Re: Ground current experiments

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Jon,

Neat!  This could be a great science fair thing in that people (the judges)
may not understand how it is possible to get arcs off the second coil.
Thus they will have to study his project to find out!  Many hypotheses
could be formulated and tested which they really like.  It is always fun to
have a Tesla coil thing in a science fair.  But it is even more fun to win
! ;-D

Mention "displacement currents" :-)))

Cheers,

	Terry


At 08:42 PM 3/2/2002 -0800, you wrote:
>The past couple of weeks I've been helping my grandson, (age 14), build a
>small battery powered TC for his school science fair. The coil we built is
>based on John Couture's 70kV model as described in his "Tesla Coil
>Construction Guide".
>
>The purpose of this TC project is to determine if wireless power
>transmission is possible.
>
>I did a search of the list archives and found a post by Richard Quick
>describing some ground current experiments he performed with a medium sized
>Tesla coil. I kind of doubted that we would be able to perform those
>experiments with our battery powered TC.
>
>Before we were too far along with the construction of the coil I lashed
>together the various components with alligator clip leads to see what we had
>for spark length, (around one inch), and to see if the ground current
>experiments were possible.
>
>I had already ordered and received 3, 4, and 5 inch copper spheres from
>McMaster-Carr. I poked around the loft and found an old 4x21 inch, (#22
>wire), secondary.
>
>The 4x21 secondary topped off with a 5-inch sphere just happened to resonate
>pretty well with our TC's 3.5x13 inch secondary, (#28 wire), topped off with
>a 3 inch sphere.
>
>I covered the top of our work table with aluminum foil to act as a
>counterpoise and placed the 4x21 coil with it's 5 inch sphere about 1 foot
>from our lashed-up TC.  Both the "transmitting" coil and the "free" coil had
>the bottom of their secondaries connected to the counterpoise.
>
>When I fired up the transmitting coil I was totally amazed! The experiment
>worked beautifully! We were getting ½ inch sparks off of the free coil's
>sphere! With the free coil placed 15 feet away from the transmitting coil,
>(it's base still connected to the counterpoise), we were able to easily
>light a neon tube and could draw a tiny arc to a ground rod!
>
>So, if you're looking for some TC entertainment, (and education), I highly
>recommend Richard Quick's ground current experiments. Search the archives
>for "Tesla Experiments", December 1994.
>
>I don't know if what we did qualifies as "transmitting power", but we did
>manage to produce a spark from the free, "receiving coil" solely through the
>action of ground currents.
>
>My grandson plans to show that although power can be transmitted using Tesla
>coil ground currents doing so in this age of electronic everything would be
>completely out of the question. Using a AM radio he is going to show just
>how much interference a small Tesla coil, (around 18 watts), can generate!
>If this Tesla coil can drown out stations on the lower end of the AM dial
>100 to 200 feet away, (it does), just imagine how much havoc a TC the size
>Tesla was constructing at Wardenclyffe would cause!
>
>Our coil did scramble, (temporarily I hope), my WWVB wristwatch! I had
>better bury this watch in a copper lined lead vault when I fire my 10 inch
>pig powered coil. Just happens to resonate at 63kHz! Might be too much for
>the 60kHz watch receiver!
>
>Ok, enough for now.
>
>Jon Rosenstiel
>
>
>