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Originally Posted by N9ZQA
The switch to digital only affects BROADCAST television. Cable companies are not required to switch to digital transmission, although some are taking advantage of the media hype over DTV to move in that direction.
I'm not sure what the regulations are regarding the use of the -DT suffix on a station's callsign.
"Digital cable" uses QAM modulation instead of 8VSB as ATSC does for over-the-air transmission. You are correct in that digital cable viewers require a set-top box to decode the digital signal to either RF, composite video, or some other form of display interface technology - the same as using the converter box to receive over-the-air broadcasts.
As I understand it, the analog feeds on the cable of the local channels are done with a slightly heavier-duty version of the set-top converter boxes we've come to know and love. There may be other methods, but I'm not aware of any at the moment. Would love to hear if anyone has further info.
However, since cable television is brought to you on - just that - a cable, there is no requirement for them to use either analog or digital. The signals transmitted down that cable do not exist to the outside world (at least on a good day), so the cable company can send digital signals as well as analog NTSC signals. The advantage to them is that they can pack multiple digital signals into the bandwidth occupied by 1 analog channel. These signals are all RF, just different types of modulation - much like 10M AM and FM - same frequency, same intrinsic information transmitted, but completely different modulation schemes.
-Jim
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I think you are missing my point. I am wondering how I can get my local channels without a converter box (my cable is connected more or less directly to my television--I say more or less because I have a VCR and a DVD player) if they are not standard television signals. This entire digital TV system has me baffled, and I don't know to this day what all the fuss was about (changing the date from 02.17 to 06.12 and all the other rigamarole that stood in the way of the thing, not to mention all the worrying the FCC did over people not being ready for the transition), as I cannot see the difference in the picture on my set.
The government should have left the old reliable NTSC system alone, as DTV, at least in its early stages, is proving to be more trouble than it is worth for a lot of viewers. I recently read in an e-mail newsletter from Broadcasting&Cable that the ABC television station in Philadelphia had to apply to the FCC for some sort of temporary permission to increase their signal so that it would "reach the fringes", whatever that means. (If viewers are having problems getting that channel or any other in digital, put up an antenna, as people used to do when color television arrived in this country in the 1960s and before there was such a thing as cable.)
I remember when "WDTV" was the call sign of a television station in West Virginia, and meant nothing more. Now, lop off the W and we have the abbreviation for a television standard that has all but turned television as we know it upside down. People are being all but forced to get cable because they can no longer get their area's local stations with an ordinary aerial, as they had been used to for over five decades. I still cannot get used to the idea that my own TV will not work without cable. I've had to downgrade my cable service to Time-Warner's basic level (local channels only) and really do miss being able to get my TV with an aerial. The FCC really blew it this time.
Over and out.