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Lock Master Mystery Cache

Hidden : 9/7/2009
Difficulty:
3.5 out of 5
Terrain:
3.5 out of 5

Size: Size:   small (small)

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Geocache Description:

A puzzle to do in the field. The first stage of this two stage cache is at the posted coordinates. Good luck!

I was introduced to this part of Pleasanton by Marky's Mars Cope Rift cache and was immediately struck by how beautiful it is up here. Since Marky archived his cache, I placed one up here to encourage others to visit the area. Because the local (teen) population has taken to littering in the area, CITO is encouraged, and I've left a few bags at the first stage for your use.

Reaching the first stage requires a short hike with a decent elevation change for the length of the hike, hence the terrain rating. Gaiters are recommended in the dry season. If you attempt this cache at night, please be careful as the terrain can be tricky.

When you find the first stage, you will have to recover the combination to a Master Lock. There are no clues to the combination. Instead, detailed directions are provided here on how to recover a Master Lock combination. Also, videos and instructions are available via the internet; you may want to watch one of the videos and/or practice at home before heading out into the field. I have reconstructed the instructions here for your benefit (with thanks and credit to jasond). Once you have the combination, the first stage has further instructions.


Step 1: Print this page and bring it with you. You will also want to bring a pencil.

Step 2: Locate the cache and retrieve the Master Lock.

Step 3: Pull the "U" part of the combination lock away from the dial and try to turn the dial in both directions. There should be a little play in the lock, but it will stick between two positions. Take note of the positions where the dial gets stuck, and write down the average of the play. For example, if the dial sticks on 19 and 20, you would write down "19.5"; if the dial sticks on 6.5 (i.e., between 6 and 7) and 7.5, then you would write down "7." Each time you write down a number, let the dial past the catch point to the next catch point and repeat until you've gone all the way around the dial. When you have gone all the way around the dial, you should have written 12 numbers, exactly 5 of which are whole numbers. Of these whole numbers, exactly 1 will be unique in the 1's place. This number is the third number in the combination.

Step 4: Divide the number from step 3 by four and write down the remainder. Starting with this computed remainder, write down a sequence of 10 numbers, each 4 greater than the previous (e.g., 0, 4, 8, ..., 36). This set of numbers includes the first number of the combination.

Step 5: You will again write down ten numbers. To see which number begins your series, look again at your remainder from the division in step 4.
If your remainder was 0, start with 2.
If your remainder was 1, start with 3.
If your remainder was 2, start with 0.
If your remainder was 3, start with 1.
Just as in step 4, you will write a series of 10 numbers, each 4 greater than the previous number. This set of ten numbers will include the second number of the combination.

You have now been left with 100 possible combinations. Don't complain. Without these directions, you would have been left with 64,000 possible combinations.

N.B. The rated size refers to the first stage. The final is a micro. Please be aware that the coordinates on the final might be a tad loose (not intentionally). Despite open sky, I had trouble getting a good signal and when I placed the cache I found the coordinates may be as much as 20' off. The hide is fairly traditional, no need to trespass.

Additional Hints (Decrypt)

[First Stage] Erzrzore, guvf vf n fznyy. Vg vf abg ba gur gerr, abe haqre gur gerr, ohg dhvgr arneol ba gur hcuvyy fvqr. [Final Stage] Erzrzore, guvf vf n zvpeb.

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)