On Mon, 20 Jan 2003 09:58:05 -0500, "Jim" wrote:

1 st what kind of tuner did you order? one for off air or Direct TV HD
No such thing as HDTV or none HDTV dish, they point at sat that has it or
not.

sorry, but to get HDTV channels, it requires a slightly differant
dish, one that has dual LNBs and is slightly wider. You have to pick
up dual feeds in order to get the double-bandwidth HDTV provides.


To get all direct tv chs, both hd and normal you need signal from 3 sats.
and a direct tv hdtv rec.
To get off air DTV you need uhf ant and maybe vhf ant.
It is possible to run all this on same coax, but all dishes and ants must
hooked up with special switches.
You need to check with complex on what setup they have.
"TJ" wrote in message
news:hcRW9.16457$ho2.7921@FE09...
I stay in a loft complex in Atlanta and just ordered an HDTV tuner for my
Hitachi. Knowing that I need some time of antenna, I went to our roof (3
stories and we have roof access - I can SEE every single tower in Atlanta)
and noticed that we have 3 already up there! The complex provides the DTV
dishes (which are scattered all over the roof - but are non HDTV) and it
seems as if they combine the UHF/DTV signals and feed them to the loft
apartments.

Is this possible? Is it possible for me to feed UHF/VHF and DTV signals
through the same coaxial cable?

Thanks.

Tony

"Isaac Wingfield" wrote in message
...
In article ,
(G.T.W.) wrote:

On Mon, 20 Jan 2003 09:58:05 -0500, "Jim" wrote:

1 st what kind of tuner did you order? one for off air or Direct TV HD
No such thing as HDTV or none HDTV dish, they point at sat that has it
or
not.

sorry, but to get HDTV channels, it requires a slightly differant
dish, one that has dual LNBs and is slightly wider. You have to pick
up dual feeds in order to get the double-bandwidth HDTV provides.

I don't think so.. One HDTV signal is about 16-18 MBits/sec. A single
DirecTV QPSK stream can provide more than that (about 20 or about 27
MBits/sec. depending on which data rate they're using). I suspect the
HDTV signals are coming from a different satellite (at a different
location) from the cluster that provides the normal TV signals. The
DirectTV system was designed *from the start* to be able to handle HDTV.

Isaac

D* HD channels are coming from the 110 and 119 orbital positions while most
of the standard programming is from 101. A 3 LNB dish oval is needed for HD
reception. They've been having a heck of a time getting 2 decent quality HD
channels on one transponder.

Pat

In article ,
"Pat Beal" wrote:

"Isaac Wingfield" wrote in message
...
In article ,
(G.T.W.) wrote:

On Mon, 20 Jan 2003 09:58:05 -0500, "Jim" wrote:

1 st what kind of tuner did you order? one for off air or Direct TV HD
No such thing as HDTV or none HDTV dish, they point at sat that has it
or
not.

sorry, but to get HDTV channels, it requires a slightly differant
dish, one that has dual LNBs and is slightly wider. You have to pick
up dual feeds in order to get the double-bandwidth HDTV provides.

I don't think so.. One HDTV signal is about 16-18 MBits/sec. A single
DirecTV QPSK stream can provide more than that (about 20 or about 27
MBits/sec. depending on which data rate they're using). I suspect the
HDTV signals are coming from a different satellite (at a different
location) from the cluster that provides the normal TV signals. The
DirectTV system was designed *from the start* to be able to handle HDTV.

Isaac

D* HD channels are coming from the 110 and 119 orbital positions while most
of the standard programming is from 101. A 3 LNB dish oval is needed for HD
reception. They've been having a heck of a time getting 2 decent quality HD
channels on one transponder.

For a given receiver antenna (dish) size, there is a tradeoff between
transmit power and bitrate. The way the birds are set up (at least the
first-generation ones), there are 64 transmit tubes (TWTs), and they can
be configured for 64 downlink "channels", or paralleled x2 for 32 with
twice the power. Before the system went live, there was some uncertainty
concerning how much power it would take to provide coverage to all of
CONUS, so they wanted some flexibility.

Also, the downlinks can be run at one of two bitrates (about 20 and
about 27 MBits/sec. payload). Combined with the possible paralleling of
TWTs, there are a number of ways they could set things up.

20 MBits/sec is more than enough for one HD signal, but nowhere near
enough for two. 27 MBits/sec. could handle two, but with only 14
MBits/sec per video + audio, it's no wonder things are a little bit less
than optimum. BTW, the audio takes up probably 256 KBits/sec, but
certainly no more than 384 KBits.

Isaac