Master Control was on the fourth floor in Grand Central... ST.41 was on the third floor. St.43, in the early days of TV, was a camera control studio for film. The camera had a pickup tube called an Iconoscope. Years later, a much better pickup tube was developed called a Vidicon. The control room for the Vidicon film cameras was on the second floor of Grand Central known as Vidicon Valley.
(After that, an EVEN better tube was developed called the Plumbicon, which was used in the Norelco PC70 cameras -- There were several other tubes as well, such as the Image Orthicon (IMO), the Saticon, and several experimental tubes as well, which were designed and constructed at CBS Labs in the '60's [ I was given one as a present, by the Lab's Chief glass blower, and if memory serves correctly, was Emil Torick] -- Dave M.)