To set the stage for the deception, in early November 1941 the Naval General Staff ordered the First Air Fleet and other ships, under the direction of the DF Control Center of the 1st Combined Communications (that is, radio intelligence) Unit in Tokyo, to establish a regular schedule of drill communications. From 8 November through the 13th, Akagi, Hiei (the flagship of the 3rd Battleship Division), and the 24th Division of Ships (Destroyers) were to communicate with the Tokyo communications center three times a day--at 0600, 1200 (noon), and 2000 (8 PM), all Tokyo time. The participation of the DF Control Center was significant, suggesting that it was monitoring the radio traffic for purposes of evaluating the transmissions for later imitation, as well as for security. (46)
On 15 November, the Combined Fleet discreetly substituted new drill call signs for the various task forces, including the Striking Force. (47) The stations involved in the radio deception were to use the old drill calls of the carriers, principally Akagi, and other ships of the Kido Butai for the next three weeks. These false communications were to be sent by regular radio operators from the major ships of the Kido Butai who had been sent ashore to bases at Kure, Sasebo, and Yokosuka. A communicator's "fist," or the characteristic unique way a radioman taps out characters on Morse keys, was a method of identifying operators and, by extension, their ships. So, when American listening posts heard the familiar fist of an operator known to have sent messages from Akagi, using that ship's call sign, they construed the carrier to be on the bearing taken of his transmissions--in this case, in the direction of one of the home-island bases.
I believe, however, I was rather specific - the message(s) along with its associated communications header is what I remarked upon; a true copy of the raw intercept.
Oh, Hanyok is now retired ... last NSA publication was with Mowry on "The Winds" saga.
Again, thank you, but I have this article, no raw message was provided.
Of course, Rochefort was there then - a tad more solid by these lights.