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We know that metal halide lamps and other HID lamps (like xenon/mercury arc ones) require 2-30kV+ spark to initiate discharge. Handling these voltages is not easy, and I am thinking if it's possible to initiate discharge by applying radiofrequency on the electrodes (for example 13.56 MHz) for a short time, just like in induction lamps or plasma etching chambers?

How does required power depend on gas pressure? Do I just need higher amplitude to excite high-pressure lamp or it's just impossible?

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The ignition of such discharge lamps is done by "high" frequency since long. But using 13.565 MHz for that is nonsense, because You invite a lot of short-wave problems without any profit. The ignition works at frequencies from some kHz to some dozen kHz. Gas pressure: only Xenon high pressure lamps have really high (some bars) pressure before start. All other lamps have not more than some millibars or less.

And: Power/pressure is a question of someone lacking simplest gas discharge basics. To ignite You need a voltage, and after that some current, µA or in extreme cases some milliamperes are sufficient. The main voltage source takes over and drives the lamp warm within some seconds or minutes.

Generally: Why do You try to reinvent wheels? The mere fact that millions of discharge lamps are around in the world says that ignition has been solved in some way.

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13.56Mhz is a standard frequency for industrial applications, so RF emission should not be a (big) problem there. Am I missing something, but I had an impression that most of these lamps use dumb electrical brakedown during a single peak. Going for brakedown in 'cold state' is something I am trying to avoid. –  BarsMonster Apr 26 '11 at 12:36
    
I want to reinvent the wheel because this should be more economical, reliable and safer. Electronics for 2kV+ is just too complex & expensive. –  BarsMonster Apr 26 '11 at 12:38
    
""because this should be more economical, reliable and safer."" Aha, I see You will be/are a real engineer: "I have a solution! Where is the problem?" ""Electronics for 2kV+ is just too complex" shows You do not have knowledge of electronics. I recommend anpother time to inform You on "state of the art" before You try to invent better things. –  Georg Apr 26 '11 at 12:53
    
This is not for job, this is for hobby. Hence, I don't have many 'production' limitations. I just want to avoid high voltage here and that's it. If majority of industry uses different approach - that's fine with me, but this still is not what I am trying to achive. –  BarsMonster Apr 26 '11 at 13:41
    
Still not a good aproach, it seems You want to replace frequency for voltage, what makes You think that this works? –  Georg Apr 26 '11 at 19:07
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