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Has there been any new news on HDTV in NZ?

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Anonymous
March 3, 2005 7:29:25 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Has there been any new news on HDTV in NZ?

As NZ's UHF band is allocated exactly like Australia's.

DVB-T test transmissions could theoretically be started in Auckland &
Wellington in 3 months using visiting DTV trained transmission tech people
from Australia.

A 5 kw DVB-T transmitter could easily cover the heavily populated parts of
Auckland with little difficulty.
Wellington's hills could prove to be a challenge, but the CBD coverage is
not a huge issue for the Wellington telecom tower.
Lessons leaned from Wellington could be easily re-applied in Chrischurch.

A practical HDTV test signal for TVNZ:

TV1
TV2
Maori TV (bandwidth limited during times when no programming is on)
RNZ Talk + Logo + upcoming programming ticker
RNZ Concert + Logo + upcoming programming ticker
Info (TV guide) channel

In full HD mode:
TV1
RNZ Talk + Logo
RNZ Concert + Logo
Info (TV guide) channel

More about : news hdtv

Anonymous
March 3, 2005 11:04:04 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On Thu, 3 Mar 2005 04:29:25 -0800, "Max Power"
<mikehack@u.washington.edu> wrote:

>Has there been any new news on HDTV in NZ?
>
>As NZ's UHF band is allocated exactly like Australia's.
>
>DVB-T test transmissions could theoretically be started in Auckland &
>Wellington in 3 months using visiting DTV trained transmission tech people
>from Australia.
>
>A 5 kw DVB-T transmitter could easily cover the heavily populated parts of
>Auckland with little difficulty.

A 5KW COFDM modulated signal might reach you.
But, you won' be able to reliably receive it.

Check out the DTV antenna install guidelines in the Australia..

http://www.dba.org.au/uploads/templates/files/DBA_Insta...

Notice, that they recommend the minimum signal Margin should be 9dB
and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)

Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
threshold where you can already receive and decode the DTV signal (17
to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
number to reduce COFDM's impulse noise issues.

--------


Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
TV signal at those levels. COFDM is an inferior digital broadcast
format and should not be confused with something practical.


B.T.W.. From by surfing of Australia's DTV forums.. All but one
network(Nine) has abandoned ALL HDTV programming. They sticking with
576p in order to gain a few more dB's of S/N ratio in an effort to
overcome COFDM's near fatal weakness.
Anonymous
March 3, 2005 12:20:11 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Tim Keating wrote:

> Check out the DTV antenna install guidelines in the Australia..
>
> http://www.dba.org.au/uploads/templates/files/DBA_Insta...
>
> Notice, that they recommend the minimum signal Margin should be 9dB
> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>
> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
> threshold where you can already receive and decode the DTV signal (17
> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
> number to reduce COFDM's impulse noise issues.
>
> --------
>
>
> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
> COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
> TV signal at those levels. COFDM is an inferior digital broadcast
> format and should not be confused with something practical.
>
>
> B.T.W.. From by surfing of Australia's DTV forums.. All but one
> network(Nine) has abandoned ALL HDTV programming. They sticking with
> 576p in order to gain a few more dB's of S/N ratio in an effort to
> overcome COFDM's near fatal weakness.


That's all very interesting. Where I live I am seeing that a minimum
margin of 1 to 2 dB is plenty acceptable! By this I do mean "minimum"
of course: several of our "local" stations are far (up to 25 miles)
beyond the horizon, and they fade in and out. If you set them up in the
spring or early summer, you are likely to need an 8 dB margin then to
get 2 dB come winter. If you set them up in the late summer or early
fall you might, if you are lucky or unlucky depending on how you count
it, need to get 25 dB margin to get 2 dB in the winter, such is the
nature of tropo propagation.


It's interesting that they have abandoned HDTV!

Doug McDonald
Related resources
March 3, 2005 2:29:22 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Max Power wrote:

<snipped>

Love your name, Mr. Power!
March 3, 2005 2:31:53 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Doug McDonald" <mcdonald@SnPoAM_scs.uiuc.edu> wrote in message
news:D 079vb$mta$1@news.ks.uiuc.edu...
> Tim Keating wrote:
>
>> Check out the DTV antenna install guidelines in the Australia..
>> http://www.dba.org.au/uploads/templates/files/DBA_Insta...
>>
>> Notice, that they recommend the minimum signal Margin should be 9dB
>> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>
>> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
>> threshold where you can already receive and decode the DTV signal (17
>> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
>> number to reduce COFDM's impulse noise issues. --------
>>
>>
>> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
>> COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>> TV signal at those levels. COFDM is an inferior digital broadcast
>> format and should not be confused with something practical. B.T.W.. From
>> by surfing of Australia's DTV forums.. All but one
>> network(Nine) has abandoned ALL HDTV programming. They sticking with
>> 576p in order to gain a few more dB's of S/N ratio in an effort to
>> overcome COFDM's near fatal weakness.
>
>
> That's all very interesting. Where I live I am seeing that a minimum
> margin of 1 to 2 dB is plenty acceptable! By this I do mean "minimum" of
> course: several of our "local" stations are far (up to 25 miles) beyond
> the horizon, and they fade in and out. If you set them up in the spring or
> early summer, you are likely to need an 8 dB margin then to get 2 dB come
> winter. If you set them up in the late summer or early fall you might, if
> you are lucky or unlucky depending on how you count it, need to get 25 dB
> margin to get 2 dB in the winter, such is the
> nature of tropo propagation.
>
>
> It's interesting that they have abandoned HDTV!
>
> Doug McDonald

Yes, it is interesting- but I guess where there are so many complaints about
switching a ~25 watt bulb in a partially enclosed metal enclosure (a
refrigerator) causing impulse noise and picture/sound loss, I'm not
surprised.

Standard digital [non-high definition] is just easier for everyone all
around. Broadcasters and customers.

They, and some others, do have a damned good system [if speeding around in
your car with live video playing is important to you].
Anonymous
March 3, 2005 4:54:02 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

Wasn't it Homer Simpson that had a "alter ego" Max Power name??

Sparky wrote:

> Max Power wrote:
>
> <snipped>
>
> Love your name, Mr. Power!


--
Ric Seyler
Anonymous
March 3, 2005 5:34:17 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Tim Keating wrote

> >A 5 kw DVB-T transmitter could easily cover the heavily populated parts of
> >Auckland with little difficulty.
>
> A 5KW COFDM modulated signal might reach you.
> But, you won't be able to reliably receive it.
>
What a load of rubbish!

The transmissions in Australian capital cities run 3.5Kw transmitter
power and cover the metropolitan areas with no trouble.
In most areas where analogue is unwatchable the digital signals are
perfect.
The stations have 5Kw transmitters but there is no need to run at
their
full power to give full coverage of their service areas.

>
> Notice, that they recommend the minimum signal Margin should be 9dB
> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>
> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
> threshold where you can already receive and decode the DTV signal (17
> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
> number to reduce COFDM's impulse noise issues.

The impulse noise issue is an issue in all systems, but is not a
problem with current COFDM boxes.

The obvious thing with margin is the more the better but it is
ridiculous to imply that one needs 20dB of margin for COFDM to work.
>
> --------
>
>
> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
> COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
> TV signal at those levels. COFDM is an inferior digital broadcast
> format and should not be confused with something practical.

What is practical? Surely you don't suggest that ATSC 8VSB is an
alternative
for anywhere?

It is possible to receive reliable signals in parts of the the Sydney
area on UHF from Wollongong and Newcastle transmissions on a simple
whip antenna (No outside antenna needed) of the 23Mb/s COFDM Muxs from
these adgacent service areas. Newcastle is about 100Km north and the
Wollongong
transmission site about 100Km south of Sydney.

I have a "Hi-Top" COFDM portable which is similar to the small DVD
players
with a fold-up 7 inch LCD screen and runs on a 12 volt battery.
I can use it virtually anywhere in Sydney and even in a moving vehicle
on its whip antenna.
>
> B.T.W.. From by surfing of Australia's DTV forums.. All but one
> network(Nine) has abandoned ALL HDTV programming. They sticking with
> 576p in order to gain a few more dB's of S/N ratio in an effort to
> overcome COFDM's near fatal weakness.

More rubbish!

ALL of the networks are transmitting full 19+ Mb/s or 23Mb/s datarates
on COFDM. Three of the networks run 23.052 Mb/s using 1080i HD and the
other
two run 19 Mbs using 576P HD. All are running multiple services
including
EPGs etc and it is leglislated that stations MUST run a concurrent SD
service
as well as the HD required service.
This means the datarates for the HD are round 14Mb/s typically and the
SD
about 5 Mb/s.

NO stations are running a simple SD low bitrate stream which would
need
lower C/N. All stations are running bitrates higher than that possible
with ATSC.

Far from giving up on HD the stations are in fact running much of
their
programming in HD. Most prime time shows are running in HD as well as
simultaneous SD.

