I really don't follow what the aim of your experiment is. That is what are you intending to do with the ionised gas once you have it?
Why do you need two wires?
And why wires?
These have significant inductance at high rise times.
Flat strips are better.
Rise times are adversely affected by the use of traditional diode-capacitor voltage multipliers, especially for repetitive waveforms.
I note you mentioned HV mosfets. If you can get high enough ratings you might like to investigate this article. An amateur might try valves as an alternative.
The MOSMAX voltage multiplier Wireless World August 1988 page 748 ff.
Everyday Electronics did a constructional article about air ionizers
EE Feb 1984 page 82ff
I wonder if another approach might be to strip and remodel the EHT supply from an old cathode ray scope.
These are more likely to be modular and suitable than a TV EHT.
Remember the usual HT/ EHT precautions and keep your other hand in your pocket.
Hi Thanks for coming back.
What I am considering trying to achieve is an impulse emf in space radiating away from the source. Gamma rays and Xrays have very short wavelength and high energy, E=hf. They are also not good for the health.
I want to investigate a possible current bunching effect mentioned by JJ Thompson, and "possibly" utilised by Tesla. When a current is switched off the current bunches causing a rise in electric field strength due to inertia of electrons. E= Q/(4.pi.Eo.r) The local charge Q bunches resulting in a very large impulse voltage which radiates outwards. This effect is momentary and very fast causing ionization in the air, possibly only due to very high voltage, but maybe due also to a very short pulse duration, ie an impulse. The air glows when electrons recombine with the ionized atoms. This momentary voltage is difficult to handle and can blow up switching devices etc.
Using 2 wires in parallel it may be possible to create a similar bunching effect.
To create a pulse with sufficient energy to ionise a gas is not easily possible with todays technology.
When two pulses of current pass each other in opposite directions, the magnetic fields will cancel, the local electric field will as a minimum double. What I want to try and investigate is will the charges slow in any way and bunch giving an intensified electric field, and ionize the air more efficiently, due to shortened wavelength and intensified voltage.
Two straight parallel wires are the easiest thing to envisage, however Tesla utilised a bifilar flat pancake coil which he claimed was 100 000 times more effective at generating radiant electricity(ionised air) than his standard system. Many different coil configurations could be used to cause a similar effect, from simple loops to all kinds of knotted type coils. What I wanted to investigate first was a simple system. 2 parallel wires is I think about as simple as the idea gets. Except perhaps using a standard tesla coil and resonating a current up and down the length of the tube to create a standing wave or multiple standing waves.
To ionize the air with any noticeable effect from pulses the frequency needs to go up, and the pulse lengths to come down. By forcing a bunching effect this might be possible. Tesla stated that he felt a physical pain when he was running his system, this sounds a little like the microwave none lethal weapon systems being developed today.
Once I have the basic idea on paper, I wish to start and investigate separating the ions by modulating magnetic fields in the ionized gas, or using static charged or electron rich materials to attract the ions. Some one posted on the engineering thread area ref ionizing gases in a vacuum, I alluded to my interest there, however I wish to use very high frequency and very short wavelengths if I can create them. Bifilar coils with opposing currents on them have very low inductance and will allow me to pulse them at very high frequency with little BEMF.
I take on board what you are saying about the valve technologies they were incredibly fast, I was surprised also to find just how fast the old crystal diodes were when I looked into them. I also fully understand the concept of using flat conductors in parallel to minimise inductive effects.
I want to force the current to bunch momentarily to create an impulse wave, that may ionize gas locally. Two 100A current pulses with a leading edge rise time of 1ns moving in opposite directions at 0.5c is a little difficult for me to analise, my maths is rusty. But given a pointer in the right direction I can work it out for myself, it doesn't take me long to come up to speed on a subject I once new well. I am not sure if relativistic effects would come into the calculation, JJ Thompsons stuff was before Einsteins ideas. I want to push the edge of what is achievable with electric field strength and impulse duration, to improve the rate of ionisation in air. running the circuit in a reduced atmosphere is a good way of prolonging the ion separation, perhaps using different gases will ionize more easily. Putting the circuit inside a metal enclosure is also a good idea, to prevent microwaving myself by mistake. Yes If I use HV I wont have an issue with microwaving myself, but other people have done that already. The U tube link under the engineering section I mentioned above shows some good examples of ionization ethods and is incredibly interesting to me, albeit at this stage a little more basic than what I have in mind, I will monitor it and see where he is headed.
Any tips on the maths would be appreciated, two charges travelling in opposite directions on two parallel wires how do the currents interact, possibly bunch(shorten wavelength) and peak(how how will the emf peak at.). I am looking specifically at the pulse interactions as they pass each other. A reflected AC wave along a transmission line will create a standing wave as it meets other waves going out. I am specifically interested in DC pulses travelling along a line.