Because of royalties/copyright issues, you will see that you cannot listen to many All of us radio stations (which play music) when you are beyond your USA - this includes all CBS owned and operated r / c & iHeart stations. 

THE UNITED STATES radio scene differs from that generally in most other areas of the world. One of the main variations may be the naming of the stations. US r / c use "call-letters" (similarly to Canadian r / c) rather than names. These call letters usually comprise three or four 4 letters, such as for example "WJR" or "KVST". In most cases (with a few exceptions) those stations with phone letters beginning with "W" are located East of the Mississippi River, whilst those beginning with "K" happen to be West of it. Many stations put their private name which  (generally, but not always)  fits in with their call-letters. For instance, KDGE also calls itself "The Advantage", WFXF "The Fox" etc. KISS FM is an extremely popular name which sometimes, considering the station contact letters, is definitely bewildering! 

Gleam tendency for AM stations to drop the last "0" of their frequency - US stations use 10kHz channel spacing on AM and therefore their frequency will often end in "0". For instance, WABC 770kHz calls itself "77 WABC".