rye9 said:
So then how would my picture look on this TV with analog cable?
Perhaps this would be a good time to review:
Analog Cable/TV (NTSC/480i)
This is what was simply known as "TV" until recently. Analog cable just added more channels than over the air by using the fact that in the cable there is less interference and more frequency bandwidth available than over the air. This works out of the box with a "cable ready" TV or may require a set-top box.
Digital Cable/DTV (480i/480p)
This is just a way that the cable operators can cram even more channels into the same wire, and force you to use a set-top-box or CableCard and can provide more individualized services like PPV and various premium packages. These channels are often compressed using MPEG2 and decoded in the STB to the same, plain 4801/NTSC signals by the time they get to your TV.
At this point the only difference between the two is the need for a decoder/cable box/cablecard and how the signals degrade. Analog signals get "snowy" digital gets "blocky" and may not keep up with fast moving action.
I oversimplify since 480p signals can also be sent over over the air DTV using ATSC, and set top boxes that have pregressive output could also output 480p from digital cable.
HDTV/HD Cable (720p/1080i)
Similar to DTV, except that it is higher resolution and can be decoded to 720p or 1080i and displayed as such on HDTVs/monitors. Over the air this uses ATSC, while on cable or satellite the signals would be compressed using MPEG-2 or MPEG-4 and decoded by a set-top-box or cablecard.
So,
unless you're talking HD, digital cable and analog cable will both look pretty much the same on an HDTV since they both are converted to a 480i signal. The 640x480 interlaced picture needs to be scaled up to the resolution of the HDTV, and you might be slightly more sensitve to the pixelation/blockiness of the MPEG compression of Digital Cable on an HDTV than on an analog TV or with Analog input due to the higher resolution of the HDTV. Since the 480i signal has a 4:3 aspect ratio, you will also have black bars on the sides of the picture, unless you scale the picture further up, potentially cropping or distorting the picture to make it fit the 16:9 screen.
B