Can you hook HD Cable TV into HDtivo?

Discussion in 'DirecTV TiVo Powered PVRs & Receivers' started by Sean Cusick, May 25, 2005.

  1. Sean Cusick

    Sean Cusick New Member

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    Feb 28, 2002
    Boston, MA

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    I can get HD locals off of my cable modem line. I spliced it and found that I can get basic, as well as the HD locals. I don't feel like this is stealing, as wonderful Charter charges me an extra $10 for not having tv service with them. My question is: Can you hook cable up to your antenna input and get the HD thru it, like you would an off air antenna?

    Thanks.
     
  2. AbMagFab

    AbMagFab What happened, TiVo?

    3,638
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    Feb 5, 2001
    No.

    And how do you know you're getting HD locals from cable? Do you have a QAM capable TV? Which one?

    Or instead, are you just getting OTA reception from the physical cable, since it's acting like an antenna, and you tested through your ATSC capable TV? Much more likely.
     
  3. Sean Cusick

    Sean Cusick New Member

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    Feb 28, 2002
    Boston, MA
    I have a sony Grand Vega LCD. It will display the HD content from cable without a HD box. I was just wondering if I ran it into the hdtivo, would it treat the HD signals the same as an antenna.
     
  4. AbMagFab

    AbMagFab What happened, TiVo?

    3,638
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    Feb 5, 2001
    So do I. What model number? The newest one's I was aware of only had an ATSC tuner (OTA) and a cable-card tuner. Without the cable card, you can't view things like HD cable channels.

    So you're saying you installed and activated a cable card? Or is it possible you're viewing OTA channels, and it's just using the physical cable as an antenna?
     
  5. dt_dc

    dt_dc Mostly Harmless

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    Jul 31, 2003
    Northern...

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    Some people might call it "Passive Cable Theft".
    No.

    OTA uses 8VSB modulation. Your HDTivo has an 8VSB demodulator to recieve those signals.

    Digital cable (including HD channels) use QAM modulation. HDTivos do not have a QAM demodulator to recieve those signals.
     
  6. dt_dc

    dt_dc Mostly Harmless

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    Jul 31, 2003
    Northern...
    Without the CableCard you can view all unencrypted digital cable channels and all unscrambled analog channels.

    Via FCC regulations, HD locals are supposed to be carried unencrypted (and usually are) ... hence the ability to pick up HD locals w/o the CableCard (but not extended / encrypted HD channels like ESPN-HD, HBO-HD, etc.)
     
  7. AbMagFab

    AbMagFab What happened, TiVo?

    3,638
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    Feb 5, 2001
    You sure these TV's have a QAM tuner, outside of the cable card capabilities? Nothing in the specs.
     
  8. dt_dc

    dt_dc Mostly Harmless

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    Jul 31, 2003
    Northern...
    Every CableCard TV I've played with can get unencrypted QAM w/o a CableCard. This includes a Grand Wega (KDF-50WE655). Actually ... looking in the manual ...
    http://esupport.sony.com/perl/model-documents.pl?mdl=KDF50WE655

    It's certainly possible some TVs can't. You'd want to look into the details on a specific TV if this feature is important to you.

    However, a CableCard is just a crypto chip on a card. The QAM tuner / MPEG decoder and everything else required to get digital cable channels is all in the TV. The only thing the card does is unencrypt encrypted channels. If a manufacturer is making a CableCard TV, there is absolutely no extra costs or hardware or anything additional they need to do in order to get unencrypted QAM. Frankly, they all use the same SoC chipsets so a manufacturer would probably have to do additional work to DISABLE unencrypted QAM reception.
     
  9. MNTivoGuy

    MNTivoGuy New Member

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    Oct 21, 2002
    I don't get this. What do you plug the coax cable "out" into to get HD locals if not a cable box and than a digital out to component/DVI/HDMI.
     
  10. dt_dc

    dt_dc Mostly Harmless

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    Jul 31, 2003
    Northern...
    You plug the coax straight from the wall into the TV.

    If someone can make a "box" that takes the coax in ... and then feeds an HD signal to a TV via component/DVI/HDMI ... they can just as easily take everything in the "box" ... stick it in a TV ... and make a TV that can just take coax in and doesn't need the external "box" ...
     
  11. Sean Cusick

    Sean Cusick New Member

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    Feb 28, 2002
    Boston, MA
    On my Sony Grand Vega 55" I just hooked the cable into the uhf/vhf and like people are now stating, can pick up all of the local HD that charter has on. I do not have a cable card. I only wish that I had known this before putting a new anttena on the roof. But I guess from what people are stating, the tivo would not have picked them up, so I guess it is worth it. I guess at least I have a back up source of HD if I run into a off air problem.
     
