A long article so I won't quote it all here.During the American solar eclipses of October 2023 and April 2024, hundreds of radio amateurs will take to the airwaves. Their goal is to help scientists investigate what happens to radio signals when the Moon blocks the Sun.
TL:DR -- Radio waves bounce off the ionosphere, which is 50-400miles up, and then bounce off the ground and back up, allowing it to travel further. Solar rays trigger changes in the ionosphere, thickening it during daylight, and then it thins out at night, which means radio waves travel further at night because the ionosphere is higher up and the 'bounce' is bigger. (Which is why you could catch radio from Mexico and other distant places late at night). However, we still don't really understand what's going on within the Ionosphere.
With two Eclipses happening within a short time, HAM Radio operators are going to be filling the air waves and recording what they're able to transmit and receive, in order to learn more about the Sun's effects on the Ionosphere.