Decca Roller Map Display

[Mike Watterson]

The map, as I understand it, was for fixed areas with the pointer that could include a pen to draw a trace of the route travelled.  Very popular wuth fishng trawlers who could lift the lid and and add an X where they had found good fishing on previous occasions.

This one looks too narrow for marine and doesn't look like it takes a pen.

I had assumed this was an aviation device, I se the Decca system was used for both ships and aircraft too. Getting an actual map would be great, or even seeing what one looked like. D

I think the marine models are much much wider. This one may be for a helicopter or plane on a regular route.