How to make your own pocket decoder You will need: • Scissors • Paper clip • Paper fastener or ‘brad’ to fasten the two paper pieces together • Crayons or colored pencils (optional) What you need to do: • Print out this page so you can cut out the wheels below • Put the smaller wheel on top of the larger wheel and use the paper fastener (brad) to attach them together at the dot • Unfold the fastener tabs underneath securely How to work the cypher wheel: To avoid confusion we will define some terms that we use to refer to the different kinds of phrases used in the decoding process. Sometimes we use the terms decode and decpher interchangeably but when you substitute each letter in a message for another letter it is actually called enciphering. A message that you can read and has not been enciphered is called "PLAIN TEXT". When it has been enciphered and is not readable then it is called "CIPHER TEXT". Sometimes a keyword is used to make a cipher more dificult to crack and is called "KEY TEXT". Here is a sample message for you to figure out. This is the cipher text that we made using the symbol for the key text. JOLKYNOVKHA XOCCBAOC KC AVOBR QFH The first step is to find on the inner wheel. This symbol kind of looks like the number 7. Line the symbol up with the A and B on the outer wheel. If you have done this correctly then the letter G on the inner wheel will be lined up with the letter A on the outer wheel. It is a good idea to write the enciphered message on a sheet of paper with lots of room around it and plenty of space between each letter. Then, as you decipher each letter you should write it below the corresponding letter of the cipher text. Now notice that the first letter in your cipher text above is J. Find the letter J on the outer wheel and see that it lines up with the letter D on the inner wheel. Write the D below the J on the cipher text. The next letter is O. Find O on the outer wheel and see that it lines up with the E on the inner wheel so write D below the O. Next is the letter L which lines up with the letter C. JOLKYNOVKHA XOCCBAOC KC AVOBR QFH DEC Follow the same procedure to decipher the entire message. Remember to find each letter in the cipher text on the outer wheel and use the matching letter on the inner wheel to make your plain text. Don’t get discouraged if it seems hard at first – just keep practicing.

How to make your own pocket decoder - KPNhome.kpn.nl/penn0071/pocketdecodermakeyourown.pdfSometimes a keyword is used to make a cipher more dificult to crack and is called "KEY TEXT"

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Page 1: How to make your own pocket decoder - KPNhome.kpn.nl/penn0071/pocketdecodermakeyourown.pdfSometimes a keyword is used to make a cipher more dificult to crack and is called "KEY TEXT"

How to make your own pocket decoderYou will need:

• Scissors • Paper clip • Paper fastener or ‘brad’ to fasten the two paper pieces together • Crayons or colored pencils (optional)

What you need to do:

• Print out this page so you can cut out the wheels below • Put the smaller wheel on top of the larger wheel and use the paper fastener (brad) to attach them together at the dot • Unfold the fastener tabs underneath securely

How to work the cypher wheel:

To avoid confusion we will define some terms that we use to refer to the different kinds of phrases used in the decoding process. Sometimes we use the terms decode and decpher interchangeably but when you substitute each letter in a message for another letter it is actually called enciphering.

A message that you can read and has not been enciphered is called "PLAIN TEXT".When it has been enciphered and is not readable then it is called "CIPHER TEXT".Sometimes a keyword is used to make a cipher more dificult to crack and is called "KEY TEXT".

Here is a sample message for you to figure out. This is the cipher text that we made using the symbol for the key text.

JOLKYNOVKHA XOCCBAOC KC AVOBR QFH

The first step is to find on the inner wheel. This symbol kind of looks like the number 7. Line the symbol up with the A and B on the outer wheel. If you have done this correctly then the letter G on the inner wheel will be lined up with the letter A on the outer wheel.

It is a good idea to write the enciphered message on a sheet of paper with lots of room around it and plenty of space between each letter. Then, as you decipher each letter you should write it below the corresponding letter of the cipher text.

Now notice that the first letter in your cipher text above is J. Find the letter J on the outer wheel and see that it lines up with the letter D on the inner wheel. Write the D below the J on the cipher text. The next letter is O. Find O on the outer wheel and see that it lines up with the E on the inner wheel so write D below the O. Next is the letter L which lines up with the letter C.

JOLKYNOVKHA XOCCBAOC KC AVOBR QFHDEC

Follow the same procedure to decipher the entire message. Remember to find each letter in the cipher texton the outer wheel and use the matching letter on the inner wheel to make your plain text.

Don’t get discouraged if it seems hard at first – just keep practicing.