Why don't we use coax for cable? (1 Viewer)

[AgentGeekSquat]

If you can get HD with an antenna, why must everybody who wants to have cable have a cable box and connect with HDMI for HD?

I'm pretty sure if you unscrew the coax going to the cable box and throw it in the TV then you just won't get anything and if you use coax from the cable box it will look terrible. But why? Is it simply to prevent people from stealing cable and for you to pay for a cable box?

Why then do so many TV manufacturers insist on having that TV or "live TV" input on your input list? Most do not let you remove it.

 

[Al.Anderson]

I think it's what you surmised - so they can scramble the signal and de-scramble it in the set-top box. Most of the purpose of HDMI is to prevent you from tapping into the signal.
The "Live TV" would be for when you're using an antenna. Or do you have both "TV" and "Live TV" inputs?

 

[LeoA]

As far as I know, it's because of the differences between digital and analog. Coaxial has the bandwidth to deliver a compressed HD digital signal, but not an uncompressed HD analog signal.

And since televisions expect analog from their coaxial inputs, you need something in-between to handle the decompression.

 

[LoveHT]

Plus one to LeoA's post. It's a bandwidth issue. The digital compression allows the signal to encode better sound and picture.
Of course this is oversimplifying it a bit.

 

[Wes K]

The traditional coax "cable" used to transmit standard definition straight to your TV in analog form very easily. But everything is transmitted digitally because it can travel compressed (which makes HD take up less bandwidth) which has to be processed in the cable box (unfolds all the info that was packed tightly). The HDMI can handle HD uncompressed so that's what's used to go from your cable box to the TV. All of this is also because of existing infrastructure. Basically all of the developed areas were wired with analog coax technology decades ago

 

[DaveF]

If your cable provider distributes local channels in clear QAM, you can connect the coax cable directly to your tv and get HD television. I did this for a couple years paying for a so-called "lifeline" cable subscription.

Otherwise, the cable box is fundamentally about the cable company controlling your access to channels according to your subscription. Maybe you're no old enough, but there have been cable boxes for decades, long before digital distribution and hdmi.