The SRS Drawing Office collection of signal box diagrams has been built up over many years and comprises hand drawn sketches of the layout controlled by a signal box. Signals and point connections are numbered and the information included is that which would appear on the diagram displayed in the signal box itself. For some locations additional information such as locking charts, amendment state and so on is included. A full index of locations can be found in the 'Drawings' section of the main web site.
The locations on this USB Drive are those in Section B, the Bristol Division plus the Clifton Extension, Hotwells & Avonmouth, Avonmouth Dock, Andoversford, Tidworth joint lines.