As they are running so much HD programming they have stopped running
HD promo loops as they feel that there is no need to promote by loops
of "Pretty Pictures" any more. There are now so many viewers of HD
with
low cost (approx US$200) HD settop boxes now freely available that
they are no longer needed.
Anonymous
March 3, 2005 7:54:34 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Doug McDonald wrote:
> Tim Keating wrote:
>
>> Check out the DTV antenna install guidelines in the Australia..
>> http://www.dba.org.au/uploads/templates/files/DBA_Insta...
>>
>>
>> Notice, that they recommend the minimum signal Margin should be 9dB
>> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>
>> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
>> threshold where you can already receive and decode the DTV signal (17
>> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
>> number to reduce COFDM's impulse noise issues.
>> --------
>>
>>
>> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
>> COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>> TV signal at those levels. COFDM is an inferior digital broadcast
>> format and should not be confused with something practical.
>>
>> B.T.W.. From by surfing of Australia's DTV forums.. All but one
>> network(Nine) has abandoned ALL HDTV programming. They sticking with
>> 576p in order to gain a few more dB's of S/N ratio in an effort to
>> overcome COFDM's near fatal weakness.
>
>
>
> That's all very interesting. Where I live I am seeing that a minimum
> margin of 1 to 2 dB is plenty acceptable! By this I do mean "minimum"
> of course: several of our "local" stations are far (up to 25 miles)
> beyond the horizon, and they fade in and out. If you set them up in the
> spring or early summer, you are likely to need an 8 dB margin then to
> get 2 dB come winter. If you set them up in the late summer or early
> fall you might, if you are lucky or unlucky depending on how you count
> it, need to get 25 dB margin to get 2 dB in the winter, such is the
> nature of tropo propagation.
>
>
> It's interesting that they have abandoned HDTV!
>
> Doug McDonald

From what I read here they are not abandoning HD.

http://www.widescreentv.info/program.html

ABC, 10 and 9 are still at 1080i and meeting or exceeding the mandated
HD content required.

SBS and 7 are broadcasting using 576P which is somewhat better than
1080i though not considered HD in the US for some reason.

Nothing has changed from what they have been doing and I see nothing on
their forum's either.

As noted before 1080i can be received mobile with no problem even at 120
kmph, 25 miles from a station broadcasting at only a MEASLY 30 kW.

No impulse noise problems even in heavy traffic and while traveling
though the city.

http://www.dvb.org/documents/newsletters/DVB-SCENE-08.p... Page 13 for
story.

Bob Miller
Anonymous
March 3, 2005 7:54:35 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On Thu, 03 Mar 2005 16:54:34 GMT, Bob Miller <robmx@earthlink.net>
wrote:

>Doug McDonald wrote:
>> Tim Keating wrote:
>>
>>> Check out the DTV antenna install guidelines in the Australia..
>>> http://www.dba.org.au/uploads/templates/files/DBA_Insta...
>>>
>>>
>>> Notice, that they recommend the minimum signal Margin should be 9dB
>>> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>>
>>> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
>>> threshold where you can already receive and decode the DTV signal (17
>>> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
>>> number to reduce COFDM's impulse noise issues.
>>> --------
>>>
>>>
>>> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
>>> COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>>> TV signal at those levels. COFDM is an inferior digital broadcast
>>> format and should not be confused with something practical.
>>>
>>> B.T.W.. From by surfing of Australia's DTV forums.. All but one
>>> network(Nine) has abandoned ALL HDTV programming. They sticking with
>>> 576p in order to gain a few more dB's of S/N ratio in an effort to
>>> overcome COFDM's near fatal weakness.
>>
>>
>>
>> That's all very interesting. Where I live I am seeing that a minimum
>> margin of 1 to 2 dB is plenty acceptable! By this I do mean "minimum"
>> of course: several of our "local" stations are far (up to 25 miles)
>> beyond the horizon, and they fade in and out. If you set them up in the
>> spring or early summer, you are likely to need an 8 dB margin then to
>> get 2 dB come winter. If you set them up in the late summer or early
>> fall you might, if you are lucky or unlucky depending on how you count
>> it, need to get 25 dB margin to get 2 dB in the winter, such is the
>> nature of tropo propagation.
>>
>>
>> It's interesting that they have abandoned HDTV!
>>
>> Doug McDonald
>
> From what I read here they are not abandoning HD.
>
>http://www.widescreentv.info/program.html
>
>ABC, 10 and 9 are still at 1080i and meeting or exceeding the mandated
>HD content required.


http://www.dtvforum.info/lofiversion/index.php/t15077.h...


ABC.. TEN... HDTV... RIP..
March 3, 2005 8:24:03 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Max Power" <mikehack@u.washington.edu> wrote in message
news:D 06vvf$h40$1@gnus01.u.washington.edu...
> Has there been any new news on HDTV in NZ?
> As NZ's UHF band is allocated exactly like Australia's.
> DVB-T test transmissions could theoretically be started in Auckland &
> Wellington in 3 months using visiting DTV trained transmission tech people
> from Australia.
> A 5 kw DVB-T transmitter could easily cover the heavily populated parts of
> Auckland with little difficulty.
> Wellington's hills could prove to be a challenge, but the CBD coverage is
> not a huge issue for the Wellington telecom tower.
> Lessons leaned from Wellington could be easily re-applied in Chrischurch.
> A practical HDTV test signal for TVNZ:
> TV1
> TV2
> Maori TV (bandwidth limited during times when no programming is on)
> RNZ Talk + Logo + upcoming programming ticker
> RNZ Concert + Logo + upcoming programming ticker
> Info (TV guide) channel
> In full HD mode:
> TV1
> RNZ Talk + Logo
> RNZ Concert + Logo
> Info (TV guide) channel

I posted this here about a year ago, FWIW:

http://makeashorterlink.com/?L13A2199A

Containing this link:
http://www.executive.govt.nz/minister/hobbs/digital/iss...
Anonymous
March 3, 2005 10:26:22 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On 3 Mar 2005 14:34:17 -0800, 100246.2055@compuserve.com (Ian
Mackenzie) wrote:

>Tim Keating wrote
>
>> >A 5 kw DVB-T transmitter could easily cover the heavily populated parts of
>> >Auckland with little difficulty.
>>
>> A 5KW COFDM modulated signal might reach you.
>> But, you won't be able to reliably receive it.
>>
>What a load of rubbish!
>
>The transmissions in Australian capital cities run 3.5Kw transmitter
>power and cover the metropolitan areas with no trouble.
>In most areas where analogue is unwatchable the digital signals are
>perfect.
>The stations have 5Kw transmitters but there is no need to run at
>their
>full power to give full coverage of their service areas.
>

Hmmm.. something missing from this quote.. ... Oh yeah.. the link to
DTV antenna install guidelines provided by the Digital Broadcasting
Australia (association)..


Here is a list of their members..
http://www.dba.org.au/index.asp?sectionID=30

Hmmm... looks like all Aussie TV networks are members..


>>
>> Notice, that they recommend the minimum signal Margin should be 9dB
>> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>
>> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
>> threshold where you can already receive and decode the DTV signal (17
>> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
>> number to reduce COFDM's impulse noise issues.
>
>The impulse noise issue is an issue in all systems, but is not a
>problem with current COFDM boxes.

Not really.. Impulse noise doesn't bother 8VSB nearly as much.
( You loose a few packets.. maybe.. one would have a hard time
finding the display anomalies. )

>
>The obvious thing with margin is the more the better but it is
>ridiculous to imply that one needs 20dB of margin for COFDM to work.

So that it will work reliably in a typical Aussie residential
installation. It's their recommendation, (for obvious reasons).

P.S Why did you forget to quote the link?? Embarrassed??

It's the recommendations by your own Digital Broadcasting Australia
organization. Here is another copy of the link so you can read it
this time around.

Check out the DTV antenna install guidelines in the Australia..
http://www.dba.org.au/uploads/templates/files/DBA_Insta...


>>
>> --------
>>
>>
>> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
>> COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>> TV signal at those levels. COFDM is an inferior digital broadcast
>> format and should not be confused with something practical.
>
>What is practical? Surely you don't suggest that ATSC 8VSB is an
>alternative for anywhere?

It works a whole lot better than the alternatives.

Europe and Australia would be better off dumping COFDM and
switching to 8VSB. Instead you'll probably be sentenced to low def
programming for a couple more decades.. Ouch...

>
>It is possible to receive reliable signals in parts of the the Sydney
>area on UHF from Wollongong and Newcastle transmissions on a simple
>whip antenna (No outside antenna needed) of the 23Mb/s COFDM Muxs from
>these adgacent service areas. Newcastle is about 100Km north and the
>Wollongong
>transmission site about 100Km south of Sydney.
>
>I have a "Hi-Top" COFDM portable which is similar to the small DVD
>players
>with a fold-up 7 inch LCD screen and runs on a 12 volt battery.
>I can use it virtually anywhere in Sydney and even in a moving vehicle
>on its whip antenna.
>>
>> B.T.W.. From by surfing of Australia's DTV forums.. All but one
>> network(Nine) has abandoned ALL HDTV programming. They sticking with
>> 576p in order to gain a few more dB's of S/N ratio in an effort to
>> overcome COFDM's near fatal weakness.
>
>More rubbish!

I've posted the link on other posts..

http://www.dtvforum.info/lofiversion/index.php/t15077.h...

ABC TEN.. HDTV, R.I.P... was 1080i50(x1920) is now 576p(x720)..

That leaves only "NINE" still broadcasting 1080i50..

>ALL of the networks are transmitting full 19+ Mb/s or 23Mb/s datarates
>on COFDM. Three of the networks run 23.052 Mb/s using 1080i HD and the
>other
>two run 19 Mbs using 576P HD. All are running multiple services
>including

From what I've read it's closer to 21.3Mb/sec..

>EPGs etc and it is leglislated that stations MUST run a concurrent SD
>service
>as well as the HD required service.
>This means the datarates for the HD are round 14Mb/s typically and the
>SD
>about 5 Mb/s.

From what I hear SD is consuming 6Mb/s .. which is somewhat high..
Especially since the frame SD refresh rate is somewhat lower than
ours .. 50 Hz(v 60Hz). Sounds like they're upping the FEC in an
effort compensate for the modulation scheme.

B.T.W. My local PBS(H)DTB station has no problem running a
High def 1080i60 channel along with two low def's 480i all at the same
time.

>
>NO stations are running a simple SD low bitrate stream which would
>need lower C/N. All stations are running bitrates higher than that possible
>with ATSC.

Doesn't sound like it.. TEN is now broadcasting 576p at a 8.5Mb/s
data rate. (Their new HD standard)..

>Far from giving up on HD the stations are in fact running much of
>their
>programming in HD. Most prime time shows are running in HD as well as
>simultaneous SD.

