The year 1941 saw a number of significant happenings in radio broadcasting history. Events 1 January – Federal Communications Commission approval of commercial FM radio in the United States takes effect. 29 March – 80 percent of North America's AM broadcasting frequencies are reassigned to new channels pursuant to the North American Regional Broadcasting Agreement. 27 May – Fireside chat by the President of the United States: Announcing Unlimited National Emergency (longest fireside chat). 22 June – The invasion of the Soviet Union by Nazi Germany is reported on Radio Moscow by Yuri Levitan (who in the autumn is evacuated to Sverdlovsk). 28 June – The first of four broadcasts from Berlin to the United States by English humorist P. G. Wodehouse, interned in Nazi Germany, is made. The series, entitled How to be an Internee Without Previous Training and comprising anecdotes about Wodehouse's experiences as a civilian internee, including some gentle mocking of his captors, are in August broadcast to the United Kingdom by the German propaganda ministry. 3 July – Soviet premier Joseph Stalin makes his first radio broadcast to his people following the invasion of their country. 6 August – C. S. Lewis begins a series of BBC Radio broadcasts that will be adapted as Mere Christianity. 11 September – Fireside chat: On Maintaining Freedom of the Seas following the Greer Incident. 21 November – The live blues radio program King Biscuit Time is broadcast for the first time on KFFA in Helena, Arkansas; it will attain its 17,000th broadcast in 2014 making it the longest-running daily American radio broadcast. 7 December – At 2:26 p.m. EST (19:26 GMT), the Mutual Broadcasting System interrupts its play-by-play commentary on the New York Giants/Brooklyn Dodgers NFL game to announce the attack on Pearl Harbor. At around the same time, NBC Red breaks into Sammy Kaye's musical program, NBC Blue suspends National Vespers, and CBS Radio interrupts a concert by the New York Philharmonic for an announcement made by John Charles Daly. 8 December – The President of the United States, Franklin D. Roosevelt, delivers the Presidential Address to Congress of 8 December 1941, commonly referred to as the "Infamy Speech" to a Joint Session of Congress at 12:30 p.m. EST (17:30 GMT). Transmitted live over all four major American radio networks, it attracts the largest audience ever measured for an American radio broadcast, with over 81 percent of homes