Tuesday, June 9, 2015

Substitution Codes - Secret Decoder Rings

          If you have read the post on substitution codes, you know that you can code and decode using two strips of paper that have the alphabet on them. You can slide one strip right and left to align the correct letters for the amount of offset in the message, like this:

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

 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

The green strip has been moved over two letters, so each coded letter is 2 more in the alphabet. Notice that we had to take the extra letters in the green strip and place them at the beginning. This is what happens automatically if the strips of the letters are on a ring. A ring! We could call it a decoder ring!!!

Little Orphan Annie's Secret Code Pin

The first secret code pins were made by the makers of Ovaltine (a chocolate drink). They were featured on their radio program, Little Orphan Annie, in 1934. The sponsor started a fan club, Radio Orphan Annie's Secret Society. It had a membership pin and a member's handbook. Inside the handbook was a very simple code (see substitution codes) that any one could learn to decipher (decode) and encipher (code) messages: each letter's position in the alphabet was given a number double its numerical position (i.e., A=2, B=4, C=6, ..., Y=50, Z=52).

                                                     Jonny Quest's Secret Code Ring

By the early 1960s, "secret decoder rings" were what people remembered (even if they were pins), so some people developed a few. The best of the lot was the PF Decoder Ring, which was on the Jonny Quest television show. It substituted letters for letters, and even had a secret compartment! Later, Kix cereal produced a Kix Secret Agent Decoder Ring, which was a cereal premium.

                                                     Midway School Secret Code Ring

We used a 3D printer to make up secret decoder rings for the kids in the 3rd grade. This is a design from Thingiverse . If you are interested, click on the name. The ring is called:

Caesar Cipher Decoder Ring Rounded by cymon

Published on December 21, 2011


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If you are interested in a decoder ring of your own and live in the Midway School area, drop me an email.

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