HDTV tuner confusion

"jerry" wrote in message
...
I am trying to google the facts on hdtv tuners and need some
help with
clarifications. If I misstate something please let me know.

digital = hdtv = atsc all describe the same tuner.

If I am going to receive hdtv from a cable company I do not
need a hdtv
with a tuner at all (I can use a hd monitor) If I ever wanted
to receive
OTA hdtv I would have to buy an external clear QAM tuner. In
that case
there is zero benefit from buying an hdtv with a turner.

I have seen some specs for hdtvs that have tuners:
ntsc/atsc tuner with clear QAM
Is this one tuner with all 3 functions? What does ntsc add?
Isn't ntsc
for analog signals and will be eliminated in the near future?

I have seen some hdtvs that have pip. They will have to have
at least 2
atsc tuners.

So the bottom line is if I am going to use a cable tv company
I can buy a
hd monitor and have the cable box provide the hdtv and
standard tv
signal, or buy an hdtv with atsc tuner (in which case the
tuner is
superfluous). The hd dvd players will work equally well with
either.

Thanks for any clarification.

Jerry

One reason to consider a monitor vs. an HDTV may be increased
resolution. Presently 2660x1600 seems to be topped out at 30"
but that will grow, as will the resolution. HDTVs per se are
speced out at 1920x1080 or less. We'll surely see 4x that
resolution in the future, and high-res monitors have a different
objective to merely displaying HDTV.

Not having a tuner in an HDTV will probably not yield a cost
savings worthy of the search. In the past, it might have been
worthwhile, now it's more important to know your display
objectives and review the specs on how various manufactures have
implemented them.

All else being equal between an HDTV and a tunerless monitor,
what do you expect as a benefit from the latter?

"UCLAN" wrote in message
...
L Alpert wrote:

If you want to receive OTA, QAM is not needed. Most ATSC tuners
are QAM compatible these days, which is good if you subscribe to
cable without their box as so you can pick up HD stations that are
no scrambled (usually the locals), as QAM is the encoding
technology used by the cable companies.

QAM is *NOT* an encoding technology. QAM is a modulation technology
used
on ATSC signals by cable companies to increase bandwidth. OTA uses
8VSB
modulation of ATSC.

Some say potatoes, some say potatoes.

L Alpert wrote:

If you want to receive OTA, QAM is not needed. Most ATSC tuners
are QAM compatible these days, which is good if you subscribe to
cable without their box as so you can pick up HD stations that are
no scrambled (usually the locals), as QAM is the encoding
technology used by the cable companies.

QAM is *NOT* an encoding technology. QAM is a modulation technology
used
on ATSC signals by cable companies to increase bandwidth. OTA uses
8VSB
modulation of ATSC.

Some say potatoes, some say potatoes.

The difference between "encoding" and "modulating" technologies is *not*
simple pronunciation.

L Alpert wrote:
....

If you want to receive OTA, QAM is not needed.
TRUE.

Most ATSC tuners are
QAM compatible these days,

In practice a "tuner" may do Both ATSC and QAM.
HOWEVER, ATSC is for over the air, and QAM is for over the cable.

which is good if you subscribe to cable
without their box as so you can pick up HD stations that are no
scrambled (usually the locals), as QAM is the encoding technology used
by the cable companies.
....

UCLAN wrote:
sorry-spammers wrote:

"Clear QAM" is for *cable* reception. In most cases if your TV has a
QAM tuner you can get most free digital channels without a cable box,
but your channel numbers will probably be very wrong... and you
probably won't be getting premium channels like HBO.

To watch OTA DTV (high-definition or standard) you need an ATSC tuner.

Sigh...OTA uses 8VSB modulated ATSC; cable uses QAM modulated ATSC. But
they
are both ATSC.


The trouble is that the technical designation is not
the wordsmithing used by the marketing people. On a
product you should see the words ATSC and QAM to indicate
that the product works for over-the-air and for over-the-cable.

RickMerrill wrote:

In practice a "tuner" may do Both ATSC and QAM.
HOWEVER, ATSC is for over the air, and QAM is for over the cable.

ATSC is *both* over-the-air and cable. OTA is 8VSB modulated ATSC
and cable is QAM modulated ATSC.

RickMerrill wrote:

Sigh...OTA uses 8VSB modulated ATSC; cable uses QAM modulated ATSC.
But they
are both ATSC.

The trouble is that the technical designation is not
the wordsmithing used by the marketing people. On a
product you should see the words ATSC and QAM to indicate
that the product works for over-the-air and for over-the-cable.

*What* marketing people? I have seen numerous TV specifications that
correctly state that the tuner is: ATSC (8VSB/QAM), NTSC.

The ATSC specification mandates that the tuner demodulate 8VSB signals,
hence 8VSB is usually not mentioned in the tuner specifications. QAM
demodulation will likely be added in the next update, but is not currently
mandatory. So, some tuner specifications mention it as well.

Do "marketing people" decide what is right and what is wrong?

On Tue, 17 Mar 2009 11:41:16 -0700, UCLAN wrote:

*What* marketing people? I have seen numerous TV specifications that
correctly state that the tuner is: ATSC (8VSB/QAM), NTSC.

And I've seen *many* specs online that list them as ATSC/NTSC/QAM. or
other combos of the 3. And not all ATSC tuners do QAM. While technically
wrong, I think it's probably a good thing to separate them for the general
public.

--
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Wes Newell wrote:

*What* marketing people? I have seen numerous TV specifications that
correctly state that the tuner is: ATSC (8VSB/QAM), NTSC.

And I've seen *many* specs online that list them as ATSC/NTSC/QAM. or
other combos of the 3.

And I explained why in my previous post.

And not all ATSC tuners do QAM.

Never said they did. That's why QAM is mentioned in the spec. 8VSB need not
be mentioned in the tuner spec since it's part of the ATSC spec.

None of this changes the fact that both QAM and 8VSB are modulation methods
used for ATSC, and that QAM is *not* and encoding method. Saying that ATSC
is for over-the-air only is just plain WRONG.

On Wed, 18 Mar 2009 11:27:46 -0700, UCLAN wrote:

Wes Newell wrote:

*What* marketing people? I have seen numerous TV specifications that
correctly state that the tuner is: ATSC (8VSB/QAM), NTSC.

And I've seen *many* specs online that list them as ATSC/NTSC/QAM. or
other combos of the 3.

And I explained why in my previous post.

And not all ATSC tuners do QAM.

Never said they did. That's why QAM is mentioned in the spec. 8VSB need
not be mentioned in the tuner spec since it's part of the ATSC spec.

None of this changes the fact that both QAM and 8VSB are modulation
methods used for ATSC, and that QAM is *not* and encoding method. Saying
that ATSC is for over-the-air only is just plain WRONG.

I'm not disagreeing, just that some atsc tuners do not have qam capability
and being so I think it's best that they advertise it's capability
separately. AFAIK, all ATSC tuners do have 8VSB (OTA) capability.



--
Want the ultimate in free OTA SD/HDTV Recorder? http://mythtv.org
My Tivo Experience http://wesnewell.no-ip.com/tivo.htm
Tivo HD/S3 compared http://wesnewell.no-ip.com/mythtivo.htm
AMD cpu help http://wesnewell.no-ip.com/cpu.php