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Hello Seth, Unfortunately, Jacob's Ladders use high voltage at moderate current, and most also require power from the 120 volt wall socket. So, it must always be used under adult supervision. Also, the Jacob's Ladder (JL) must be designed in such a manner that curious little fingers can't access parts that have either 120 volts or high voltages. The simplest way to make a JL is to use either a small neon sign transformer (NST) (such as a 9,000 or 10,000 volt 20-30 mA or a 10,000 volt 23 mA oil burner ignition transformer (OBIT) to provide the high voltage. It's also possible to make a JL using an ignition coil, but this is a bit more difficult. The HV transformer should be fully enclosed within a simple wooden box. The wires making up the "V" for the ladder should also be fully enclosed within a clear Plexiglas so that it can be seen, but not touched. Leave the bottom and top of the tube open to allow the hot air to freely circulate and escape. The wires can be made from coathangers, small diameter copper tubing, or even solid copper grounding wire, etc. A Jacobs Ladder is sometimes called a climbing arc. It relies upon the facts that hot air rises, and that hot air is also an excellent electrical conductor. As Wikipedia (the online encyclopedia) explains, "A Jacob's ladder is a device for producing large sparks. The spark gap is formed by two wires, approximately vertical but gradually diverging away from each other towards the top. When high voltage is applied to the gap, a spark forms across the bottom of the wires, rapidly changing to an electric arc. The arc behaves almost as a short circuit, drawing as much current as the electrical power supply can deliver, and the heavy load dramatically reduces the voltage across the gap. The heated, ionized air rises, carrying the current path with it. As the trail of ionization gets longer, it becomes more unstable, finally breaking. The voltage then rises and the spark re-forms at the bottom of the device. This cycle leads to an exotic-looking display of electric cyan or blue sparks which is often seen in movies about mad scientists." Here are some web sites that you may find helpful in designing your own JL: Good luck, and remember to please play safely! -- Bert --
: Hello,
:
: I was wondering if anyone had any good references for the Jacob's Ladder
: suitable for kids 10 years old or so...something with theory that can be
: understood. I appreciate any help...if you can, please email me at
:
: huskerdooo @ yahoo .com (please remove spaces)
:
: Thank you,
:
: Seth
:
http://repairfaq.ece.drexel.edu/sam/jacobs.htm
http://www.sciencefirst.com/artcls/8.pdf
http://www.llund.com/jacob.htm
http://tesladownunder.iinet.net.au/Other_HV_stuff.htm#Jacobs%20ladder
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