The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources. “Radio Scouting — The Adventure of Youth Amateur Radio” is the theme for the 43rd edition of the international Amateur Radio exhibition, HAM RADIO, in . HAM RADIO - The International HAM Flea Market. Statements. Ham radio fans from all over the world will be coming together in Friedrichshafen for the 44th time.