While N and A were chosen for American military radio stations, W and K were designated specifically for commercial use. ... read more
Under the treaties between the United States and other countries, each licensed radio station must have a call sign. Early in the history of the broadcasting industry, many stations had only three call letters, and, to this day, some of those early calls (such as KFI in Los Angeles, WLW in Cincinnati, WSB in Atlanta, etc) are still in use. read more
The United States, for example, is assigned three letters--N,K, and W-- to serve as initial call letters for the exclusive use of its radio stations. It also shares the initial letter A with some other countries. read more
ALL radio stations and television stations in North America have a call sign that is either three or four letters. In the US, they begin with W, K, N, or A - N & A are for military use. In Canada, they begin with C. read more