A Transmitting Station (as it was termed by the Royal Navy; it was called a "Plotting Room" in American naval parlance) is a room deep within a large ship where communications and calculations pertaining to gunnery are worked. It serves as a nexus for command and communication.
The size and sophistication of a T.S. varied by the nationality, date of design and type of vessel. Generally, the later and larger ships of the most technologically advanced nations boasted the largest dimensions, headcount and machinery.