Jacob's Ladder

Jacob's Ladder

The earlier Jacob's Ladder I made was a wooden folding toy; this is the more famous electric one. They have nothing to do with each other.

My Jacob's Ladder does what people told me couldn't be done: I obtained over two feet of travel, with a nice spark using a neon sign power supply that "only" puts out 5000 volts (5kv). Also, no Gabriel Circuit on it. I did add a tiny twist of copper wire at the bottom of one of the rods just for kicks though. 

My unit is a used $4 Cenco 87208 5000v spectrum tube power supply. It was originally used to power various tubes for spectrometer testing. I actually got a free heart defibrillator testing machine with it to. All for less than five bucks!

For another $5 I got a spectrum tube for it!

I got this as a cheap $5.00 add-on amazon prime item!I hooked it to the Cenco power supply. It glows purplish and is awesome! The instructions that came with it say 5000v at around 10mA is good. You should only run it for about 30 seconds!I misplaced my tube holders that came with my power supply so I just soldered two wires to the end caps.I used a variac to supply power to the cenco power supply and the tube lights up at around 3-5 out of 10 on the variac knob. I had to be extremely careful unwrapping it: the instructions are wrapped around the tube and there is a glass nipple-spike sticking out the side that is super easy to break! Also, the center section is very thin and can break when you're pushing it into a tube holder fitting.

And here is the sherbet-orange helium tube I also got.

Here it is hooked up to my huge voltage divider (so it doesn't melt my multimeter). The deal was even better: it's putting out 6000 volts! There were two cords: wall plug and a remote power switch. I cut off the remote switch wires and closed the hole in the wiring by just joining two wires together.

This is a wire frame for holding folders in a file cabinet. I had two.

Now they're the rods for my Jacob's Ladder!

Here's the whole simple setup: direct attachment of the rods: no dangerous wires to melt. I kept adjusting and straightening the rods using the safe high voltage method: unplug the power supply and always have the plug in my left hand behind my back while working on the device.

Some devices have capacitors in them that can store deadly electrical charges for months, even after you unplug them! This unit doesn't (I looked). I also powered it up repeatedly and watched the voltage fall on shutdown: very quick, thus a few seconds after shutdown it's dead. Although the rods can get really hot from the spark.

Here's the transformer: only 5000 volts, which is enough for a Jacob's Ladder. The sound of even this low power, yet still lethal, transformer induced a fascinating noise that suits sounds like musical wind chimes.

Thinner rods might vibrate more and create louder "music" along with the stereotypical monster movie zapping noises.

The hardest part of this project was working up the courage to s flip the power switch on.

It was so scary we forgot to turn the camera sideways! Meow!