You keep mentioning side lobes, ack wash / back lobe, and main lobe signal. What are they?
A directional antenna is like a flashlight: it concentrates the shortwave radio signal in a very specific direction. This concentrated signal is the antenna’s main lobe and, being concentrated, is the station’s most powerful signal, guaranteeing the strongest possible reception. However, like all things, nothing is perfect, and directional antennas are no exception. Using our flashlight analogy, imagine that the flashlight reflector has a few holes poked in it. While the vast majority of the light is concentrated in one direction (the main lobe,) a very small amount of light escapes through these holes. These holes are called an antenna’s side lobes and back wash / back lobe signals. As for the difference between back wash / back lobe signals and side lobe signals, back wash / back lobe signals are in the opposite direction of the station’s main lobe signal, while side lobes come off the sides of the antenna. Neither back wash / back lobe or side lobes are powerful or reliable signals.