Now that a minister has redefined EDTV 576p25(x720) to be HD. I'm
not surprised by your statements. see
http://www.dba.org.au/index.asp?sectionID=15


In the US, anything less than 720p(x1280) is not considered to be
hi-def..
http://support.gateway.com/s/CsmrEltrncs/DigitalTV/Shar...

>
>As they are running so much HD programming they have stopped running
>HD promo loops as they feel that there is no need to promote by loops
>of "Pretty Pictures" any more. There are now so many viewers of HD

http://www.dba.org.au/newsletter/IB-FebMar05-full.asp#P...

"By end of 2004 the estimated number of digital television set top
box receivers and integrated digital tv sets in Australian homes was
658,000, with more than 400,000 units sold in the 12 months to
December 2004"

Only 650K.. tsk..tsk.. another whopper of a lie..
(A vast majority of them can't decode anything over 576p).


>with
>low cost (approx US$200) HD settop boxes now freely available that
>they are no longer needed.

Sound's like this is another BM clone..
Declare red(ED) is green(HD) and then claim how all the green(HD) +
red(ED) prices have dropped.


None the less.. we in the US consider anything less than 720p(x1280)
to be less than high def.. Last time I checked, Australian
720p/1080i receivers still run in the 500$ range..
Anonymous
March 3, 2005 10:42:35 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On 3 Mar 2005 14:34:17 -0800, 100246.2055@compuserve.com (Ian
Mackenzie) wrote:

>Tim Keating wrote
>
>> >A 5 kw DVB-T transmitter could easily cover the heavily populated parts of
>> >Auckland with little difficulty.
>>
>> A 5KW COFDM modulated signal might reach you.
>> But, you won't be able to reliably receive it.
>>
>What a load of rubbish!
>
>The transmissions in Australian capital cities run 3.5Kw transmitter
>power and cover the metropolitan areas with no trouble.
>In most areas where analogue is unwatchable the digital signals are
>perfect.
>The stations have 5Kw transmitters but there is no need to run at
>their
>full power to give full coverage of their service areas.
>

Hmmm.. something missing from this quote.. ... Oh yeah.. the link to
DTV antenna install guidelines provided by the Digital Broadcasting
Australia (association)..


Here is a list of their members..
http://www.dba.org.au/index.asp?sectionID=30

Hmmm... looks like all Aussie TV networks are members..


>>
>> Notice, that they recommend the minimum signal Margin should be 9dB
>> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>
>> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
>> threshold where you can already receive and decode the DTV signal (17
>> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
>> number to reduce COFDM's impulse noise issues.
>
>The impulse noise issue is an issue in all systems, but is not a
>problem with current COFDM boxes.

Not really.. Impulse noise doesn't bother 8VSB nearly as much.
( You loose a few packets.. maybe.. one would have a hard time
finding the display anomalies. )

>
>The obvious thing with margin is the more the better but it is
>ridiculous to imply that one needs 20dB of margin for COFDM to work.

So that it will work reliably in a typical Aussie residential
installation. It's their recommendation, (for obvious reasons).

P.S Why did you forget to quote the link?? Embarrassed??

It's the recommendations by your own Digital Broadcasting Australia
organization. Here is another copy of the link so you can read it
this time around.

Check out the DTV antenna install guidelines in the Australia..
http://www.dba.org.au/uploads/templates/files/DBA_Insta...


>>
>> --------
>>
>>
>> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
>> COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>> TV signal at those levels. COFDM is an inferior digital broadcast
>> format and should not be confused with something practical.
>
>What is practical? Surely you don't suggest that ATSC 8VSB is an
>alternative for anywhere?

It works a whole lot better than the alternatives.

Europe and Australia would be better off dumping COFDM and
switching to 8VSB. Instead you'll probably be sentenced to low def
programming for a couple more decades.. Ouch...

>
>It is possible to receive reliable signals in parts of the the Sydney
>area on UHF from Wollongong and Newcastle transmissions on a simple
>whip antenna (No outside antenna needed) of the 23Mb/s COFDM Muxs from
>these adgacent service areas. Newcastle is about 100Km north and the
>Wollongong
>transmission site about 100Km south of Sydney.
>
>I have a "Hi-Top" COFDM portable which is similar to the small DVD
>players
>with a fold-up 7 inch LCD screen and runs on a 12 volt battery.
>I can use it virtually anywhere in Sydney and even in a moving vehicle
>on its whip antenna.
>>
>> B.T.W.. From by surfing of Australia's DTV forums.. All but one
>> network(Nine) has abandoned ALL HDTV programming. They sticking with
>> 576p in order to gain a few more dB's of S/N ratio in an effort to
>> overcome COFDM's near fatal weakness.
>
>More rubbish!

I've posted the link on other posts..

http://www.dtvforum.info/lofiversion/index.php/t15077.h...

ABC . HDTV, R.I.P... was 1080i50(x1920) is now 576p(x720)..

>ALL of the networks are transmitting full 19+ Mb/s or 23Mb/s datarates
>on COFDM. Three of the networks run 23.052 Mb/s using 1080i HD and the
>other
>two run 19 Mbs using 576P HD. All are running multiple services
>including

From what I've read it's closer to 21.3Mb/sec..

>EPGs etc and it is leglislated that stations MUST run a concurrent SD
>service
>as well as the HD required service.
>This means the datarates for the HD are round 14Mb/s typically and the
>SD
>about 5 Mb/s.

From what I hear SD is consuming 6Mb/s .. which is somewhat high..
Especially since the frame SD refresh rate is somewhat lower than
ours .. 50 Hz(v 60Hz). Sounds like they're upping the FEC in an
effort compensate for the modulation scheme.

B.T.W. My local PBS(H)DTB station has no problem running a
High def 1080i60 channel along with two low def's 480i all at the same
time.

>
>NO stations are running a simple SD low bitrate stream which would
>need lower C/N. All stations are running bitrates higher than that possible
>with ATSC.

Doesn't sound like it.. TEN is now broadcasting 576p at a 8.5Mb/s
data rate. (Their new HD standard)..

>Far from giving up on HD the stations are in fact running much of
>their
>programming in HD. Most prime time shows are running in HD as well as
>simultaneous SD.

Now that a minister has redefined EDTV 576p25(x720) to be HD. I'm
not surprised by your statements. see
http://www.dba.org.au/index.asp?sectionID=15


In the US, anything less than 720p(x1280) is not considered to be
hi-def..
http://support.gateway.com/s/CsmrEltrncs/DigitalTV/Shar...

>
>As they are running so much HD programming they have stopped running
>HD promo loops as they feel that there is no need to promote by loops
>of "Pretty Pictures" any more. There are now so many viewers of HD

http://www.dba.org.au/newsletter/IB-FebMar05-full.asp#P...

"By end of 2004 the estimated number of digital television set top
box receivers and integrated digital tv sets in Australian homes was
658,000, with more than 400,000 units sold in the 12 months to
December 2004"

Only 650K.. tsk..tsk.. another whopper of a lie..
(A vast majority of them can't decode anything over 576p).


>with
>low cost (approx US$200) HD settop boxes now freely available that
>they are no longer needed.

Sound's like this is another BM clone..
Declare red(ED) is green(HD) and then claim how all the green(HD) +
red(ED) prices have dropped.


None the less.. we in the US consider anything less than 720p(x1280)
to be less than high def.. Last time I checked, Australian
720p/1080i receivers still run in the 500$ range..
Anonymous
March 4, 2005 1:05:48 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Tim Keating wrote:
> On Thu, 03 Mar 2005 16:54:34 GMT, Bob Miller <robmx@earthlink.net>
> wrote:
>
>
>>Doug McDonald wrote:
>>
>>>Tim Keating wrote:
>>>
>>>
>>>>Check out the DTV antenna install guidelines in the Australia..
>>>>http://www.dba.org.au/uploads/templates/files/DBA_Insta...
>>>>
>>>>
>>>> Notice, that they recommend the minimum signal Margin should be 9dB
>>>>and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>>>
>>>>Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
>>>>threshold where you can already receive and decode the DTV signal (17
>>>>to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
>>>>number to reduce COFDM's impulse noise issues.
>>>>--------
>>>>
>>>>
>>>>Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
>>>>COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>>>>TV signal at those levels. COFDM is an inferior digital broadcast
>>>>format and should not be confused with something practical.
>>>>
>>>>B.T.W.. From by surfing of Australia's DTV forums.. All but one
>>>>network(Nine) has abandoned ALL HDTV programming. They sticking with
>>>>576p in order to gain a few more dB's of S/N ratio in an effort to
>>>>overcome COFDM's near fatal weakness.
>>>
>>>
>>>
>>>That's all very interesting. Where I live I am seeing that a minimum
>>>margin of 1 to 2 dB is plenty acceptable! By this I do mean "minimum"
>>>of course: several of our "local" stations are far (up to 25 miles)
>>>beyond the horizon, and they fade in and out. If you set them up in the
>>>spring or early summer, you are likely to need an 8 dB margin then to
>>>get 2 dB come winter. If you set them up in the late summer or early
>>>fall you might, if you are lucky or unlucky depending on how you count
>>>it, need to get 25 dB margin to get 2 dB in the winter, such is the
>>>nature of tropo propagation.
>>>
>>>
>>>It's interesting that they have abandoned HDTV!
>>>
>>>Doug McDonald
>>
>>From what I read here they are not abandoning HD.
>>
>>http://www.widescreentv.info/program.html
>>
>>ABC, 10 and 9 are still at 1080i and meeting or exceeding the mandated
>>HD content required.
>
>
>
> http://www.dtvforum.info/lofiversion/index.php/t15077.h...
>
>
> ABC.. TEN... HDTV... RIP..

Looks like you are right. Multicasting wins out again.

I see ABC going to 576P but I see nothing about TEN doing this.

