Let us remember this day. On this day in history, Dec. 12, 1901, Guglielmo Marconi sends first transatlantic radio message (msn.com)
https://forums.qrz.com/index.php?threads/1st-transatlantic-message-sent-101-years-ago-today.842262/ Also, Marconi didn't send it. He received it. He was not playing the mambo at the time, but he was listening to the radio.