[156] Communications Intelligence Summary, 17 November, 1941
 
General.-Traffic volume normal with receiving conditions good. More  traffic with single call heading appeared on the broadcast circuit.  These dispatches numbered serially and each call different but all  fitting the same line in the call garble table. Since these messages are  transmitted each hour on the hour and are of approximately the same  length it appears that they are drill messages. It is feared that they  constitute a test of straight broadcasting without a heading. Since none  of this traffic has been found going in to Tokyo it is probably   originated in the Navy Ministry. Very few messages of general address  were noted. Tactical circuits in the Mandates were heard during the day  with radio Saipan controlling.
Combined Fleet.-No movement from the Kure area of any major portion of  the First or Second Fleets. The CinC. Second Fleet very active as an  originator today. He continues to address units which are most normally  under his command. He also addressed the CinC. Third Fleet, Paloa  Forces, and the Chief of Staff Fourth Fleet.
Third Fleet.-Inactive at Sasebo. The Staff Communication Officer of  Third Fleet was addressed by the R. N. O. Paloa.
Fourth Fleet.-The greater part of the activity in the Mandate area  centered about the Third Base Force at Palao and the Sixth Base Force at  Jaluit. Both these activities originated traffic.
Air.-The Commander of the Combined Air Force remains in Takao and was  addressed frequently by SAMA, HAINAN and was in two instances addressed  by the Fourth Fleet. The carriers are mostly in the Kure-Sasebo area  with the exception of a few which are operating in the Kyushu area.
China.-Sama was again active today with dispatches to the Combined Fleet  Staff, Combined Air Force, Third Fleet and Bako. The R. N. O. Taimoku  addressed a dispatch to CinC. China, Sanchow Island Sama, Bako, CinC.  South China, and Chief of Staff Combined Air Force.

 

 (FROM: U.S. CONGRESS JOINT COMMITTEE ON PEARL HARBOR ATTACK HEARINGS; PT.  35, THE CLAUSEN INVESTIGATION, PP. 62-81. EXHIBIT "A" DAILY COMMUNICATION INTELLIGENCE SUMMARIES)