To me this is extremely unusual. The jaged line represents the maximum distance the Radar Box can receive from my home. We are located at the edge of a valley with taller mountains on three sides. As you can see the reception South is good. What is unusual are the spikes going West and East seemingly going over the "home" on the screen. I observed no aircraft and the Radar Box log had no unusual flights. The only way for the spikes to appear is for the aircraft to have been at an extreme altitude.