Geocaching Transposed - Treasure chest on the go, Part 1
Once somebody told me that Computer Engineer is a poor profession - for creating presents for family and friends. Painters, sure, they can easily draw a picture and give it away. Musicians, yes, they can play a nice little tune for a birthday or even dedicate a whole hymn to a friend. But who likes surprises involving computers and software? I may agree, that some options may be a bit geeky, but others may be suitable for everyone.
On of these is a Geocache Transposed (GCT).

Geocaching is a well known hobby today, driven by cheaper and GPS devices integrated into mobile phones. For geocaching the so called caches are hidden at remote locations, while the coordinates are public. Using a GPS device, the cache has to be found and in most cases items inside the cache swapped. A GCT box flips this concept upside down.

The geocache transposed is the cache moving around. Think of your childhood, playing pirates on the hunt for treasures. This time you carry the treasure chest with you and need to solve the riddle of finding the right location.
The box itself is locked, inside sits a GPS receiver and the box only opens when activated at a certain spot on the world. At the wrong location, the box simply displays the distance to the target, letting you guess where exactly to go. The term Reverse Geocache for this and the original concept has been coined by Mikal Hart in 2009:
He designed the box as a present for his friend’s wedding and created a huge buzz about the idea, being romantic and fun for geeks at the same time.

The geocache transposed is a great personal gift, for weddings, birthdays or anniversaries. The process of creating your own box, selecting the secret location and observing the attempts to solve the riddle provide a huge source of fun. And its reusable when programming for a new secret location. After reading the original postings about the reverse geocache story, I had to build my own. The following posts will describe my process; maybe you will use them as an inspiration for your own derivative of yet another puzzle box.

Part 2 about the hardware parts can be found here:
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