'Real' Digital CATV

Discussion in 'Playback Devices' started by Glenn Overholt, Aug 19, 2003.

  1. Glenn Overholt

    Glenn Overholt Producer

    Mar 24, 1999
    Likes Received:
    I have some questions about this, so feel free to blast away at anything that I say. I have a feeling that some people think they are receiving digital cable, but are not.

    The 'top of the line' for this would be to have a cable box with a DVI(-D) output that feeds into an HDTV at 1080i. You would have a digital signal from start to finish.

    If the cable box only has component outputs (at best), is the digital HD signal in the cable box converted to analog before it goes to the component cables that go to the TV? This would be one step down from the 'top of the line', and still be 'HD', but not 100% digital.

    If you did not have an HDTV, (even if you do get a better picture with 'digital cable'), it would only be 480i at best. With that, using an S-video cable or even a composite cable wouldn't be as good as component, but close. (We can skip the discussion on comparing picture quality by moving up from composite to s-video, etc).

    Back to square one. I know how screwed up advertising can get, but any cable box that did not have a working dvi output can't legally state that a user can receive a digital signal on their TV. (Yes, I know that they have this worded to avoid lawsuits).

    So, could a digital cable box that only had component (at best) outputs really be a digital cable box? If that were true, could you demand the digital cable box at the price of an analog one because they didn't have the proper outputs? What if your only TV had one input - a DVI-D?

    (Advanced section, just for the sick & twisted!) Unscrew the back panel plate on your TV, where all of the sockets are. Carefully tape it inside, and then get a blank plate, cut out a slot for a DVI connector, and set it in place. If the cable installer didn't have a CATV box with a working DVI output with him, he'd be screwed!

    (Admins - I put this in TV because it does not refer to any specific piece of hardware, but rather, just the signal itself).

    So, in how many places did I screw up?

  2. Patrick Sun

    Patrick Sun Moderator

    Jun 30, 1999
    Likes Received:
    It is quite possible that for the delivery of HDTV signals to a HDTV-ready set, there are specs that require, as a minimum, component inputs, and that the firewire and DVI inputs are technological gravy for the next wave of HDTV. But to maintain some form of consistency, HDTV sets would have to always accept component video input signals for 720p/1080i in addition to any other HDTV input.

    So, given that premise, the CATV companies are covered in stating that the HDTV signal delivered is still a digital signal, not analog (no matter how much of a brouhaha is raised over the component video input delivery of the HDTV signal to the TV). The CATV HDTV box is doing the same that that any other OTA Digital HDTV STB/tuner, with component video output, does. So the CATV companies are delivering HDTV signals to the home via their own digital cable TV network bandwidth.

    Also, I think it would be rather a logistical nightmare to only concentrate on delivering a DVI HDTV signal to the home when HDTV sets when, as a minimum, component video input is the baseline for HDTV-ready sets.

    Now, with Digital CATV, it's digital because of the nature of the signal itself (1s and 0s), while analog cable channels are not. Again, I don't think you can expect the CATV companies to make their digital STB to accomodate DVI for standard HDTV fare delivered via CATV, or standard CATV fare either. The CATV digital STB are designed to output signals that the majority of their subscribers' TVs can handle, and as a baseline, that is not going to be DVI now. This is not to say it won't happen in the future after we get to 2006/2007, but you're just going to annoy a lot of CATV installers with that DVI-only TV set you rigged up... [​IMG]

    (and I'm moving this to A/V sources because this is not really a TV/HDTV programming topic).
  3. JeremyFr

    JeremyFr Supporting Actor

    Jan 28, 2003
    Likes Received:
    I've got a Motorola DCT 5100 that has a working DVI output and outputs everything scaled to 1080i or I can set it up for native 480p for the standard digital channel's and 1080i for the HD channels. So I guess the question is null[​IMG]
  4. Lew Crippen

    Lew Crippen Executive Producer

    May 19, 2002
    Likes Received:

Share This Page