Bob Miller
Anonymous
March 4, 2005 2:35:56 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Ian Mackenzie wrote:
> Tim Keating wrote
>
>
>>>A 5 kw DVB-T transmitter could easily cover the heavily populated parts of Auckland with little difficulty.
>>
>> A 5KW COFDM modulated signal might reach you. But, you won't be able to reliably receive it.
>>
>
> What a load of rubbish!
>
> The transmissions in Australian capital cities run 3.5Kw transmitter power and cover the metropolitan areas with no trouble.
> In most areas where analogue is unwatchable the digital signals are perfect.
> The stations have 5Kw transmitters but there is no need to run at their full power to give full coverage of their service areas.
>
>
>> Notice, that they recommend the minimum signal Margin should be 9dB and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>
>>Note: That's MARGIN !!! not overall S/N.. Margin starts out at a threshold where you can already receive and decode the DTV signal (17
>>to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that number to reduce COFDM's impulse noise issues.
>
>
> The impulse noise issue is an issue in all systems, but is not a problem with current COFDM boxes.
>
> The obvious thing with margin is the more the better but it is ridiculous to imply that one needs 20dB of margin for COFDM to work.
>
>>--------
>>
>>
>>Net result COFDM Needs 25 to 40dB of S/N to receive a reliable COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>>TV signal at those levels. COFDM is an inferior digital broadcast format and should not be confused with something practical.
>
>
> What is practical? Surely you don't suggest that ATSC 8VSB is an alternative for anywhere?

I think he just might. Some are insanely parochial here. Don't get out much.
>
> It is possible to receive reliable signals in parts of the the Sydney area on UHF from Wollongong and Newcastle transmissions on a simple
> whip antenna (No outside antenna needed) of the 23Mb/s COFDM Muxs from these adgacent service areas. Newcastle is about 100Km north and the
> Wollongong transmission site about 100Km south of Sydney.
>
> I have a "Hi-Top" COFDM portable which is similar to the small DVD players with a fold-up 7 inch LCD screen and runs on a 12 volt battery.
> I can use it virtually anywhere in Sydney and even in a moving vehicle on its whip antenna.

In the video of mobile reception of DTV in Manhattan (below) the unit
that looks like a weird laptop (not the laptop of which there is one
also) is a Hi-Top receiver. The neat thing about the Hi-Top is that it
is a regular STB with its one LCD screen so you can unhook it and take
it with you anywhere. Plugs into the cigarette lighter in your car also.

Hi Top
http://www.hitopcomm.com/products/products.html#

Video
www.viacel.com/bob.wmv

This video was shot using a SINGLE 100 Watt transmitter, we had no
repeaters or SFN, and it was in a much more challenging environment than
any in OZ so when they talk of multiple transmitters and 5 kW in OZ
cities, that is amazingly more powerful than what this video represents.

The HD Mobile video story was from a Sydney station at 30 kW however.
>
>>B.T.W.. From by surfing of Australia's DTV forums.. All but one network(Nine) has abandoned ALL HDTV programming. They sticking with
>>576p in order to gain a few more dB's of S/N ratio in an effort to overcome COFDM's near fatal weakness.
>
>
> More rubbish!
>
> ALL of the networks are transmitting full 19+ Mb/s or 23Mb/s datarates on COFDM. Three of the networks run 23.052 Mb/s using 1080i HD and the
> other two run 19 Mbs using 576P HD. All are running multiple services including EPGs etc and it is leglislated that stations MUST run a concurrent SD
> service as well as the HD required service. This means the datarates for the HD are round 14Mb/s typically and the SD about 5 Mb/s.

It may be that ABC has gone 576P according to what I have read. I think
that this qualifies as HD personally since most people have displays
that are 42" or less anyway. 576P, 720P and 1080P are real HD. 1080i is
holdover c**p from analog days. Most displays are progressive when you
get to the larger size screens.
>
> NO stations are running a simple SD low bitrate stream which would need lower C/N. All stations are running bitrates higher than that possible
> with ATSC.
>
> Far from giving up on HD the stations are in fact running much of their programming in HD. Most prime time shows are running in HD as well as
> simultaneous SD.
>
> As they are running so much HD programming they have stopped running HD promo loops as they feel that there is no need to promote by loops
> of "Pretty Pictures" any more. There are now so many viewers of HD with low cost (approx US$200) HD settop boxes now freely available that
> they are no longer needed.
Anonymous
March 4, 2005 2:51:11 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Ian Mackenzie" <100246.2055@compuserve.com> wrote:

> The impulse noise issue is an issue in all systems, but is not a
> problem with current COFDM boxes.

Impulse noise was more of an issue with COFDM, because DVB-T elected not
to do inner interleaving (it was an option). But somehow that problem
was patched in the newer receivers.

Similarly, in 8-VSB, multipath distortion was problem, particularly with
pre-echo. But that too *seems* to have been successfully overcome with
the most recent receiver designs. Too bad it took so *&% long.

>> B.T.W.. From by surfing of Australia's DTV forums.. All but one
>> network(Nine) has abandoned ALL HDTV programming. They sticking
>> with
>> 576p in order to gain a few more dB's of S/N ratio in an effort to
>> overcome COFDM's near fatal weakness.
>
> More rubbish!
>
> ALL of the networks are transmitting full 19+ Mb/s or 23Mb/s datarates
> on COFDM. Three of the networks run 23.052 Mb/s using 1080i HD and the
> other
> two run 19 Mbs using 576P HD. All are running multiple services
> including
> EPGs etc and it is leglislated that stations MUST run a concurrent SD
> service
> as well as the HD required service.

Yes, that comment didn't make sense to me either. SD is no easier to
receive than HD *unless* the COFDM constellation is reduced for the
channel when it carries SD streams. But I had not seen where they did
any such thing in Aussie COFDM. In fact, as far as I know, they still
use 64-QAM vs backing off to 16-QAM as the Euro DTT systems did. And
Ian's numbers seem to support this.

> Far from giving up on HD the stations are in fact running much of
> their
> programming in HD. Most prime time shows are running in HD as well as
> simultaneous SD.

Too bad all STBs were not capable of at least receiving HD, so they
could have avoided the wasteful simulcasts. I think that was a good
decision the ATSC made at the very start. Make everyone compatible with
the HD broadcasts, whether or not they actually display HD quality.
Avoids simulcasting entirely.

Bert
Anonymous
March 4, 2005 2:56:56 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Bob Miller wrote:
> Ian Mackenzie wrote:
>
>> Tim Keating wrote

>>
>> I have a "Hi-Top" COFDM portable which is similar to the small DVD players with a fold-up 7 inch LCD screen and runs on a 12 volt battery.
>> I can use it virtually anywhere in Sydney and even in a moving vehicle on its whip antenna.
>
>
> In the video of mobile reception of DTV in Manhattan (below) the unit that looks like a weird laptop (not the laptop of which there is one
> also) is a Hi-Top receiver. The neat thing about the Hi-Top is that it is a regular STB with its one LCD screen so you can unhook it and take
> it with you anywhere. Plugs into the cigarette lighter in your car also.
>
> Hi Top
> http://www.hitopcomm.com/products/products.html#
>
I should have also mentioned. At this site click on "Ti-dTV" and
"Digital TV Antenna" to see the unit Ian is using and the overpriced
antenna he may be using. The one on the right is the best and cheapest
AFAIK.

That is all you would need in your home or car with COFDM in most
coverage areas well designed. Obvioulsy the car is the more challenging
environment and this antenna works there. The best antenna I ever used
was similar in size to the one on the left but a simple whip.

Bob Miller
Anonymous
March 4, 2005 3:25:27 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

I agree with the analysis of your posted links.
However, without actually starting transmissions in AUK, WEL and CHCH the
ball will never get rolling.

I don't see a speedy HDTV transition in towns that are less than 30,000
people.
However, due to NZ hilly terrain it is easy for one local commercial TV
station to switch to HD -- like TV4.
The local TV4 HD repeater could then carry TV1 + (TV2/TV3) in its bundle.

In the case of TV4, its disappearance from local broadcast would not be
heavily missed.
Also, SKY TV's transmitter network could be refitted for HD broadcast and
used during the transition.

There are several ways the transition could be made to HD that are
economically viable, it just takes some work and experimentation. Certainly
a nation that beat the US to powered flight can figure out HDTV!

>> A 5 kw DVB-T transmitter could easily cover the heavily populated parts
>> of Auckland with little difficulty.
>> Wellington's hills could prove to be a challenge, but the CBD coverage is
>> not a huge issue for the Wellington telecom tower.
>> Lessons leaned from Wellington could be easily re-applied in Chrischurch.
>> A practical HDTV test signal for TVNZ:
> > TV1
>> TV2
>> Maori TV (bandwidth limited during times when no programming is on)
>> RNZ Talk + Logo + upcoming programming ticker
>> RNZ Concert + Logo + upcoming programming ticker
>> Info (TV guide) channel
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
I posted this here about a year ago, FWIW:
>
> http://makeashorterlink.com/?L13A2199A
>
> Containing this link:
> http://www.executive.govt.nz/minister/hobbs/digital/iss...
Anonymous
March 4, 2005 3:57:07 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

In my message I was implying the densely populated parts of Auckland...
[And maybe that ghastly Huntley, where the power station is...]

However, I always got the impression that HD in Australia works so well
becuase you have dry earth and flat land.
Essentally, the transmission conditions are not that different from Mars!

NZ is wetter and has more hills.
Dry earth? Wots that?
Flat land? Well maybe around Chch.

DVB-T transmission margins would have to be 2db higher (C/N or S/N?) than
what is working acceptably well in Australia.
I would expect that in a place like Germany, there would be a 2.5 db to 3 db
margin difference from what is working in Australia, mainly due to higher
urban RF (RFI) noise in the frequency range 100 khz ... 3 mhz.

