[mythtv-users] Standard cable, QAM, PCHDTV-3000 vs Air2PC

[Steve Adeff]

On Sunday 13 November 2005 18:30, Daniel Kristjansson wrote:
> On Sun, 2005-11-13 at 17:00 -0500, Dale Pontius wrote:
> > So, the perennial question:  PCHDTV-3000 or Air2PC
> > The PCHDTV-3000 has built-in NTSC, which saves me a little money, but
> > not that much.
>
> While it is built in, currently with MythTV you can only use the card
> as either a HDTV or a NTSC card, but not both.
>
> > From what I understand, the newest rev of the Air2PC (with a new name)
> > has a better tuner, but I'm not sure that's important for cable.
>
> I don't know about the Air2PC HD-5000, but the pcHDTV HD-3000 has a
> better tuner for QAM than the old Air2PC.

the better tuner will only help with weak OTA signals, if the signal is strong 
then it won't matter as its all digital, a strong signal means your getting a 
low error rate copy of the stream, a better tuner won't really help beyond a 
certain point.

>
> > I'm likely to stay with cable, since my stations are in multiple
> > directions and my wife has already registered her disdain for a rotor.
>
> Depending on your distance from the stations a omni-directional antenna
> might work, and since UHF antennas are pretty small (mine is 1 ft long),
> you might be able to put up an antenna for each direction.

If your cable company broadcasts all your local OTA HD stations through their 
lines unencrypted, that would be the best way to go, no worries about 
antennas, you always get a strong signal etc.


> > When I hear about cable, I hear about QAM.  Why is a cable HTDV signal
> > different from over-the-air?
>
> The licenses for the 16-VSB patents are/were more expensive, and many
> cable operators were already using QAM-64 and QAM-256 for non-HDTV DTV
> by the time they started looking at HDTV. AOL-Time-Warner in New York
> was using VSB for a while, but I believe they have switched over to QAM
> now.
>
> > I've heard reports of both cards doing QAM, though the PCHDTV seems to
> > claim not to do it.  What gives?
>
> The pcHDTV HD-3000 supports QAM. The HD-2000 hardware supported it, but
> my understanding is that the pcHDTV folks could not get licensed QAM
> firmware for the HD-2000 from the DSP chip maker.

they just haven't updated their webpage, the HD-3000 definitely does QAM out 
of the box, I think they're just lazy web admins and over active computer 
engineers...

Steve