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Re: Some more Questions on RF Interference and others



> 
>  1) What is the range of the RF Interference of a Tesla coil? I currently 
>  have no neighbours around me except across the street.

With the power of your unit, I don't think you will bother neighbors across 
the street.

>  2) Can a faraday cage be made out of the wire used for bird cages? or must 
>  it be a more fine mesh of wire? Also can the frame be made out of 
>  wood/plastic?

I have heard that the mesh size should be smaller than 1/4 of the wavelength. 
 In other words, just about any size mesh will do for a TC(assuming what I 
heard was corrrect).  Wood framing will be fine.  Just ground the cage.   One 
way to find out is to use a battery powered AM radio and see how far the 
interference can be picked up while your coil is operating. 

>  3)What is the minimum size of a faraday cage for my coil dimensions? Our 
>  ceiling is 3 meters high.

 You want it large enough to allow full discharge without hitting it, so you 
can see the full sparks.

>  4) Anyone got plans for building one? Especially one that can be 
dismantled 
>  in a few minutes?

sorry, no.  never bothered with one myself.
>  
>  5) Our ceiling consists of pressed metal plates (patterns), will that act 
as 
>  some kind of block to some of the RFI?

That would be if the metal is grounded in some manner.  

>  
>  6) I have this circut for a mains filter (got it somewhere on internet, 
>  can't remember where):
>  
>  AC in  -----CHOKE--------------------------to NST
>                     |   |
>                    --  --
>                    --  --
>                     |   |
>                     --------Ground
>                     |   |
>                    --  --
>                    --  --
>                     |   |
>  AC in  -----CHOKE--------------------------to NST
>  
>  Each choke, 30 turns of 3.15 mm wire on a 1" diameter iron rod (I cut a 
>  weightlifting rod for it, couldn't find ferrite cores except small toroid 
>  ones)
>  Caps: 630V, 220nF each (maybe use bigger caps?)
>  
>  With this circuit I still get feedback, can this go out of our house wire 
>  and into the powerbox that distribute to the rest of the neigborhood? I 
>  don't care about our own radios/TV in the house since I unplug the TV and 
>  usually only run my coil at odd hours and for short durations.

I don't think you can supress 100% of the feedback.  You can reduce it 
dramatically using a filter circuit.   It could feed back to the mains 
causing some interference.   My television will have "snow" on the screen if 
it is on while my TC is running, similar to when a vacuum cleaner or power 
saw is running while the TV is on.

>  
>  7) Can I use the lighning protection unit/surge protector/mains filter of 
my 
>  pc to filter the mains? Must I connect it in reverse for this?
 
Never tried this.  It seems as though you would pop the breaker in it with 
any surges.
>  
>  8) We got suspended wooden floors in our house? Will that make things a 
bit 
>  safer in case of a hit from the secondary?

I doubt you will have any serious problems with a coil powered by a 12/30 
neon.  I keep a fire extinguisher nearby, but have never had any trouble.  I 
run my coil with 15kV and 120 ma in an upstairs bedroom in my apartment.  My 
next-door neighbor says she has never noticed me running it(just asked her 
yesterday).   I haven't even used a filter circuit or a faraday cage.  I just 
try to run it when no neighbors are home. 
  
>  9) How do you convert caps rated in nanoJoule to farads?
>  
0.5*C*V^2 = stored energy, in Joules.   C is in Farads
Hope this helps
Mike