Australia has very low urban RFI, save Melbourne and its trams.
Perth's electric trains don't spark too much...


>>>A 5 kw DVB-T transmitter could easily cover the heavily populated parts
>>>of
>>>Auckland with little difficulty.
>>
>> A 5KW COFDM modulated signal might reach you.
>> But, you won't be able to reliably receive it.
>>
> What a load of rubbish!
>
> The transmissions in Australian capital cities run 3.5Kw transmitter
> power and cover the metropolitan areas with no trouble.
> In most areas where analogue is unwatchable the digital signals are
> perfect.
> The stations have 5Kw transmitters but there is no need to run at
> their full power to give full coverage of their service areas.
Anonymous
March 4, 2005 6:18:55 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Tim Keating wrote:
> On 3 Mar 2005 14:34:17 -0800, 100246.2055@compuserve.com (Ian
> Mackenzie) wrote:
>
>
>>Tim Keating wrote
>>
>>
>>>>A 5 kw DVB-T transmitter could easily cover the heavily populated parts of Auckland with little difficulty.
>>>
>>> A 5KW COFDM modulated signal might reach you. But, you won't be able to reliably receive it.
>>>
>>
>>What a load of rubbish!
>>
>>The transmissions in Australian capital cities run 3.5Kw transmitter power and cover the metropolitan areas with no trouble.
>>In most areas where analogue is unwatchable the digital signals are perfect.
>>The stations have 5Kw transmitters but there is no need to run at their full power to give full coverage of their service areas.
>>
>
>
> Hmmm.. something missing from this quote.. ... Oh yeah.. the link to DTV antenna install guidelines provided by the Digital Broadcasting
> Australia (association)..
>
>
> Here is a list of their members..
> http://www.dba.org.au/index.asp?sectionID=30
>
> Hmmm... looks like all Aussie TV networks are members..
>
>
>
>>> Notice, that they recommend the minimum signal Margin should be 9dB and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
>>>
>>>Note: That's MARGIN !!! not overall S/N.. Margin starts out at a threshold where you can already receive and decode the DTV signal (17
>>>to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that number to reduce COFDM's impulse noise issues.
>>
>>The impulse noise issue is an issue in all systems, but is not a problem with current COFDM boxes.
>
>
> Not really.. Impulse noise doesn't bother 8VSB nearly as much. ( You loose a few packets.. maybe.. one would have a hard time
> finding the display anomalies. )
>
>
>>The obvious thing with margin is the more the better but it is ridiculous to imply that one needs 20dB of margin for COFDM to work.
>
>
> So that it will work reliably in a typical Aussie residential installation. It's their recommendation, (for obvious reasons).
>
> P.S Why did you forget to quote the link?? Embarrassed??
>
> It's the recommendations by your own Digital Broadcasting Australia organization. Here is another copy of the link so you can read it
> this time around.
>
> Check out the DTV antenna install guidelines in the Australia..
> http://www.dba.org.au/uploads/templates/files/DBA_Insta...
>
>
>>>
>>>Net result COFDM Needs 25 to 40dB of S/N to receive a reliable COFDM signal. I.E. Most people can pickup a perfect (old style) PAL
>>>TV signal at those levels. COFDM is an inferior digital broadcast format and should not be confused with something practical.
>>
>>What is practical? Surely you don't suggest that ATSC 8VSB is an alternative for anywhere?
>
>
> It works a whole lot better than the alternatives.
>
> Europe and Australia would be better off dumping COFDM and switching to 8VSB. Instead you'll probably be sentenced to low def
> programming for a couple more decades.. Ouch...
>
>
>>It is possible to receive reliable signals in parts of the the Sydney area on UHF from Wollongong and Newcastle transmissions on a simple
>>whip antenna (No outside antenna needed) of the 23Mb/s COFDM Muxs from these adgacent service areas. Newcastle is about 100Km north and the
>>Wollongong transmission site about 100Km south of Sydney.
>>
>>I have a "Hi-Top" COFDM portable which is similar to the small DVD players with a fold-up 7 inch LCD screen and runs on a 12 volt battery.
>>I can use it virtually anywhere in Sydney and even in a moving vehicle on its whip antenna.
>>
>>>B.T.W.. From by surfing of Australia's DTV forums.. All but one network(Nine) has abandoned ALL HDTV programming. They sticking with
>>>576p in order to gain a few more dB's of S/N ratio in an effort to overcome COFDM's near fatal weakness.
>>
>>More rubbish!
>
>
> I've posted the link on other posts..
>
> http://www.dtvforum.info/lofiversion/index.php/t15077.h...
>
> ABC TEN.. HDTV, R.I.P... was 1080i50(x1920) is now 576p(x720)..

Again this site says nothing about 10 going to 576P only ABC.

I find it amusing that Tim is all excited about a channel in OZ deciding
to downgrade/upgrade from 1080i to 576P. In OZ they have to do HDTV and
they have decided that 576P is HD. The fact is that in any given frame
576 is more than 540 which is what 1080i is. If nothing else the two are
not that far apart. The purist in me wants to see 1080i removed from the
HD digital list since it is really a legacy from analog.

But here is a country, OZ, that MANDATES HD while here in the US
broadcasters can do all the 480i they want and to see the effort they
have put into trying (still trying after all these years and even after
last weeks FCC turndown vote) multicast must carry they plan on doing a
lot of 480i. I predicted back in 1999 that chose COFDM or 8-VSB,
broadcasters would do lots of multicasting. At that time COFDM was
supposed to facilitate multicasting. I argued then and I do now that the
only way to limit multicasting is to MANDATE HDTV. Didn't do it and OTA
is going to be mostly SD/ED and pretend HD in the US.

Now we have a channel in OZ that goes to 576P, more than enough to
saturate 97% of all digital HD displays sold in the US so far and Tim
would have us believe that OZ has dropped the HD ball. Hardly, but it
must be tempting in OZ since the reality is that given the choice most
people in OZ are choosing Wide Screen 576i digital.

In the US people are just ignoring the whole thing, buying real HDTV
sets to watch 480i DVDs. Weirdly ignorant but understandable in a
country with such a bad modulation as 8-VSB.


>
> That leaves only "NINE" still broadcasting 1080i50..
>
>
>>ALL of the networks are transmitting full 19+ Mb/s or 23Mb/s datarates on COFDM. Three of the networks run 23.052 Mb/s using 1080i HD and the
>>other two run 19 Mbs using 576P HD. All are running multiple services including
>
>
> From what I've read it's closer to 21.3Mb/sec..
>
>
>>EPGs etc and it is leglislated that stations MUST run a concurrent SD service as well as the HD required service.
>>This means the datarates for the HD are round 14Mb/s typically and the SD about 5 Mb/s.
>
>
> From what I hear SD is consuming 6Mb/s .. which is somewhat high..
> Especially since the frame SD refresh rate is somewhat lower than ours .. 50 Hz(v 60Hz). Sounds like they're upping the FEC in an
> effort compensate for the modulation scheme.
>
> B.T.W. My local PBS(H)DTB station has no problem running a High def 1080i60 channel along with two low def's 480i all at the same time.
>
>
>>NO stations are running a simple SD low bitrate stream which would need lower C/N. All stations are running bitrates higher than that possible with ATSC.
>
>
> Doesn't sound like it.. TEN is now broadcasting 576p at a 8.5Mb/s data rate. (Their new HD standard)..

Can find no evidence of this.
>
>
>>Far from giving up on HD the stations are in fact running much of their programming in HD. Most prime time shows are running in HD as well as simultaneous SD.
>
>
> Now that a minister has redefined EDTV 576p25(x720) to be HD. I'm not surprised by your statements. see http://www.dba.org.au/index.asp?sectionID=15
>
>
> In the US, anything less than 720p(x1280) is not considered to be hi-def..


http://support.gateway.com/s/CsmrEltrncs/DigitalTV/Shar...
>
>
>>As they are running so much HD programming they have stopped running HD promo loops as they feel that there is no need to promote by loops
>>of "Pretty Pictures" any more. There are now so many viewers of HD
>
>
> http://www.dba.org.au/newsletter/IB-FebMar05-full.asp#P...
>
> "By end of 2004 the estimated number of digital television set top box receivers and integrated digital tv sets in Australian homes was
> 658,000, with more than 400,000 units sold in the 12 months to December 2004"
>
> Only 650K.. tsk..tsk.. another whopper of a lie..
> (A vast majority of them can't decode anything over 576p).

No lie that I can see. They say they have sold 685,000 SD, HD and
integrated DTV receivers and they have period. They do not say that they
have sold 685,000 receivers that are HD by America's definition of HD.
In Australia they have a choice, called freedom to chose, and the
customer is choosing not to buy HD OTA receivers in most cases. Do you
think it is or would be any different in the US? The only difference
here is that the receivers for sale don't work so well and no low costs
SD or ED versions are available. The lowest price SD receiver in OZ is
now $99 OZ or $77 US. Pretty good for such a small market.

>
>>with low cost (approx US$200) HD settop boxes now freely available that they are no longer needed.
>
>
> Sound's like this is another BM clone..
> Declare red(ED) is green(HD) and then claim how all the green(HD) + red(ED) prices have dropped.
>
>
> None the less.. we in the US consider anything less than 720p(x1280) to be less than high def.. Last time I checked, Australian
> 720p/1080i receivers still run in the 500$ range..

OZ is a 4 million household market with an unusual 7 MHz channel size.
Most critics of their DTV transition thought that NO manufacturer would
build ANY receiver for OZ. OZ now has twice as many models of receiver
that the US has. In the US it is debatable whether we have reached ONE%
of homes with DTV OTA receivers while in OZ they are at 17.1%. I think
the latest STB sales figures from the FCC suggest 187,000 OTA receivers
sold in the US over the last almost EIGHT years.

