[mythtv-users] HD3000 and High-Def

[Zak]

Greg Woods wrote:

>On Thu, 2005-09-01 at 09:02 -0400, Brian Stults wrote:
>  
>
>>Donavan Stanley wrote:
>>    
>>
>
>  
>
>>>You don't USE a cable box with QAM.
>>>
>>>      
>>>
>>This really surprised me.  I bought an HD3000 a long time ago to get it
>>before the FCC deadline.  However, I haven't used it yet because I
>>thought I would need to get another cable box to use QAM.  So the tuner
>>in the HD3000 can receive channels in the hundreds?
>>    
>>
>
>What Donovan means (I think) is that cable companies do not generally
>provide HD over QAM. Yes, the HD3000 card will do QAM. But it's not a
>good card for that, because all the encoding is in software (which puts
>a high load on your CPU), and none of the content is HD. If you want to
>receive QAM signals, a PVR-150 or other MPEG2-encoder card is better.
>The HD3000 will receive HD OTA programming. If you want to get HD from
>your cable company, you will need a cable box that outputs unencrypted
>content over FireWire. From what I have read on this list, this is the
>only way to get HD content off of cable, and you will be fortunate if
>you can get a box like this from your local provider. Of course the
>people at the local office will have no clue what you're talking about
>if you ask them about any of this either. From what I've been able to
>gather, if I ever want to do real HD content, I will have to go to
>satellite or settle for what comes OTA.
>
>BTW, I too learned all this the hard way, after buying an HD3000 to beat
>the FCC deadline. Only then did I learn that it's not the right card for
>me. It worked with the QAM signal, but the PVR-150 works better and
>costs less. At some point, I may experiment with some antennas to try
>and get OTA HD using the HD3000. I've read here that you don't
>necessarily need a large rooftop antenna, people have done it with cheap
>$20 HD antennas from Radio Shack. Whether that will work for me (or for
>you) will depend on reception conditions in our respective areas, and
>whether our machines can handle the load of capturing and displaying an
>HD stream.
>
>--Greg
>
>
>
>  
>
>------------------------------------------------------------------------
>
>_______________________________________________
>mythtv-users mailing list
>mythtv-users at mythtv.org
>http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>  
>
With all due respect, this is pretty much wrong.  QAM is the method the 
cable companies use to carry signals to your house.  It has nothing to 
do with HD/SD.

The cable company can send either scrambled or unscrambled signals over 
QAM.  In order to receive the scrambled signals, you need a Cable box or 
a CableCard.  However, in order to receive the unscrambled QAM signals, 
you simply need a QAM-capable tuner.  That's where the HD3000 comes in.  
Most early ATSC (i.e., HD) tuners did not support QAM.  If you plugged 
in your cable line to the card, you would get nothing.  However, the 
newer cards let you capture QAM as well.  It will also let you record 
OTA programming if you use an antenna.  There is no "decoding" because 
the HD stream is already digital - the card simply saves it to the hard 
drive.

The PVR-150/250/350/500 will only let you receive SD.  Yes, they do QAM.