Beyond their love of radio, amateur radio operators and shortwave radio broadcasters have one thing in common: They rely on the ionosphere to refract or bend their signals back to Earth, so that they can travel beyond line-of-sight distances.
In turn, the ionosphere’s ability to refract radio signals depends on its level of ionization or charge. The more ionized the ionosphere is, the more likely it is to bend signals back to the ground rather than let them pass through.
Here’s where the sun comes in. The number of sunspots on the solar surface rises and falls over an 11-year period, during what is known as a solar cycle. The more sunspots, the more solar radiation comes to Earth.
This radiation ionizes the ionosphere, improving the propagation of signals for transmitters and receivers alike.
Right now is a good time for amateur operators and shortwave broadcasters (and listeners), because the world is just coming off the peak, or solar maximum, of Solar Cycle 25.
Read more – RadioWorld: https://bit.ly/3Odzc1m
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