Ever since I read Terry Pratchett and Stephen Baxter's The Long Earth, I wanted to build a stepper box. It took me a while to figure out the details. As it turns out, Willis Linsay's original stepper diagram (source) is less of a straightforward build than people want you to believe.

In this Instructable, I'll lay out the details of how you can build your own stepper. Once you reach the Earth of your choosing and decide to settle, you can still use it as a cool night light. That is, after you built the infrastructure for an electric power grid etc. Hey, no one ever said it would be easy!

Step 1: Build the Circuit

As in Willis Linsay's original stepper box diagram, the main component is the popular 555. Try to get a pre -June 19th 2012 (Step Day) part, as this seems to increase your chances of success. Don't worry about the potato yet. We'll first build the circuit. I had to improvise a bit. As you can see, the circuit is the well known monostable multivibrator timer. A piece of perfboard will do. The timing can be set from 11 seconds to about 18 minutes, so you can doze off in style. The circuit around transistor, Q1, R8, C2, adds a smooth on/off feature. For Leds, I used these cyan 3W I bought on Aliexpress. You can use more Leds as long as your transistor can handle the current. If need be, copy the section connected to pin 3 of the 555 multiple times. The power supply is a salvaged 5V cell phone charger.

Nothing is too critical about this circuit and most components can be tuned or changed around a bit. In fact, It is recommended to do so, as building a stepper box is a highly individual experience: what you put into it, will change how the stepper interacts with the Long Earth. It's weird like that.

Step 2: Build the Enclosure

For the enclosure you'll need the following materials:

Cheap photo cube
4 rubber sticky feet
Piece of acrylic tubing 2'' diameter to hold the tater and possibly a 'lid'
Glue
3 M4 bolts, nuts and solder pegs
3 springs, salvaged from old ballpoints
copper enameled wire for the coil
various stuff found on and beneath my desk

Again, nothing is carved in stone here, so you are encouraged to improvise!

Be careful when drilling holes in the plastic cube. I found this kind of plastic to be quite brittle.

Assemble the spud holder as shown in the picture. The lid is glued to the bottom. Wind the coil around the spud holder and connect to the spud hyperplane quantum contacts. The SHQC should be touching the spud lightly. Said spud must be fresh. Do not eat after stepping as it is reported that stepper-employed taters taste kinda bitter. No one knows why. However you can use it to start a potato field in the Earth of your choosing.

IMPORTANT NOTE: Each traveler needs their own box. If you plan on stepping with technically less savvy family members/young children/spouses etc., then you can build their steppers for them. It is however vitally important that they wind the coil themselves. Winding the coil really needs to be done by the individual who will step with that box. This is explained in the book.

Step 3: Label the Switch and Assemble the Box

As with winding the coil, prospective steppers should label their own boxes' switch. Something with how the technology interacts with human consciousness. Please,please please, do *not* mix up East and West!

Solder a paper clip to the circuit board. This holds a small folded printout of the schematic. Comes in handy for when you have to repair your box. Most failures are due to a flat potato, though.

Assemble the circuit in the box, solder the power leads to the connector, and the SHQC to the circuit. Get a fresh spud and close.

Once you reach an Earth you like, settle down and start a civilization. You can use your stepper box as a night light to remind you of your travels.

I hear East-28746 is nice this time of year.

Happy Stepping!