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An electrostatic diodes

why would you want to put a voltage multiplier or bridge rectifier on your Tesla coil?
  [vote for,

This is a idea without much merit, unless you are going to try to make a Z pinch machine in your garden shed, or make QG plasma in your Farnsworth fusser. It might be useful in line with the tank capacitor, as a one way spark gap, to stop the primary coil from resonating!

The invention [such as it is] is based upon Fridays ice pale experiment That all of the charge on a hollow conductor will collect on the out side.

You need a 7 or 8 cm bit of copper pipe such as that used I central heating systems. two lengths of high tension cable and some electricians tape.

Trim 3 mm of insulation off one of the cables and shape the end millimetre into a point, or set of points. Wrap electricians tape around the end 2 cm of insulated cable until it fits very snugly. Push the cable securely into the tube, making sure that the cables conductor dose not touch the mettle tube. Connect the other bit of cable to the out side of the tube.

That’s it, a high voltage device that aloes electrons to flow one way but not the other.

j paul, Jun 08 2011

Oliver Heaviside http://en.wikipedia.org/wiki/Heaviside
Read, absorb, and inwardly digest. You may be asked questions later. [8th of 7, Jun 09 2011]

Candidate for a Pullet Surprise http://www.paulhensel.org/teachspell
I have a spelling checker, / It came with my PC. / It plane lee marks four my revue / Miss steaks aye can knot sea. [notexactly, Mar 14 2019]


       Hmm. Either positive or negative charge collects on the outside of a hollow conductor, and a negative or positive charge collects on the extremities of a pointed conductor, which can in turn discharge either positive or negative ions. I'm not convinced that current will only flow in one direction.   

       Vacuum tube diodes are a bit like your device, but the cathode is heated, and can therefore emit electrons at a lower voltage, due do the thermionic effect.
spidermother, Jun 08 2011

       As I understand it there can be no charge of any sort on the inside of a hollow conductor. So if the central conductor is negative, the electrons pile up on the point until the voltage is high enough, spark across the gap then pass through the cylinder. When the current is flowing the other way, the electrons pile up on the smother outside curve of the cylinder, but will not move inwards. If the voltage gets high enough, then it will spark out away from the accumulated charge to a nearby earthed object.
j paul, Jun 09 2011

       Positive charge piles up on the point also. It's the magnitude of the potential difference that determines whether a spark will jump. It's just as easy for electrons to jump from the inside of the sphere at 0V to the point at 10,000V as to jump from the point at -10,000V to the inside of the sphere at 0V (disregarding any other effects, such as localised ionisation of the gas near the point, or thermionic effects, which are unlikely to change anything in this case)
spidermother, Jun 09 2011

       Oliver Heaviside must be spinning in his grave ... possibly fast enough to generate non-Newtonian effects.   

8th of 7, Jun 09 2011

       //SM //I think you may be wrong about it being equally ease for charge to move in either direction. The reason that the charge [elections] collects on the outside of a hollow conductor is that this is situation of lowest potential, that is the point at which it is as far from all of the other smiler charges as it can get. So a charge moving in over has to move up a potential gradient, but a charge moving out over is flowing down the potential gradient   

       A Van de Graff generator is an example of a device that takes advantage of this property of hollow conductors,
j paul, Jun 11 2011

       When considering charge distribution in a conductor, it's best to forget about electrons. Positive charge also distributes evenly over the surface of a (positively charged) spherical conductor. The situation is symmetrical with respect to charge.
spidermother, Jun 11 2011

       This is fascinating. the idea, is that electrons which are of course - accumulate on the outer surface, causing dc   

       then the discussion is, so where are the protons. my perception is that when the van de graff rubber band moves along the brush, the protons stay at the brush   

       this gives another possibility, what if you coat just part of the outer spherical surface of a van de graff generator with an electret. will the electret cause the actual moveable electrons to bunch up more creating areas of slightly higher current, which might of course mean they are more discharge susceptible, which means you can point at least slightly, the direction of the electrical effects   

       these electrical effects are made of electrons, so that is sort of a geometric surface diode.
beanangel, Aug 15 2012


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