Are all digital tuners slow?
 

wrote in message
...
On Sun, 2 Sep 2007 15:59:15 -0700 Bill's News
wrote:

| I don't know about Comcast, but recent Adelphia/TW "boxes" only
| monitor the digital stream. If you've an analog device attached
| to their "box" it converts D2A.
|
| The analog stream is, of course, available to analog tuners
| which do not have a "box" between them and the cable.
|
| Of course if your box is quite old, then it may indeed be an
| analog only box.

It has to be a dual digital/analog box because it gets the local access
channels which are not yet on digital, and it gets channels that are on
digital only.

Their next generation boxes might well be digital only. They have said
new boxes are coming soon. If so, they will need to get the content of
the remaining analog only channels onto digital.

Comcast New Jersey has had Motorola digital only boxes available for at
least a year. As far as I can tell, there are no analog only channels. I
think the analog signals transmitted are all derived from digital feeds.

Tam

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below
|
| first name lower case at ipal.net /
|
|------------------------------------/-------------------------------------|

Are all digital tuners slow?
 

On Sun, 2 Sep 2007 20:54:02 -0400 Tam/WB2TT wrote:
|
| wrote in message
| ...
| On Sun, 2 Sep 2007 15:59:15 -0700 Bill's News
| wrote:
|
| | I don't know about Comcast, but recent Adelphia/TW "boxes" only
| | monitor the digital stream. If you've an analog device attached
| | to their "box" it converts D2A.
| |
| | The analog stream is, of course, available to analog tuners
| | which do not have a "box" between them and the cable.
| |
| | Of course if your box is quite old, then it may indeed be an
| | analog only box.
|
| It has to be a dual digital/analog box because it gets the local access
| channels which are not yet on digital, and it gets channels that are on
| digital only.
|
| Their next generation boxes might well be digital only. They have said
| new boxes are coming soon. If so, they will need to get the content of
| the remaining analog only channels onto digital.
|
| Comcast New Jersey has had Motorola digital only boxes available for at
| least a year. As far as I can tell, there are no analog only channels. I
| think the analog signals transmitted are all derived from digital feeds.

Maybe those are the boxes we'll be getting as soon as they finish their
head-end upgrades. The 3 local access channels I do know are fed to them
in NTSC analog. They will have to convert them to digital ... but that's
not hard for a cable company, in theory. They're just cheap and probably
will hold out as long as they can.

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / |
|------------------------------------/-------------------------------------|

Are all digital tuners slow?
 

wrote:
On Sun, 2 Sep 2007 02:48:25 -0400 Mark A wrote:

| There is a difference among TV brands (with respect to tuner delay) even
| among analog TV's. One thing that makes it take longer to tune in is if you
| have your cable box set to display the native mode (which takes longer to
| recognize for each channel) instead of always upscaling to the a fixed
| resolution of your TV set (usually the maximum resolution that your TV will
| display).

The actual frequency change can lock up in just milliseconds. Syncronizing
to the bit stream could take a little longer, but still just a fraction of
the time of one frame. Recognizing the actual video could could well take
a whole frame of time. That might account for 50ms to 80ms of time. The
rest is some combination of poor software programming and cheap slow CPUs
to run that software.


Wrong again. Take a look at the MPEG spec and you will see why.

Matthew

--
I'm a consultant. If you want an opinion I'll sell you one.
Which one do you want?

--
Posted via a free Usenet account from http://www.teranews.com

Are all digital tuners slow?
 

On Sep 2, 7:56 pm, wrote:
On Sun, 2 Sep 2007 20:54:02 -0400 Tam/WB2TT wrote:
|| wrote in message

...
| On Sun, 2 Sep 2007 15:59:15 -0700 Bill's News | wrote:

|
| | I don't know about Comcast, but recent Adelphia/TW "boxes" only
| | monitor the digital stream. If you've an analog device attached
| | to their "box" it converts D2A.
| |
| | The analog stream is, of course, available to analog tuners
| | which do not have a "box" between them and the cable.
| |
| | Of course if your box is quite old, then it may indeed be an
| | analog only box.
|
| It has to be a dual digital/analog box because it gets the local access
| channels which are not yet on digital, and it gets channels that are on
| digital only.
|
| Their next generation boxes might well be digital only. They have said
| new boxes are coming soon. If so, they will need to get the content of
| the remaining analog only channels onto digital.
|
| Comcast New Jersey has had Motorola digital only boxes available for at
| least a year. As far as I can tell, there are no analog only channels. I
| think the analog signals transmitted are all derived from digital feeds.

Maybe those are the boxes we'll be getting as soon as they finish their
head-end upgrades. The 3 local access channels I do know are fed to them
in NTSC analog. They will have to convert them to digital ... but that's
not hard for a cable company, in theory. They're just cheap and probably
will hold out as long as they can.

