These solutions were generated from a single run of RepeaterBots.  Each robot starts in grid square (2, 2).

Note that in the solutions, Robot A explores, looking for the second beacon.  Robot B tends to linger at the bottom right of the grid until it can no longer hear the radio of Robot A (see maze 2). 

Because there is some refraction of radio waves around barrier edges, radio waves are not attenuated by the edge of barriers.