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Has anyone here ever wondered why most television broadcasts in the world are distributed by radio waves, and originally all television broadcasts were?
If you think about it's as follows; Unlike radio, television (actually the latter was called radio with pictures when it was developed) is not a very mobile medium, television viewership tending to be in a fixed position. Furthermore, the bandwidth of a video signal, let alone the complete audio-visual transmission, is much wider than an audio-only broadcast.

Cable broadcasting has advantages in terms of both bandwidth (and thus image resolution) and channel choice. Another advantage, that is for independent broadcasters, is it enables control of who may receive subscriber supported channels.

Let's consider the advantages in detail:

Image quality:

Throughout the analog era (before the advent of the compact disc (digital audio)) television never had more that 525 lines anywhere in any 60Hz countries, and rarely more than 625 in 50Hz countries. And it was interlaced, with only 480 active lines (others either being horizontal blanking intervals or in the vertical blanking interval) or 576 of them (in 60Hz countries). So the resolution was roughly equivalent to 16mm film. But 1000+ lines, especially with progressive scanning, could have offered resolution equivalent to 35mm film, and actually better image quality than 35mm film.

Channel choice:

Cable broadcasting doesn't propagate in all directions the way a radio transmission does.
When sound is broadcast over the air, different radio stations need different frequencies and the difference in frequency between any two radio transmissions has to be greater than the audio bandwidth. With terrestrial television, each channel needs two different frequencies to transmit the visual and audio part, and a guard band is needed between them.
With cable television, the picture and sound might be broadcast in different cables, in which case the same frequency could be used for both, increasing the bandwidth available. There might even be different pairs of cables for different channel packages, further increasing bandwidth.

In a country where the public broadcaster has a monopoly, it is possible to control which households can receive the public broadcasts simply through control of equipment. Specifically, anyone using equipment containing a television tuner needs to buy a licence from the public broadcaster. This doesn't work in a country with multiple independent broadcasters such as the U.S.A.
Cable broadcasting makes it easy for (subscriber supported) independent broadcasters to control access to their material. So they could charge a subscription fee and limit advertising to gaps between programs.

Note: Cable broadcasting means fully cable based, not using cables to help receive free-to-air in adverse areas like here.

So suppose that independent television stations broadcast by cable right from the beginning of television with the public broadcasters having a monopoly over non-cable terrestrial television.
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