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Mystery Cache

Digital Electronics : Theory

A cache by mjouk Send Message to Owner Message this owner
Hidden : 11/8/2012
In Eastern England, United Kingdom
3 out of 5
2 out of 5

Size: Size: regular (regular)

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Geocache Description:

We're all used to using the digital electronics in our GPS receivers to find caches, but to solve this puzzle you'll have to work out how a simple digital circuit works.

Caveat cacher

The coordinates above point to the middle of a field. There is nothing to see there.


Congratulations to TelemachusGB for being FTF.

Digital Electronics : Theory

The diagrams below show arrangements of logic gates, flip-flops, and seven-segment displays.

To find out where the cache is hidden, you simply have to work out what you'd see on the displays were you to build the circuits.

The circuits are quite simple, so pencil and paper are probably the best tools for the task, though you could actually build them! If you do stick to pencils, then the worksheet below might help:

You can check your working at geocheck:

If you've enjoyed this cache, you might enjoy its companion Digital Electronics : Practical. If you are planning to do that one, please borrow a kit of components from this cache when you sign the logbook.

Additional Hints (Decrypt)

Ba gur yrsg-unaq fvqr bs gur pvephvg qvntenzf gurer ner fbzr grfg cbvagf. Lbh zvtug fgneg ol jbexvat bhg jung'f unccravat gurer.

Gurer ner urycshy svaqvat uvagf ba Trbpurpxre.

Decryption Key


(letter above equals below, and vice versa)



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Last Updated: on 9/23/2017 2:24:18 AM Pacific Daylight Time (9:24 AM GMT)
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