Maybe longwave can make a come back with digital modulation. There's a ~100 kbit/s broadcast channel available way down there, with uniquely excellent propagation characteristics. (Viewing radio as a wave, at such long wavelengths, when the radio waves encounter buildings, or even mountain ranges, they diffract around them. It's like how most of the energy of a wave on the surface of some water diffracts around a small rock sticking out of the water, rather than being stopped by it.) A single transmitter can cover most of a continent, with indoor and even some ground penetration. Receivers are simple, and can have tiny antennas despite the wavelength. There are even watches that can sync themselves to longwave time signal broadcasts, which are about the only thing on LW currently broadcast in North America.