Before the location even opened, NBC announced plans to build studios in the Mart. When opened on October 20, 1930, the nineteenth floor location covered and supported a variety of live broadcasts including those requiring orchestras. WENR and WMAQ broadcast from the location. Expanded in 1935, with office space in the previously unoccupied tower, the additional provided room for an organ chamber, two echo rooms, and a total of 11 studios. A staff of more than 300 produced up to 1,700 programs each month, including "Amos 'n' Andy".