And in the US the ONE manufacturer that can build a decent 5th gen
receiver has decided not to.

Bob Miller
Anonymous
March 4, 2005 8:27:37 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Tim Keating wrote more rubbish.....getting further off track.

I said:
> >The transmissions in Australian capital cities run 3.5Kw transmitter
> >power and cover the metropolitan areas with no trouble.
> >In most areas where analogue is unwatchable the digital signals are
> >perfect.
> >The stations have 5Kw transmitters but there is no need to run at
> >their full power to give full coverage of their service areas.

I stand by those statements.
> >
>
> Hmmm.. something missing from this quote.. ... Oh yeah.. the link to
> DTV antenna install guidelines provided by the Digital Broadcasting
> Australia (association)..

There is nothing missing Tim this is not a quote, I personally know
what they are running as I was involved in the DVB versus ATSC testing
in Australia before the decision to go COFDM DVB was made.
I had the opportunity to see ATSC in action against ATSC in Australia
as I was responsible for the transmitter used for the tests, it was
used for BOTH ATSC and COFDM and as such there was no question about
different types of transmitter, and as you may be aware the
requirements for a COFDM transmitter are more stringent than for
ATSC.I subsequently was involved in the installation, commissioning
and setup of the COFDM DTV transmitters used in the capital cities by
the commercial networks, and the training of the operators
in each state.
I know what I set the modulators for and I can assure you
that the rate is exactly 23.052768 Mb/s or 19.353 Mb/s not some
21.3Mb/s which is a rate not available on any 6,7 or 8Mhz channel
using COFDM and as such is not used in Australia (or anywhere else for
that matter).

For your information the stations are running the following profiles:

ABC
T 7MHz 3/4 NONE QAM64 8k 1/16 NONE
Seven
T 7MHz 2/3 NONE QAM64 8k 1/8 NONE
Nine
T 7MHz 3/4 NONE QAM64 8k 1/16 NONE
Ten
T 7MHz 3/4 NONE QAM64 8k 1/16 NONE
SBS
T 7MHz 2/3 NONE QAM64 8k 1/8 NONE

There are also some datacasting transmissions that use very low data
rates
on each service, but still use the "standard" transmission profile
above.
In Sydney these transmissions cover the metropolitan area using an 800
watt transmitter.



> >> Notice, that they recommend the minimum signal Margin should be 9dB
> >> and the preferred Margin is >20dB!!! (Impulse noise is such a bitch.)
> >>
> >> Note: That's MARGIN !!! not overall S/N.. Margin starts out at a
> >> threshold where you can already receive and decode the DTV signal (17
> >> to 21dB of S/N). Recommended Margin adds another 9 to 20dB to that
> >> number to reduce COFDM's impulse noise issues.

Yes this is desirable but the system will work without these margins.
What is more of a concern is not the C/N received but the MER of the
transmitter as if it has a bad MER no amount of C/N will give
acceptable results. IE if it is less than 19 dB no matter how strong
the signal it
will not decode.


> >The impulse noise issue is an issue in all systems, but is not a
> >problem with current COFDM boxes.
>
> Not really.. Impulse noise doesn't bother 8VSB nearly as much.
> ( You loose a few packets.. maybe.. one would have a hard time
> finding the display anomalies. )

Not what I have seen when watching ATSC.
>

>
> P.S Why did you forget to quote the link?? Embarrassed??

No, it is irrelevant as you have also left out much of the other
information
contained in the linkthat is pro-COFDM.
>
> Check out the DTV antenna install guidelines in the Australia..
>http://www.dba.org.au/uploads/templates/files/DBA_Insta...
>
> >> Net result COFDM Needs 25 to 40dB of S/N to receive a reliable
> >> COFDM signal.

This is total rubbish.

Modern set-tops operate with 19dB or less with no margin.
We are not talking about "over the horizon" reception over vast
distances, we are talking about relatively short distances to the edge
of the service area of a station. In fact stations are not allowed to
put substantial signals outside their service area as defined by the
government.
The service areas were defined by analogue transmissions and the
digital transmissions (usually on adjacent channels actually go
further than the analogue PAL signal is watchable.
One needs more than 19dB to decode, and much lower margins than 9dB
work well in practice.
If you read the link you will find it basically says if you have an
antenna that works on analogue it will be OK for digital.
There is actually a much higher C/N required for a good PAL analogue
picture
than is required for COFDM.


> > COFDM is an inferior digital broadcast
> >> format and should not be confused with something practical.
> >
> >What is practical? Surely you don't suggest that ATSC 8VSB is an
> >alternative for anywhere?
>
> It works a whole lot better than the alternatives.

Be real! Nowhere else is ATSC being considered as a usable system
and no-one would setup a new system using it.
You would be better off dumping ATSC and going COFDM.
But let's face it you are stuck with it and you have to make it work,
and we are happy with COFDM.
>
> Europe and Australia would be better off dumping COFDM and
> switching to 8VSB. Instead you'll probably be sentenced to low def
> programming for a couple more decades.. Ouch...

I cannot see why you insist that SD is all we get.

We transmit a data rate of about 20Mb/s at least. If we use it for 5
SD
channels, 1 HD channel or a combination of both it is still the same
signal.
It dosn't change with a change in the data rate of the HD signal so it
is totally irrelevant what the service data rates are. the
"Receivability" of the COFDM signal is exactly the same whatever the
makeup of the stream, and
ststions are running HD now.
If you have an issue with what is HD, ED or SD this has nothing to do
with
the transmission method.
>
> >
> >It is possible to receive reliable signals in parts of the the Sydney
> >area on UHF from Wollongong and Newcastle transmissions on a simple
> >whip antenna (No outside antenna needed) of the 23Mb/s COFDM Muxs from
> >these adgacent service areas. Newcastle is about 100Km north and the
> >Wollongong
> >transmission site about 100Km south of Sydney.
> >
> >I have a "Hi-Top" COFDM portable which is similar to the small DVD
> >players with a fold-up 7 inch LCD screen and runs on a 12 volt battery.
> >I can use it virtually anywhere in Sydney and even in a moving vehicle
> >on its whip antenna.
> >>
The whip i use is not a fancy one, its simply a quarter wave steel
tape antenna that was originally supplied with a VHF radio mic.
Not exactly Hi-tech but it works well on both VHF and UHF.

> >> B.T.W.. From by surfing of Australia's DTV forums.. All but one
> >> network(Nine) has abandoned ALL HDTV programming. They sticking with
> >> 576p in order to gain a few more dB's of S/N ratio in an effort to
> >> overcome COFDM's near fatal weakness.
> >
Again More Rubbish!

I repeat, THERE IS NO ADVANTAGE AS THIS IS A SERVICE DATA RATE IN A
MUXED STREAM
THAT IS STILL AT SOME 19-23 MB/s (more than you get with ATSC) and
dosn't change at all with stream content.

It is possible to run COFDM digital at QPSK, 1/2, 1/8. as is done with
wireless camera systems at about 6Mb/s with a much lower C/N
requirement and this has been tested in Australia with enormous
coverage even to mobile receivers, but this is NOT done by the
broadcasters here. They MUST run a high data rate because the
legislation states that they must run a digital HD programme, an SD
digital programme, and at present an analogue programme. These MUST
all be the same programming so eithr they downconvert the HD to SD for
the SD service, or up-convert the SD to quasi HD as they are required
to do by law.
This is why the quality of some services varies dramatically from time
to time.
>
> I've posted the link on other posts..
> http://www.dtvforum.info/lofiversion/index.php/t15077.h...
> ABC . HDTV, R.I.P... was 1080i50(x1920) is now 576p(x720)..
>
The ABC and SBS are allowed as Government stations to run simultaneous
multi sd services if they desire. The ABC has started ABC2 a second SD
service this week in their stream and this is what I think you have
misconstrued as being a departure from HD.
>
> From what I hear SD is consuming 6Mb/s .. which is somewhat high..
> Especially since the frame SD refresh rate is somewhat lower than
> ours .. 50 Hz(v 60Hz). Sounds like they're upping the FEC in an
> effort compensate for the modulation scheme.

AGAIN THE DATARATE OF A SERVICE DOSNT CHANGE THE TRANSMISION
PARAMETERS.
The FEC is the same whatever the service is in the stream (unless they
run
heirarchial modulation which does lose a substantial amount of the
available datarates in a 7 Mhz channel).
>
> B.T.W. My local PBS(H)DTB station has no problem running a
> High def 1080i60 channel along with two low def's 480i all at the same
> time.

Yes and they are running it all in the less available datarate on ATSC
than we have here on all COFDM transmissions.
>

>
> Doesn't sound like it.. TEN is now broadcasting 576p at a 8.5Mb/s
> data rate. (Their new HD standard)..

See above....


> >Far from giving up on HD the stations are in fact running much of
> >their programming in HD. Most prime time shows are running in HD
> >as well as simultaneous SD.
>
> Now that a minister has redefined EDTV 576p25(x720) to be HD. I'm
> not surprised by your statements. see
> http://www.dba.org.au/index.asp?sectionID=15
>
> In the US, anything less than 720p(x1280) is not considered to be
> hi-def..
> http://support.gateway.com/s/CsmrEltrncs/DigitalTV/Shar...
>
> >As they are running so much HD programming they have stopped running
> >HD promo loops as they feel that there is no need to promote by loops
> >of "Pretty Pictures" any more. There are now so many viewers of HD
>
> http://www.dba.org.au/newsletter/IB-FebMar05-full.asp#P...
>
> "By end of 2004 the estimated number of digital television set top
> box receivers and integrated digital tv sets in Australian homes was
> 658,000, with more than 400,000 units sold in the 12 months to
> December 2004"
>
> Only 650K.. tsk..tsk.. another whopper of a lie..
> (A vast majority of them can't decode anything over 576p).

