TheCodeBreakers
hours a day on at least some of its two dozen receivers. Sometimes just
the circuits being used would give Japanese intentions away. On Biak in
1944, the unit quickly learned that messages on a certain frequency
invariably preceded an evening air raid—a bit of foreknowledge that
enabled one member to collect regularly on sure-fire bets with a sergeant
from a nearby outfit. Other times the 20-odd nisei in the unit intercepted
Japanese cleartext. Usually, however, the radiomen typed out the coded
intercepts and handed them to a traffic analyst. Most of the messages
reported planes flying from one point to another, and the analyst, by a
study of call-signs, could tell which unit and which points were meant.
The 15
cryptanalysts had the mechanical task of stripping the additive from
codes that had been solved at C.B. Each day a report summing up the
unit's conclusions went rearward to 5th Air Force headquarters, to which
annaabi.ee 
