From a thread over on GLFWDA this is what "working CB" means;
Originally Posted by oz97tj
It should work from front of group to back in a reasonably sized group. With a group of 10 rigs, in a heavily wooded and hilly area, that is a good range for a tuned CB. They can sometimes do better, but a basic tuned set up should be able to get this distance fairly easily except when a big hill seperates the front and the back of the pack.
74 days to go!