There was no suggestion that they were HD boxes. In fact the
government here
insisted that "cheap SD only boxes" would be available so that when
the analogue PAL transmissions cease that SD digital would be
available to all. This was a deliberate decision and is the basis of
the "Triplecast SD plus HD plus analogue
transmissions" were legislated.
>
>
> >with
> >low cost (approx US$200) HD settop boxes now freely available that
> >they are no longer needed.
>
> Sound's like this is another BM clone..
> Declare red(ED) is green(HD) and then claim how all the green(HD) +
> red(ED) prices have dropped.
>
>
> None the less.. we in the US consider anything less than 720p(x1280)
> to be less than high def.. Last time I checked, Australian
> 720p/1080i receivers still run in the 500$ range..

I have bought a "Acoustic Research" HD box with all 1080i, 576P and SD
outputs available for A$360.00 (about US$270) and it works flawlessly.
There are some which are sub US$200 available here as well as numerous
HD PC cards.

It seeems that you are straying a long way from the original question
re Digital TV in New Zealand.
The makeup of the stream and what is SD, ED, or HD has nothing to do
with the transmission method as both ATSC and DVB COFDM give
essentially the same data rates.
The simple answer is that with a low power transmitter they can
impliment DTV in a city like Auckland on COFDM easily.
Anonymous
March 4, 2005 12:09:52 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On Thu, 3 Mar 2005 11:31:53 -0500, "David" <davey@home.com> wrote:

>Yes, it is interesting- but I guess where there are so many complaints about
>switching a ~25 watt bulb in a partially enclosed metal enclosure (a
>refrigerator) causing impulse noise and picture/sound loss, I'm not
>surprised.

It sounds as if there are problems with inadequate STB power supply
filtering :-).

Paul
Anonymous
March 4, 2005 12:09:53 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Paul Keinanen" <keinanen@sci.fi> wrote in message
news:b41g211recq13upeq8hn3pgerl7evnctl0@4ax.com...
> On Thu, 3 Mar 2005 11:31:53 -0500, "David" <davey@home.com> wrote:
>
> >Yes, it is interesting- but I guess where there are so many complaints
about
> >switching a ~25 watt bulb in a partially enclosed metal enclosure (a
> >refrigerator) causing impulse noise and picture/sound loss, I'm not
> >surprised.
>
> It sounds as if there are problems with inadequate STB power supply
> filtering :-).
>
> Paul

Paul,

This kind of a.c. line noise is unlikely to affect most modern video power
supplies. Most STBs and TVs use a switching PS where the incoming a.c. is
rectified and filtered like a conventional supply, then the d.c. is switched
at a frequency in the kHz range though a converter transformer, then in the
secondary it is rectified again using fast recovery diodes and multiple
filter caps. Very little noise riding the a.c. line makes it through the
switching supply. More common is for it to enter through other devices at
the signal level, such as power insertion or cheap power supplies (wall
warts) on RF amplifiers, through more conventional power supplies in audio
amplifiers, or through ground loops.

Leonard
Anonymous
March 4, 2005 12:42:14 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Leonard Caillouet wrote:

>
>
> Paul,
>
> This kind of a.c. line noise is unlikely to affect most modern video power
> supplies.

Right. Basically, it comes in over the air.

Where I live there is a terrible power line noise problem,
which comes from the 35,000 volt line two houses down from mine.

It would require a large antenna to make DTV work with
a 2 kW channel 3 transmitter, like a ten element Yagi.
Our Channel 3 analog is 11 miles away. I could pick up
a UHF channel 41 DTV station 16 miles away on a paper clip
when it was 2 kW on a 1300 foot tower. This is 8VSB of course.
When it was on a 200 foot up antenna on that same tower it took
a real antenna where I live.

Doug McDonald
Anonymous
March 4, 2005 1:23:28 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On 4 Mar 2005 05:27:37 -0800, 100246.2055@compuserve.com (Ian
Mackenzie) wrote:

>Tim Keating wrote more rubbish.....getting further off track.

snip.... A COFDM troll's attempt debate without a being able to
make rational decisions. (I.E. Simply declaring all authoritative
references as rubbish).

There is little to debate when one's opposite demonstrate's
irrational behavior.
Anonymous
March 4, 2005 2:01:28 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On 4 Mar 2005 05:27:37 -0800, 100246.2055@compuserve.com (Ian
Mackenzie) wrote:

>Tim Keating wrote more rubbish.....getting further off track.

snip.... A COFDM troll's attempt to debate without a being able to
make rational decisions. (I.E. Simply declaring all authoritative
references as rubbish).

There is little to debate when one's opposite demonstrate's
irrational behavior.
Anonymous
March 4, 2005 4:33:45 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Tim Keating <NotForJunkEmail@directinternet11.com1> wrote in message news:<sh1h21hiut17br6omf8ohv32o53bljr6j6@4ax.com>...
> On 4 Mar 2005 05:27:37 -0800, 100246.2055@compuserve.com (Ian
> Mackenzie) wrote:
>
> >Tim Keating wrote more rubbish.....getting further off track.
>
> snip.... A COFDM troll's attempt to debate without a being able to
> make rational decisions. (I.E. Simply declaring all authoritative
> references as rubbish).
>
> There is little to debate when one's opposite demonstrate's
> irrational behavior.


Tim,
You made some very wrong and inaccurate statements when you beleived
what some others mistakedly wrote in newsgroups. Not an accurate place
to get the truth.
When given the actual facts calling me a "COFDM Troll" dson't change
the fact
yoiu were wrong.

Your response Tim is:
Don't confuse me with the facts.... my mind's made up already!
Anonymous
March 4, 2005 4:47:47 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

David wrote:
> Standard digital [non-high definition] is just easier for everyone all
> around. Broadcasters and customers.

I guess I'm having a hard time understanding how reducing definition
reduces interference/noise problems.

Or does the NZ system actually reduce transmitted data rate (and maybe
somehow increase the number of "check bits" in the FEC?) when the higher
rate is not necessary for transmission of high-definition programs?

I mean, here in the States if I transmit a 480i signal instead of 1080i
the overall bit rate of what hits the transmitter (and what the receiver
must decode) doesn't change. It just gets stuffed with null packets...
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com
Anonymous
March 4, 2005 4:47:48 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

On Fri, 04 Mar 2005 13:47:47 GMT, Doug Smith W9WI
<w9wi@invalid.invalid> wrote:

>David wrote:
>> Standard digital [non-high definition] is just easier for everyone all
>> around. Broadcasters and customers.
>
>I guess I'm having a hard time understanding how reducing definition
>reduces interference/noise problems.

COFDM's has the ability to use certain frequency band centered
carriers so that the minimum S/N is a few dB lower than what would be
needed if one uses the entire payload of the band. (hi-def)

This part of their claim for mobile reception.. (I.E. Use high
reliability carriers for mobile/standard def reception).

Additionally, it gets more reliable as they add more error
correction bits.. (I.E. They're able to correct for more dropped bits
do to locally(near receiver) generated impulse interference.)

>
>Or does the NZ system actually reduce transmitted data rate (and maybe
>somehow increase the number of "check bits" in the FEC?) when the higher
>rate is not necessary for transmission of high-definition programs?

NZ doesn't have an OTA Digital system yet...
They have yet to make a decision.. I.E. Watching and waiting.

>I mean, here in the States if I transmit a 480i signal instead of 1080i
>the overall bit rate of what hits the transmitter (and what the receiver
>must decode) doesn't change. It just gets stuffed with null packets...

That is correct.. We in the U.S. use a constant bit rate for all
8VSB broadcasts. [5.38Mhz used out of 6Mhz channel assignment,
21,520,000bps raw(Data+FEC), 19,280,000bps(Error corrected Payload)] .
If you can receive the signal , you have everything you need for
Hi-def reception (if it is available).
Anonymous
March 4, 2005 8:21:33 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Tim Keating wrote:
> On Fri, 04 Mar 2005 13:47:47 GMT, Doug Smith W9WI
> <w9wi@invalid.invalid> wrote:
>
>
>>David wrote:
>>
>>>Standard digital [non-high definition] is just easier for everyone all around. Broadcasters and customers.
>>
>>I guess I'm having a hard time understanding how reducing definition reduces interference/noise problems.
>
>
> COFDM's has the ability to use certain frequency band centered carriers so that the minimum S/N is a few dB lower than what would be
> needed if one uses the entire payload of the band. (hi-def) This part of their claim for mobile reception.. (I.E. Use high reliability carriers for mobile/standard def reception).
>
> Additionally, it gets more reliable as they add more error correction bits.. (I.E. They're able to correct for more dropped bits
> do to locally(near receiver) generated impulse interference.)


Again all true except for the implication that COFDM HAS to transmit at
a lower bit rate than 8-VSB to achieve equal to or better reception.
Again but not exclusively (it can be repeated anytime) COFDM as
demonstrated by Sinclair in 2000 was able to work MOBILE at a higher
datarate, 19.76 Mbps, than 8-VSB was able to work fixed, 19.34 Mbps.

This is a big deal. COFDM works/worked mobile when 8-VSB proponents in
the SAME room DECLINED to ATTEMPT to move their SILVER SENSOR
DIRECTIONAL antenna to the witness table. To hoots of laughter from the
all in the room.

A two dollar antenna beat out a directional Silver Sensor that had to be
positioned just so, taped to the window sill.

COFDM does have the option to go to MANY more robust modes that do
sacrifice bits for robustness but at the same time it can trounce 8-VSB
at the ONLY bit rate 8-VSB can do.
>
>
>>Or does the NZ system actually reduce transmitted data rate (and maybe somehow increase the number of "check bits" in the FEC?) when the higher
>>rate is not necessary for transmission of high-definition programs?
>
>
> NZ doesn't have an OTA Digital system yet... They have yet to make a decision.. I.E. Watching and waiting.