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / |
|------------------------------------/-------------------------------------|

Actually, the digital only boxes are cheaper than the analog/digital
ones. Headend equipment, while somewhat expensive, will be bought
anyway since it is just an incremental add on to the existing digital
cable systems in place. The big problem is that it tends to waste
bandwidth with simulcasting the same stuff twice (or 3X counting HD
feeds).

Are all digital tuners slow?
 

"Mark A" wrote in message
...
"Cathode Ray" wrote in message
er.mixmin.net...
I recently had my first experience with digital tv by buying an
inexpensive
RCA CRT television 20F514TD that had an ATSC/QAM tuner. One thing
noticed
was how slow the channels were to display after changing a channel.
There
was a 4-5 second delay between changing a channel and the channel
actually
being displayed. This was all on cable, not OTA. A friend mentioned
that
the delay sure killed the channel surfing experience.

My question is, is the delay in changing channels present in all digital
tuners or do more expensive televisions have better tuners with a
shorter
delay?

I eventually returned the RCA to Walmart as there were other problems
with
how the picture displayed. While analog channels looked ok, the digital
channels had odd color issues, mostly with tint. The fleshtones took on
a
very greenish color on certain scenes. Adjusting the tint control
didn't
really correct anything. It's almost like if there was a lot of green
in
the picture, everything would be green, including people's hair and skin
color. While the analog side looked ok, the digital channels were
overall
very dark. Turning up the brightness and contrast improved things
somewhat, but there still seemed like a great loss of detail in darker
areas of the screen. Messed with it for a few days, but the more I saw
the
less I liked. Packed it all back in the box very well, took it back to
the
store, just told them I didn't like the tv. That was it, received a
complete refund.

There is a difference among TV brands (with respect to tuner delay) even
among analog TV's. One thing that makes it take longer to tune in is if
you
have your cable box set to display the native mode (which takes longer to
recognize for each channel) instead of always upscaling to the a fixed
resolution of your TV set (usually the maximum resolution that your TV
will
display).


They don't have to be that way. I have read reports that Olevia HDTV channel
tuning by remote control can be as fast as old analog TV after a firmware
update thru RS232 port. I think in the beginning, many manufactures did it
wrong but now they have corrected themselves.

Are all digital tuners slow?
 

On Mon, 03 Sep 2007 19:54:04 -0000 Eric wrote:

| Actually, the digital only boxes are cheaper than the analog/digital
| ones. Headend equipment, while somewhat expensive, will be bought
| anyway since it is just an incremental add on to the existing digital
| cable systems in place. The big problem is that it tends to waste
| bandwidth with simulcasting the same stuff twice (or 3X counting HD
| feeds).

Ultimately cable systems will be moving to all-digital. They just don't
have the cash on hand to do it all overnight. They have to plan it based
on continuing revenue streams.

But I am puzzled why a cable system would duplicate an HD program 3 ways,
analog, SD digital, and HD digital. Are they using digital boxes that
cannot convert HD down to SD for output? That certainly would not be the
future direction to go.

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / |
|------------------------------------/-------------------------------------|

Are all digital tuners slow?
 

Mark A wrote:
"Cathode Ray" wrote in message
er.mixmin.net...
I recently had my first experience with digital tv by buying an inexpensive
RCA CRT television 20F514TD that had an ATSC/QAM tuner. One thing noticed
was how slow the channels were to display after changing a channel. There
was a 4-5 second delay between changing a channel and the channel actually
being displayed. This was all on cable, not OTA. A friend mentioned that
the delay sure killed the channel surfing experience.

My question is, is the delay in changing channels present in all digital
tuners or do more expensive televisions have better tuners with a shorter
delay?

I eventually returned the RCA to Walmart as there were other problems with
how the picture displayed. While analog channels looked ok, the digital
channels had odd color issues, mostly with tint. The fleshtones took on a
very greenish color on certain scenes. Adjusting the tint control didn't
really correct anything. It's almost like if there was a lot of green in
the picture, everything would be green, including people's hair and skin
color. While the analog side looked ok, the digital channels were overall
very dark. Turning up the brightness and contrast improved things
somewhat, but there still seemed like a great loss of detail in darker
areas of the screen. Messed with it for a few days, but the more I saw
the
less I liked. Packed it all back in the box very well, took it back to
the
store, just told them I didn't like the tv. That was it, received a
complete refund.

There is a difference among TV brands (with respect to tuner delay) even
among analog TV's. One thing that makes it take longer to tune in is if you
have your cable box set to display the native mode (which takes longer to
recognize for each channel) instead of always upscaling to the a fixed
resolution of your TV set (usually the maximum resolution that your TV will
display).


Two year old Samsung, OTA San Diego.

We also see differences from station to
station. The local PBS and NBC outlets seem
to synch quickest -- they both run a primary
channel and an SD/480 subchannel.

