QST, January, 1921, page 48:
The DeForest company announces a nightly news service transmitted by radiophone from their station on the top of the World's Tower Building, New York, where one of their type OT-201 1 K.W. transmitters has been connected to an antenna running to the top of a four-story building at 49th and Broadway. An unusual feature is the location of the apparatus at the top of the antenna. The licensed wave length is 1650 meters.