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Comment by axiolite

7 months ago

"A terrestrial (over-the-air) transmission carries 19.39 megabits of data per second (a fluctuating bandwidth of about 18.3 Mbit/s left after overhead such as error correction, program guide, closed captioning, etc.),"

https://en.wikipedia.org/wiki/ATSC_standards#MPEG-2

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axiolite

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ValdikSS  7 months ago

But that's the whole multiplex, right?

It could be a single channel, but usually you have many in the multiplex. I don't know how it works in the US, but for DVB-T(2) that's how it is.

  • axiolite  7 months ago

    Circa 2009 when analog TV was first shut-off in the US, each DTV station usually only had one channel, or perhaps a second basic one like a static weather radar on-screen. Some did have 3 or 4 sub-channels early on, but it was uncommon.

    Circa 2019, after the FCC "repack" / "incentive auction" (to free-up TV channels for cellular LTE use) it became very common for each RF channel to carry 4+ channels. But to be fair, many broadcasters did purchase new, improved MPEG-2 encoders at that time, which do perform better with a lower bit-rate, so quality didn't degrade by a lot.