U.S. Army Spc. Judy Mattadeen, of the 101st Signal Battalion, Yonkers, N.Y., verifies linked communications between high-frequency radios being tested at Kozara Barracks, Banja Luka, Bosnia-Herzegovina, during Combined Endeavor 2009 on Sept. 9, 2009. Combined Endeavor, sponsored by Headquarters, U.S. European Command, is a communications and information systems interoperability test among Partnership for Peace participants, NATO members and other nations that focuses on planning processes, communications information systems and human interoperability and the development of a road map for future improvement among participants.