From February 1946 to June 1949, Dyer was assigned to the Naval Security Station, 3801 Nebraska Avenue, Communications Support Activity in Washington, DC (precursor to the Naval Security Group) as chief of processing and technical director. In 1947, he was designated the first (?) Navy Special Duty Officer (Cryptology). Dyer was a leading member of the Navy contingent that joined the fledgling Armed Forces Security Agency in June 1949 and, along with Captain Laurance Safford, was in charge of all daily AFSA operations.
Taken from the National Security Agency website.