[YoungClayB]

My friend has digital cable through Time Warner...he just bought a new HDTV and has it hooked up directly to the raw coax. My question is this....how/why is he able to get HD channels? He is not recieving these HD channels over the air, they are really coming from the cable. How is this possible?

 

[Trek7300]



Quote:
Originally Posted by YoungClayB /forum/post/15410756


My friend has digital cable through Time Warner...he just bought a new HDTV and has it hooked up directly to the raw coax. My question is this....how/why is he able to get HD channels? He is not recieving these HD channels over the air, they are really coming from the cable. How is this possible?

Cable companies are required by law to pass local channels unencrypted to their customers - meaning no set top box should be required - as long as the TV set has a QAM tuner. Most sets sold now do have a QAM tuner. So, if the local channel is broadcasting in HD (as most major stations are doing now) then you will get some HD programming from the "raw" cable.


However, many of the premium HD channels, WILL require a set top box, and usually the cable company will require you to pay more money to subscribe to the extra HD channels.

 

[egnlsn]



Quote:
Originally Posted by YoungClayB /forum/post/15410756


My friend has digital cable through Time Warner...he just bought a new HDTV and has it hooked up directly to the raw coax. My question is this....how/why is he able to get HD channels? He is not recieving these HD channels over the air, they are really coming from the cable. How is this possible?

Raw coax? Sure it isn't medium well?

The ONLY difference between a TV set with a QAM tuner (his new HDTV set) and a digital cable box (QAM tuner) is the digital cable box can be authorized to receive encrypted channels. There might be a few other bells and whistles, but as far as tuning in digitally modulated cable channels, there is no difference.


Many cable systems transmit local channels in the clear, meaning that any old QAM tuner can receive and display them.

 

[HDMI Guy]



Quote:
Originally Posted by YoungClayB /forum/post/15410756


My friend has digital cable through Time Warner...he just bought a new HDTV and has it hooked up directly to the raw coax. My question is this....how/why is he able to get HD channels? He is not recieving these HD channels over the air, they are really coming from the cable. How is this possible?

Time Warner will have the local network channels available in HD over the cable. However in order to receive other channels such as Discovery, ESPN, etc... you need a cable box.

 

[smpowell]



Quote:
Originally Posted by YoungClayB /forum/post/15410756


My friend has digital cable through Time Warner...he just bought a new HDTV and has it hooked up directly to the raw coax. My question is this....how/why is he able to get HD channels? He is not recieving these HD channels over the air, they are really coming from the cable. How is this possible?

It's possible because as far as the coax cable is concerned, analog and digital TV signals are the same thing. If you look at someone's outdoor antenna, you will almost always find that there is the same old familiar coax cable connecting the antenna to their HDTV. Even "rabbit ear" antennas use coax to connect to HDTV's.


The difference between analog and digital TV signals isn't in how they are transmitted over the air or through cable; the difference is in the type of information that is modulated on the RF signal. That's why (in North America) you can use old TV antennas to receive digital broadcasts.


Now you may wonder, how come you can't use coax cable to connect your Blu-Ray player to your HDTV? The reason is that the equipment to encode/modulate digital TV video is way more expensive than that needed to modulate analog TV video.


Plus the digital rights management people would probably have conniptions.

 

[bill-tb]

Think of it same as cable providing Internet, with a cable modem, only it's digital TV signals that are being provided as a QAM signal to a receive only 'QAM modem'. QAM is just basically the same digital ATSC(8VSB) signal, but the QAM signal is more efficient, and requires a "cleaner noise environment" hence it's a cable only scheme. So QAM is not really a 'normal tuner' but more like a cable modem built-in to your TV. You may find you need to boost the cable signal for best QAM reception, especially if your house has multiple TVs running off a single main splitter.


When the signals are on the cable, or off the air, they are all analog. Digital is what does the modulating, not the transmitting. Since the demodulated signal is digital, it can be retransmitted with different schemes and be for the most part 'loss less' if desired. But compression is what cablecos do in order to increase their ability to carry more on their cables, and they are often lossy schemes. Your mileage may vary significantly when it comes to picture quality at the end user's site, depending......


Sometimes trying to simplify doesn't work right either ... YMMV

 

[txrose]



Quote:
Originally Posted by YoungClayB /forum/post/15410756


My friend has digital cable through Time Warner...he just bought a new HDTV and has it hooked up directly to the raw coax. My question is this....how/why is he able to get HD channels? He is not recieving these HD channels over the air, they are really coming from the cable. How is this possible?

Another explanation approach. If your friend had gotten an HD settop box from TW it would have provided an HD signal to his TV over HDMI or Component outputs. The box would have been connected to the coax. Everything but the descrambler in the box is in his TV from the QAM tuner to the MPEG decoder so that he can see any digital HD or SD signal which is not scrambled. Sets with Cable Cards built-in also include the descrambler and therefore can view all the HD and digital SD signals which do not require upstream data communication. But thats another thread.

I know this is redundant to the excellent posts others have made and is not intended to disagree with any of them.