PYE PTC 4000/4001 type Z “Tulip” microphone used with the Vessel Traffic Management System (2019-187) by the Port of London Authority to communicate with ships in the Thames. Made by Pye Ltd., Radio Works in Cambridge, 1960-1990.
The Pye microphone was used in conjunction with the VTS console (2019-187) to communicate with ships navigating the Thames. The VTS was introduced at the Port of London Authority in 1959, though this is a later iteration (exact date unknown). This later console would have been attached to radar and a visual display unit and would track ships all the way into central London.