  12. MNTivoGuy

    MNTivoGuy New Member

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    Oct 21, 2002
    Do I need a TV with an ASTC tuner to try this? Mine I think has an NSTC tuner (sony 34xbr910)
     
  13. feldon23

    feldon23 MythBuster

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    Mar 13, 2001
    Houston, TX
    When did that pass?

    HD locals are QAM in 99% of cable markets.
     
  14. dt_dc

    dt_dc Mostly Harmless

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    Northern...
    No ... to get the HD locals from your cable company you need a QAM tuner. Which, AFAIK the 34XBR910 does NOT have.

    With an NTSC tuner ... you'd just get any unscrambled analog channels your cable company sends.

    An "ATSC tuner" (aka, OTA digital) includes an 8VSB demodulator ... same as what the HDTivo uses to get OTA digital channels. See comments above. Cable companies don't (typically) use 8VSB. There used to be a very very few ... but they are all switching over to QAM.

    A "QAM tuner" lets you get unencrypted digital channels. There are a few TVs with QAM tuners ... also a few STBs (like the LST-3410A).

    A "Digital Cable Ready", "CableCard compatable" (whatever you want to call it) includes a QAM tuner so it can get digital cable channels. But it also allows you to use a card from your cable company to get encrypted digital channels.
     
  15. dt_dc

    dt_dc Mostly Harmless

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    Jul 31, 2003
    Northern...
    A long long time ago ...

    Basically, it's just an application of long-standing FCC regs:
    1) all OTA signals must be on 'basic tier'
    2) 'basic tier' may not be scrambled nor encrypted

    This was always the case with analog. The FCC didn't change things for digital. Several FCC orders and clarifications seem to confirm that the above applies to digital as well ...

    See the following post for exact references:
    http://www.tivocommunity.com/tivo-vb/showthread.php?p=2201139&&#post2201139
     
  16. whoodoggie

    whoodoggie New Member

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    Oct 1, 2003
    Much to my excitement,a couple of weeks ago my Sony 55WF655 did the same thing. Which is kinda nice, since I can't get CBS or PBS HD locals from DTV....but now I do! :)
     
  17. whoodoggie

    whoodoggie New Member

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    Oct 1, 2003
    ....although, the TV tuner sometimes registers those channels as 'No Signal', and I have to rescan the channels, or sometimes it just comes back on their own....anyone else have this problem?
     
  18. Pearhead

    Pearhead Zippity Do Da

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    Nov 26, 2005
    Not real sure how I stumbled across this thread but I'm glad I did. I bought a Sony KDF42WE655 about a year ago and set it up to use an OTA antenna for HD. A $20 Silver Sensor mounted to the back of my dish. Works great although my CBS station drops in an out occationally as it's right on the fringe of the directional sweet spot.

    I was just about to buy a multi-directional antenna to put that issue to bed when I found this bit of great info about the QAM tuner in my TV. I'm required to pay for basic cable for my internet connection but only use it for a deck TV. I was aware of the FCC reg regarding basic cable, but I never let the Sony search the cable spectrum since I was not aware that it applied to ALL OTA signals. Coo......I just saved about $40 bucks and don't have to venture back on the roof.

    In the ironic file is the OP was made on my birthday...so even though I didn't find this until now...I'm celebrating all over again. Cheers!

    Thanks for the happenstance heads up Sean.
     
  19. Pearhead

    Pearhead Zippity Do Da

    49
    3
    Nov 26, 2005
    When my TV scanned the cable, it found 149 digital channels...with 4 "shown" (networks). I assume the rest are scrambled or just not used currently. Odd deal is that some of the "sub channels" I recieve just fine OTA are "no signal" through the cable connection. No biggie as most of the current additional bandwith is only used for local weather/radar.

    As to your specific problem, yes I did notice some quirky behavior when setting up. Depending on what mode (favorites/PnP) I'm in, some channels mysteriously appear in my lineup. I went back an unchecked and so far alls been well. I think it has something to do with the Sony's limitation on PnPing HD signals in the right "window". It's logic gets scrambled....me thinks it's time for a patch. :cool:

    On a side note regarding the FCC deal. OTA.... our local PBS station has an HD feed with 5 subs. But for some reason they are not available via my cable connection. Their channel ID's show up in the scan, but they have "no signal". Maybe just an oversight by the cable company cause it looks like they've scrambled all the PBS stations.
     

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