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Broad River Cryptography #3: Homophonic Cipher Mystery Cache

This cache has been archived.

profzoom: This puzzle series was an absolute blast to put together, and congratulations to the brave few who went through the effort to solve them! The original goal was to have 15 caches forming geoart in the shape of the Greek letter/mathematical constant pi (π), but I never did get around to finishing those last two puzzles.

Due to the low find count and difficulty of keeping all 13 caches maintained, I've decided to archive the series.

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Hidden : 2/1/2019
Difficulty:
4 out of 5
Terrain:
1.5 out of 5

Size: Size:   small (small)

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Geocache Description:


The purposes of this geoart series are twofold: to bring cachers to the watershed of the North Fork of the Broad River in Stephens and Franklin Counties and to serve as an introduction to the fascinating field of cryptography.


The big problem with simple substitution ciphers is that they're vulnerable to frequency analysis. For example, there's a good chance that the most common letter in the ciphertext corresponds to "E", the most common letter in the English language.

How can we get around this weakness? Instead of just using one letter to encrypt "E" (and the other common letters), we use two or more! Of course, since there are only 26 letters in the English language and we've already used them all, we need to use new symbols, like numbers, upside-down letters, or something more creative. This added twist turns a simple substitution cipher into a homophonic cipher.

For example, we might encrypt the word "GEOCACHE" by "M2BTS8LJ". The letter "E" is encrypted as either "2" or "J", and the letter "C" is encrypted as either "T" or "8".


To find this geocache, decrypt the message below using a homophonic cipher.

FZC2N 2NPC2S LZRC TG7FTS FPF7 TGZ TNC77 TGZ GHQ2 HPONTS TNCH7 QPX277F AHCZ LPEH ZF7


Congratulations to Andrewsfamily78 for FTF!

Additional Hints (Decrypt)

ybpx a ybpx haqre n ebpx

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)