The American Radio Relay League (ARRL) hosted its annual Field Day over the June 28-29 weekend at the Concord Rod and Gun Club on Strawberry Hill Road, within handheld radio broadcasting distance from the Acton town line. Around 40,000 amateur radio operators, also known as “hams,” participate each year over the fourth weekend of June in the most popular on-the-air event in North America. The event has been running since 1933, interrupted only by World War II, and the operators who set up at the Concord site are members of the PART (Police Amateur Radio Team) of Westford club. According…