April 21, 1931
Executive Order No. 5197-A, dated September 30, 1929, entitled "Assignment of Frequencies to Government Radio Stations," is hereby amended so as to delete the assignment to the Navy of 68 kc.
HERBERT HOOVER
The White House,
April 21, 1931.
Herbert Hoover, Executive Order 5605-A—Radio Frequencies Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/376099