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Step 3FAILED LADDER
Like I said before, I originally attempted to build a ladder for the electricity to climb. I couldn't get it to work after a lot of time fiddling with it. I don't know if there just isn't enough voltage produced by a CRT to have it work effectively?
I built the ladder using wood dowels and copper tubing. The spacing of the tubing, the height off of the board, the spread at the top were all touchy and too critical. I could only get the arc to go up about 4 inches and most of the time the arc stayed where the tubing was closest. I was not impressed. After doing a little research online, I found out that:
A Jacob's Ladder works on the principle that the ionized air in the arc is a lower resistance than the air around it and heated air rises. The arc strikes at the point of lowest breakdown voltage - the small gap at the bottom. The heated plasma rises and even when it is an inch or more in width is an easier path for the current to follow. Eventually, the gap becomes too wide, the arc extinguishes and is reestablished at the bottom.
The gap between the electrodes at the bottom of a Jacob's ladder can be critical. Too wide and the arc won't strike, and too narrow and it won't make it all the way to the top. The lower voltage makes the gap even more critical. I found a slight enhancement that is supposed to work. It's simply a third electrode placed between the strike gap at the bottom of the vee. It is connected to either one of the main electrodes via two 1M ohm high voltage resistors.
When an arc should occur, the following happens...The voltage on the middle electrode floats to the potential of the electrode it's connected to via the resistors. It's easy for an arc to jump the short distance from the other electrode to the middle one. When an arc has struck and current is flowing, the voltage on the middle electrode flies up due to the high resistance value. The combination of high voltage at the middle electrode and the ionized path makes the arc strike all the way across.
That all sounded too complicated for the time I wanted to spend so I chose plan B...
I built the ladder using wood dowels and copper tubing. The spacing of the tubing, the height off of the board, the spread at the top were all touchy and too critical. I could only get the arc to go up about 4 inches and most of the time the arc stayed where the tubing was closest. I was not impressed. After doing a little research online, I found out that:
A Jacob's Ladder works on the principle that the ionized air in the arc is a lower resistance than the air around it and heated air rises. The arc strikes at the point of lowest breakdown voltage - the small gap at the bottom. The heated plasma rises and even when it is an inch or more in width is an easier path for the current to follow. Eventually, the gap becomes too wide, the arc extinguishes and is reestablished at the bottom.
The gap between the electrodes at the bottom of a Jacob's ladder can be critical. Too wide and the arc won't strike, and too narrow and it won't make it all the way to the top. The lower voltage makes the gap even more critical. I found a slight enhancement that is supposed to work. It's simply a third electrode placed between the strike gap at the bottom of the vee. It is connected to either one of the main electrodes via two 1M ohm high voltage resistors.
When an arc should occur, the following happens...The voltage on the middle electrode floats to the potential of the electrode it's connected to via the resistors. It's easy for an arc to jump the short distance from the other electrode to the middle one. When an arc has struck and current is flowing, the voltage on the middle electrode flies up due to the high resistance value. The combination of high voltage at the middle electrode and the ionized path makes the arc strike all the way across.
That all sounded too complicated for the time I wanted to spend so I chose plan B...
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Mar 27, 2008. 12:45 PMdorit82
says:
The EHT from the flyback transformer is around 25.000V DC. I think Jacobs ladder needs AC to work. A neon sign transformer is the usual tool for this kind of project.
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Mar 29, 2008. 5:17 AMtech-king
says:
dc works fine for a ladder.
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Mar 26, 2008. 10:39 AMLevetate
says:
i dont think you know what you are doing..........
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