Re: Digital TV question? + more!
I wonder if you run the cable signal thru a digital tuner on a VCR/DVD combo if your analogue CRT TV will get all the channels?
I think you have some confusion here. You are confusling video and the RF (radio frequency) signal the comes down the cable line and off air broadcasters.
To carry a lot of video down the cable the video signal must be put on a carrier wave and that wave is modulated. In the analog world multiple carrier waves are combined to deliver multiple television channels.
That is different from the base band video. Your DVD or whatever selects one of the carrier waves and decodes it. You now have a single video.
What you would feed your older set is the video/audio.
The following is just some additional information in case you are interested:
Video can be analog or digital. The analog video, known in the US as NTSC (useless info here - stands for National Television Standard Committee) is analog video. Digital video is often referred to as 601 which is the ITU standard that defines it.
Analog broadcast or cable is done using the analog signals that are modulated by amplitude modulation (video) and frequency modulation (audio) and fits into a 6MHz channel.
The new DTV takes digital vdeo and modulates it with digital modulation. For example it can use Quadture Amplitude Modulation or QAM. You may have heard of QAM tuners.
Hope that helps.