Double-click to re-centre and zoom in.
Use scroll wheel to zoom in and out.
Click 'show boxes' to refresh display.
Use dashboard to see aerial view.
Grid references correspond to OS maps.
Map display by Virtual Earth.
Note: lat. and long. are shown in WGS84
coordinates. Signal boxes are positioned
using six figure grid references and they
will thus appear +100m/-20m S and/or W
from their intended position.