks of plasma streamers, yet keep the terminal voltage far above a megavolt. Another problem: dielectric heating of glass can "turn on" the electrolytic conduction effect, where if the wattage of a large TC is involved, would cause the glass to burn through and perforate within seconds. Careful shielding of portions of the drift tube would be needed, but the shielding geometry must still allow a multi-megavolt potential drop to exist within part of the drift tube. I have several ideas to try.

And again: experiments with megavolt x-rays and MeV electrons either require very thick and expensive shielding, or need a piece of farmland (with safety provided by distant remote control and video observationof the devices in operation.)

Heh. Does anyone here live in... Colorado Springs?

quicksilver

Mon Jul 05 2010, 06:55PM

Registered Member #1408 Joined: Fri Mar 21 2008, 03:49PM
Location: Oracle, AZ
Posts: 679

The guy is banned; the thread is history.
Interestingly the entries on "Runaway Breakdown" in "Wiki" (the encyclopedia that the public writes.....) are not written by the OP.

dmg

Tue Jul 06 2010, 06:01AM

Registered Member #2628 Joined: Fri Jan 15 2010, 12:23AM
Location:
Posts: 627

proximity 3 wrote ...

There seems to be some sort of ritualistic initiation rite that some newbies are put through here especially if you bring up topics that aren't generally found in a college text book. Progressive thinking isn't prohibited here, but it isn't encouraged much either (again, my opinion). Middle-of-the-road topics seem to be the safest topics because nobody gets upset at them or lables them pseudo-science... but if you choose to mention topics that are not already generally known science or can't be goggled... be prepared for a few members or moderators to give you a hard time.

what?

anyway, since we are on the topic of ancient threads, anyone know what this guy got banned for?

803

Tue Jul 06 2010, 08:21PM

Registered Member #2807 Joined: Fri Apr 16 2010, 08:10PM
Location:
Posts: 191

he pissed off everyone and became a rebel with CM. Then the problem was solved:-D by by

klugesmith

Tue Jul 06 2010, 08:28PM

Registered Member #2099 Joined: Wed Apr 29 2009, 12:22AM
Location: Los Altos, California
Posts: 1714

On Fri Mar 30 2007, 08:50AM

CM wrote ...
...
There seems to be some sort of ritualistic initiation rite that some newbies are put through here especially if you bring up topics that aren't generally found in a college text book. Progressive thinking isn't prohibited here, but it isn't encouraged much either (again, my opinion). Middle-of-the-road topics seem to be the safest topics because nobody gets upset at them or lables them pseudo-science... but if you choose to mention topics that are not already generally known science or can't be goggled... be prepared for a few members or moderators to give you a hard time.
...

On Mon Jul 05 2010, 10:56PM (PDT = UT-7h)

proximity 3 wrote ...
There seems to be some sort of ritualistic initiation rite that some newbies are put through here especially if you bring up topics that aren't generally found in a college text book. Progressive thinking isn't prohibited here, but it isn't encouraged much either (again, my opinion). Middle-of-the-road topics seem to be the safest topics because nobody gets upset at them or lables them pseudo-science... but if you choose to mention topics that are not already generally known science or can't be goggled... be prepared for a few members or moderators to give you a hard time.

Troll alert!

"Proximity" is evidently a plagiarist, or CM by another name. I'm pleased that the practice he protests has persisted.

Chris Russell

Sat Jul 10 2010, 05:11AM

... not Russel!
Registered Member #1 Joined: Thu Jan 26 2006, 12:18AM
Location: Tempe, Arizona
Posts: 1052

Sorry folks, but the truth is far less interesting. Both new posters to the thread were spambots; their text ripped from earlier posts so that they could link to their spammed sites in their signatures.

The OP of this thread is long gone; I'll go ahead and padlock this thread now, as no further useful discussion is likely to result.

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