Note on Why 'F, V, X, Y' on the Hebrew Enigma Machine

摘要

Introduction. During my recent Fireside Chat (March 13th, 2021), I briefly introduced the concept of the 'Hebrew Enigma' (Fig. 1); I commented that it had the three Latin characters {F, X, Y} on its keyboard, lampboard, and plugboard, and I invited the audience to consider the question 'Why F, X, Y'? During the production of this document, it became clear that I had asked a slightly wrong question as there are four Latin characters involved, {F, V, X, Y}. What follows is my brief explanation. The Hebrew Enigma. The Hebrew Enigma is a fairly standard 3-rotor German Enigma except that it has been modified to support the 22-character Hebrew alphabet, although it retains the main design of using 26 letters throughout. An Enigma works by converting a letter typed on the keyboard into another letter which is displayed on the lampboard; note that an Enigma cannot encrypt any letter to itself.