Re: Tesla Coil RF interference

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 


We also conducted this experiment with a large 18 inch dia. coil (8 ft.
spark at 7.5 kVA).  Using an identical coil with a 30 x 7.5 inch toroid as a
receiver, with a good ground, we were able to light an 18 mm neon tube at a
distance of 4,250 ft. from the transmitting coil.  Freq was 170 KHZ.  The
lamp was steady brightness all along the tube.

I was quite surprised.  I only expected perhaps 100-200 feet.  Then we
loaded the coil on the back of an open pickup a drove away stopping to drive
a short 12 inch ground spike as we tested.

Dr. Resonance

 >
 > Actually Scott, I went back and measured it, it was 24'. The Neon tube (8"
 > long) was made at a sign company down the street from where I live. The
 > tube only glowed red and could be seen with the lights out. The streamer
 > length was only about 4". The primary was wound around the same coil form
 > and actually attached to the secondary. I am told that this is actually an
 > ODIN coil. I used a single glass plate capacitor about 20"x12" x .18"
with
 > aluminum foil for plates. The spark gap was static and consisted of just
 > one large gap. If I attached a wire or a small coil of wire to the end of
 > the tube like an antenna the tube would glow bright red and could be seen
 > with the lights on.
 >
 >
 > My 6" dia. Pig powered coil would not do this, even though I was getting
8'
 > streamers from it. I really believe that it has a lot to do with
frequency.
 > If you have any additional questions please feel free to contact me.
 >
 >
 >
 > Paul S. Marshall
 >
 >
 >
 >
 >
 > >From: "Tesla list" <tesla-at-pupman-dot-com>
 > >To: tesla-at-pupman-dot-com
 > >Subject: Re: Tesla Coil RF interference
 > >Date: Thu, 20 May 2004 16:52:10 -0600
 > >
 > >Original poster: "Scott Hanson" <huil888-at-surfside-dot-net>
 > >
 > >Paul -
 > >
 > >Can you supply some additional, specific details on your tiny 1-1/2" coil
 > >that was able to light neon tubes from 30 FEET away? By "30 feet away"
you
 > >mean 30 MEASURED linear feet between coil and neon tube, correct? This is
 > >not a typo? What was the free-air streamer length the coil itself could
 > >produce at maximum output? What was the value of the tank capacitor, and
the
 > >charging voltage?
 > >
 > >Can you describe the "neon tube" that was used? Length, diameter, shape,
 > >etc?
 > >
 > >When you say "light" the tube, do you mean a barely detectable flicker
that
 > >could be seen only in a dark room, or that the tube was clearly glowing
from
 > >end-to-end, or something else? Was the tube held in the hand, with both
 > >electrodes in free air, was one end grounded, etc? Are you certain the
fill
 > >gas was neon?
 > >
 > >Given the inverse-square law for RF power, illuminating a neon tube at 30
 > >feet seems, well, incredible. I've seen much larger coils (5-6 foot
streamer
 > >length) illuminate conventional 48" fluorescent tubes and neon sign
tubing
 > >at 10-15 feet, but nothing past 20 feet.
 > >
 > >More specific information would help everyone understand the mechanism
 > >behind this extraordinary observation.
 > >
 > >Regards,
 > >Scott Hanson
 > >----- Original Message -----
 > >From: "Tesla list" <tesla-at-pupman-dot-com>
 > >To: <tesla-at-pupman-dot-com>
 > >Sent: Wednesday, May 19, 2004 7:18 AM
 > >Subject: RE: Tesla Coil RF interference
 > >
 > >
 > > > Original poster: "Paul Marshall" <klugmann-at-hotmail-dot-com>
 > > >
 > > > I noticed this with small out of tune coils. Actually, the first coil
I
 > > > ever built was on a 1 1/2 inch form. At low power 450 watts, It would
 > >light
 > > > a neon tube at a distance of 30 feet. Metal objects that were not
grounded
 > > > had induced voltages as high as 3kV. My neighbors complained about
their
 > >TV
 > > > just looking like a blizzard. On the other hand my 6.5" coil running
at 10
 > > > kW wouldn't do that and I was getting 8' streamers. I think it has a
lot
 > >to
 > > > do with frequency. You seem to have just hit the right one.
 > > >
 > > >
 > > >
 > > > Paul S. Marshall
 > > >
 > > >
 > > >
 > > >
 > > >
 > > > >From: "Tesla list" <tesla-at-pupman-dot-com>
 > > > >To: tesla-at-pupman-dot-com
 > > > >Subject: Tesla Coil RF interference
 > > > >Date: Mon, 17 May 2004 23:03:04 -0600
 > > > >
 > > > >Original poster: "Gary Weaver" <gary350-at-earthlink-dot-net>
 > > > >
 > > > >I have noticed when I fire up my 10" coil it sets off motion detector
 > > > >light, security alarm systems, causes TV interference for 5 blocks it
all
 > > > >directions of my house.   The neighbors security lights flash on and
off.
 > > > >I can hear several alarm systems going off all over the neighbor
hood.
 > >I
 > > > >took my portable 4" TC to work and fired it up and the telephone
system
 > >was
 > > > >static so loud it was like putting my ear up to the spark gap.  Even
the
 > >PA
 > > > >system sounds like the spark gap amplified to 50 watts.  I don't own
a
 > >cell
 > > > >phone so I was wondering what effect a TC has on a cell phone?   Does
it
 > > > >have any effect on a cell phone at 20 ft, 50 ft, 100 ft???
 > > > >
 > > > >Gary Weaver
 > > > >
 > > >
 > >
 >
 >
 >