The Fox outlet is the most unpredictable
(transmitter is in Mexico) and sometimes it
takes 20-30 seconds for the tuner to report
"No A/V."

CBS, ABC and independent outlets fall
somewhere in between. And, as others have
noted, picture resolution (480 or 720) makes
a difference in "tuner agility."

My impression -- channel surfing is giving
away to using a program guide.

I really miss my old Picture-in-Picture from
the analog days.

--
pete

Are all digital tuners slow?
 

wrote in message
...
On Mon, 03 Sep 2007 19:54:04 -0000 Eric wrote:

| Actually, the digital only boxes are cheaper than the analog/digital
| ones. Headend equipment, while somewhat expensive, will be bought
| anyway since it is just an incremental add on to the existing digital
| cable systems in place. The big problem is that it tends to waste
| bandwidth with simulcasting the same stuff twice (or 3X counting HD
| feeds).

Ultimately cable systems will be moving to all-digital. They just don't
have the cash on hand to do it all overnight. They have to plan it based
on continuing revenue streams.

But I am puzzled why a cable system would duplicate an HD program 3 ways,
analog, SD digital, and HD digital. Are they using digital boxes that
cannot convert HD down to SD for output? That certainly would not be the
future direction to go.

More than likely for people who have no cable box; or maybe a box on one
set, and 4 other TVs and VCRs with none. I have a DVR on the HD set, and no
boxes on two other sets. I think this is common.

Tam

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below
|
| first name lower case at ipal.net /
|
|------------------------------------/-------------------------------------|

Are all digital tuners slow?
 

On Mon, 03 Sep 2007 13:38:10 -0400 Matthew L. Martin wrote:
| wrote:
| On Sun, 2 Sep 2007 02:48:25 -0400 Mark A wrote:
|
| | There is a difference among TV brands (with respect to tuner delay) even
| | among analog TV's. One thing that makes it take longer to tune in is if you
| | have your cable box set to display the native mode (which takes longer to
| | recognize for each channel) instead of always upscaling to the a fixed
| | resolution of your TV set (usually the maximum resolution that your TV will
| | display).
|
| The actual frequency change can lock up in just milliseconds. Syncronizing
| to the bit stream could take a little longer, but still just a fraction of
| the time of one frame. Recognizing the actual video could could well take
| a whole frame of time. That might account for 50ms to 80ms of time. The
| rest is some combination of poor software programming and cheap slow CPUs
| to run that software.
|
|
| Wrong again. Take a look at the MPEG spec and you will see why.

Take a look at the ATSC spec.

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / |
|------------------------------------/-------------------------------------|

Are all digital tuners slow?
 

On Sep 4, 7:29 am, wrote:
On Mon, 03 Sep 2007 19:54:04 -0000 Eric wrote:

| Actually, the digital only boxes are cheaper than the analog/digital
| ones. Headend equipment, while somewhat expensive, will be bought
| anyway since it is just an incremental add on to the existing digital
| cable systems in place. The big problem is that it tends to waste
| bandwidth with simulcasting the same stuff twice (or 3X counting HD
| feeds).

Ultimately cable systems will be moving to all-digital. They just don't
have the cash on hand to do it all overnight. They have to plan it based
on continuing revenue streams.

But I am puzzled why a cable system would duplicate an HD program 3 ways,
analog, SD digital, and HD digital. Are they using digital boxes that
cannot convert HD down to SD for output? That certainly would not be the
future direction to go.


Yes, that's right. The older gen Moto boxes won't display anything if
you tune to an HD channel (IIRC they do have the sound). There are
still a ton of TVs out there without set top boxes on them, so the
analog feed still needs to be sent down the line, and if you want to
use the cheaper set tops (without an analog tuner), you need to
simulcast the SD feed over digital. The bonus is that if you have an
older gen moto, you will get the all digital feed automatically,
theoretically improving your picture quality. We are talking about
millions of set tops here. Even a small cable system, say 10,000
subscribers, will have to roll out (doing back of the envelope math)
about 15K set tops -some of which are already deployed, but we're
talking second and third TVs as well. Once you start to take into
account bulk accounts like hospitals and hotels (one hotel in our
system has 2 TVs per room, and about 200 rooms), you can see a real
mess if you start taking out the analog feed too soon, or force
everyone to change out their box for something that can downconvert
easily. It will happen (most likely to be phased in during 2008), but
for now, unfortunately this is the only way to make sure everyone is
able to see. The real push for all digital service is bandwidth
reduction (and video over IP/Switched video), and cost savings on the
set tops. The cost savings is not huge, but enough to justify a short
term bandwidth crunch. Think like GM: If they save 12 cents per car,
and sell a million cars, that's $120,000 - which just paid that bean
counter's salary for the year.

Also, keep in mind that not all HD feeds are the same as the analog
feeds. KRMA-HD has different programming than KRMA analog, for example.