Re: electromagnetic shielding components

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: <davep@xxxxxxxx>

> Original poster: "JT Bowles" <jasotb@xxxxxxxxxxx>
>
> I currently have an ignition coil powered monopole tesla coil(nicely
> built). It is run off a 12v, that goes into a 555 timer pulsing
> squarewave into a 2N3055. This in turn pusles 12v into an ignition coil.
> I have  the whole igniton coil drive circuit, and the ignition coil in
> the  base of my coil - just 4 inches below my primary coil. I noticed
> while connecting the battery, sparks of up to 1/2" in length jump to  my
> hands (from the battery terminals). I know this isn't too bad for the
> drive circuit, because after a good 20 minutes of compiled use it still
> works. But, it cant be too good either.

> I am wondering if placing a sheet of steel directly underneath the top
> of the base (above the top is the primary) will at least hinder the
> electromagnetic field reaching the drive circuit.
    I would expect it to accomplish little.  The EM field will:
      calmly couple around the edge of the plate.
    and
       be on the wires passing thru, thus bypassing the
       added shield.

    Might be interesting top dig thru the archives at
     Faraday cage

> Or, will this sheet just waste vital energy from the primary field?
    Likely some.

> In addition, will that steel or copper sheet mess up my counterpoise
> effect, that I have bolted to the base of my coil?
    Not clear what the geometry is, here, how things are arranged.

    I'm guessing:

     coils
   (proposed shield)
     Drive Box
   Counterpoise

    ??

   Dunno if this helps.
    dwp