The first use of “8CDX” can be traced back to the Department of Commerce’s 1922 Callbook.   Below is a complete history of the 8CDX / W8CDX callsign:

1922-1924: 8CDX, Douglas Lewis, 2946 Zephyr Ave, Pittsburgh, Pa.  750W transmitter

1925-1927: 8CDX, Harry D. Loveland, 177 S. Mount Vernon Ave, Uniontown, Pa. 15W transmitter

1928: W8CDX, Harry D. Loveland, 177 S. Mount Vernon Ave, Uniontown, Pa. 15W transmitter

1930-1946: W8CDX, Elmer W. Ahrens, 705 Monroe St, Dunkirk, N. Y. (737 Main St., Dunkirk, N. Y in 1946)

1955: WN8CDX, Carl R. Thomas, 74 East Evergreen, Youngstown 7, Ohio

1959-1998: W8CDX, Carl R. Thomas, 74 E. Evergreen Av., Youngstown 7, Ohio / 82 Alverne Dr., Poland Ohio

2016: W8CDX, Karns City Amateur Radio Club (now Classic DX Association)