They have tested or demonstrated DVB-T. The government has basically
left it in the hands of the TV industry there. When they have a business
plan they will go forward. It will most likely be DVB-T but since they
have not finalized their plans they could consider something new like
DMB-T or ISDB-T. Certainly will not consider 8-VSB.

Bob Miller
>
>
>>I mean, here in the States if I transmit a 480i signal instead of 1080i the overall bit rate of what hits the transmitter (and what the receiver
>>must decode) doesn't change. It just gets stuffed with null packets...
>
>
> That is correct.. We in the U.S. use a constant bit rate for all 8VSB broadcasts. [5.38Mhz used out of 6Mhz channel assignment,
> 21,520,000bps raw(Data+FEC), 19,280,000bps(Error corrected Payload)] .
> If you can receive the signal , you have everything you need for Hi-def reception (if it is available).
Anonymous
March 4, 2005 8:21:34 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Bob Miller wrote:


> Again all true except for the implication that COFDM HAS to transmit at
> a lower bit rate than 8-VSB to achieve equal to or better reception.


That is incorrect. The current COFDM systems MUST repeat MUST use a
lower bitrate mode compared to 8-VSB in order to achieve the same needed
C/N ratio. This is simply indisputeable.

Doug McDonald
Anonymous
March 4, 2005 11:31:33 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Doug McDonald wrote:
> Bob Miller wrote:
>
>
>> Again all true except for the implication that COFDM HAS to transmit
>> at a lower bit rate than 8-VSB to achieve equal to or better reception.
>
>
>
> That is incorrect. The current COFDM systems MUST repeat MUST use a
> lower bitrate mode compared to 8-VSB in order to achieve the same needed
> C/N ratio. This is simply indisputeable.
>
> Doug McDonald

Indisputable except in the real world where COFDM DVB-T is able and was
able to deliver 1080i HD at 19.76 Mbps mobile at the Congressional
hearings in 2000.
While 8-VSB was and is stuck at 19.34 Mbps and needs a lot of help and
luck even then. What 8-VSB needs is to lower its bit rate to a more
comfortable 8 Mbps and do some E-VSB with a little bit of robustness so
that people can at least get an SD signal near 8-VSB MEGAWATT transmitters.

That is indisputable!!!! The rest is just BS.

Bob Miller
Anonymous
March 4, 2005 11:31:34 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Bob Miller wrote:

>>
>>
>> That is incorrect. The current COFDM systems MUST repeat MUST use a
>> lower bitrate mode compared to 8-VSB in order to achieve the same
>> needed C/N ratio. This is simply indisputeable.
>>
>> Doug McDonald
>
>
> Indisputable except in the real world where COFDM DVB-T is able and was
> able to deliver 1080i HD at 19.76 Mbps mobile at the Congressional
> hearings in 2000.


But not at a distance where it was limited by C/N ratio.

The Congressional Hearings were not at the edge of the
coverage area, nor otherwise power limited. Most places
where coverage is in question are power limited. This is the
ultimate reason the USA chose 8-VSB over COFDM.

You keep trying to answer facts with sales blurbs.

Doug McDonald



Doug McDonald
March 5, 2005 11:24:58 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Ian Mackenzie" <100246.2055@compuserve.com> wrote in message
news:27f1d4f3.0503040527.54ae12c4@posting.google.com...
> Tim Keating wrote more rubbish.....getting further off track.
>
> I said:
>> >The transmissions in Australian capital cities run 3.5Kw transmitter
>> >power and cover the metropolitan areas with no trouble.
>> >In most areas where analogue is unwatchable the digital signals are
>> >perfect.
>> >The stations have 5Kw transmitters but there is no need to run at
>> >their full power to give full coverage of their service areas.
>
> I stand by those statements.
>> >
>>
>> Hmmm.. something missing from this quote.. ... Oh yeah.. the link to
>> DTV antenna install guidelines provided by the Digital Broadcasting
>> Australia (association)..
>
> There is nothing missing Tim this is not a quote, I personally know
> what they are running as I was involved in the DVB versus ATSC testing
> in Australia before the decision to go COFDM DVB was made.
> I had the opportunity to see ATSC in action against ATSC in Australia
> as I was responsible for the transmitter used for the tests, it was
> used for BOTH ATSC and COFDM and as such there was no question about
> different types of transmitter, and as you may be aware the
> requirements for a COFDM transmitter are more stringent than for
> ATSC.I subsequently was involved in the installation, commissioning
> and setup of the COFDM DTV transmitters used in the capital cities by
> the commercial networks, and the training of the operators
> in each state.
> I know what I set the modulators for and I can assure you
> that the rate is exactly 23.052768 Mb/s or 19.353 Mb/s not some
> 21.3Mb/s which is a rate not available on any 6,7 or 8Mhz channel
> using COFDM and as such is not used in Australia (or anywhere else for
> that matter).
>
> For your information the stations are running the following profiles:
>
> ABC
> T 7MHz 3/4 NONE QAM64 8k 1/16 NONE
> Seven
> T 7MHz 2/3 NONE QAM64 8k 1/8 NONE
> Nine
> T 7MHz 3/4 NONE QAM64 8k 1/16 NONE
> Ten
> T 7MHz 3/4 NONE QAM64 8k 1/16 NONE
> SBS
> T 7MHz 2/3 NONE QAM64 8k 1/8 NONE
>
> There are also some datacasting transmissions that use very low data
> rates
> on each service, but still use the "standard" transmission profile
> above.
> In Sydney these transmissions cover the metropolitan area using an 800
> watt transmitter.
>
I agree with your comments but the 800 watt transmitter ?
The 4 VHF stations have an ERP of 50kw (some may be temporarily limited to
30kw due to co-channel interence) . A 5kw transmitter is used to achieve
this power. The 2 UHF stations have an erp of 200kw and I assume that 7.5kw
transmitters would be used.

Frank
Anonymous
March 5, 2005 2:18:08 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Bob Miller wrote:
> In OZ they have to do HDTV and
> they have decided that 576P is HD.

Hey BOB, we can decide right here that HD is 480i!!! So what? These are
just words, not reality! When you see REAL HD (oops, forgot you don't
own an HDTV) you KNOW it's HD. 576P aint no HD my son. If OZ feels
comfortable in lowering the bar for what HD really is, that's fine with
me (I for one would NEVER invest in an HDTV if that was the definition
of HD in the U.S.), but thank God my country didn't do that!!!!

>The fact is that in any given frame
> 576 is more than 540 which is what 1080i is. If nothing else the two
are
> not that far apart.

You are one scary dude BOB. If you 'really' believe that 540p is the
same as 1080i, you are far far more ignorant than I would have ever
believed. But of course, if lowering the bar for HD fits more neatly
into your business plan at the expense of screwing everyone else who is
really interested in TRUE HD, and deliberately deceiving people like
you typically do for the furthering of your own objectives is what
you're REALLY doing.....well, THAT I can believe.

BTW BOB, you've never answered my question about what you expect to
gain by trying to pull the wool over a few people's eyes on an obscure
ng? You spend countless hours here, weaving the same lie day after day,
hour after hour. What do you expect to gain? I'll never understand
this, please bring me up to speed on this.
Anonymous
March 5, 2005 2:18:22 PM

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Bob Miller wrote:
> In OZ they have to do HDTV and
> they have decided that 576P is HD.

Hey BOB, we can decide right here that HD is 480i!!! So what? These are
just words, not reality! When you see REAL HD (oops, forgot you don't
own an HDTV) you KNOW it's HD. 576P aint no HD my son. If OZ feels
comfortable in lowering the bar for what HD really is, that's fine with
me (I for one would NEVER invest in an HDTV if that was the definition
of HD in the U.S.), but thank God my country didn't do that!!!!

>The fact is that in any given frame
> 576 is more than 540 which is what 1080i is. If nothing else the two
are
> not that far apart.

You are one scary dude BOB. If you 'really' believe that 540p is the
same as 1080i, you are far far more ignorant than I would have ever
believed. But of course, if lowering the bar for HD fits more neatly
into your business plan at the expense of screwing everyone else who is
really interested in TRUE HD, and deliberately deceiving people like
you typically do for the furthering of your own objectives is what
you're REALLY doing.....well, THAT I can believe.

BTW BOB, you've never answered my question about what you expect to
gain by trying to pull the wool over a few people's eyes on an obscure
ng? You spend countless hours here, weaving the same lie day after day,
hour after hour. What do you expect to gain? I'll never understand
this, please bring me up to speed on this.
Anonymous
March 5, 2005 8:29:59 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Frank" <frankxxx@nowhere.com> wrote in message news:<4228d22d$0$11363$afc38c87@news.optusnet.com.au>...

> I agree with your comments but the 800 watt transmitter ?
> The 4 VHF stations have an ERP of 50kw (some may be temporarily limited to
> 30kw due to co-channel interence) . A 5kw transmitter is used to achieve
> this power. The 2 UHF stations have an erp of 200kw and I assume that 7.5kw
> transmitters would be used.
>
> Frank

The "datacasting" service in Sydney is running from the BA site at
Gore Hill
(The old Channel 2 ABC site) on UHF channel 34. The power of the
transmitter IS 800 watts average in comparison to the SBS analogue
service using a 30KW peak transmitter into the same antenna.

The service gives good coverage of the Sydney area and goes to show
that
large powers are not required for COFDM. There are incidentally no SFN
transmitters on the service.
March 6, 2005 8:07:48 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Max Power" <mikehack@u.washington.edu> wrote in message
news:D 09620$8g4$1@gnus01.u.washington.edu...
> I agree with the analysis of your posted links.
> However, without actually starting transmissions in AUK, WEL and CHCH the
> ball will never get rolling.
>
> I don't see a speedy HDTV transition in towns that are less than 30,000
> people.
> However, due to NZ hilly terrain it is easy for one local commercial TV
> station to switch to HD -- like TV4.
> The local TV4 HD repeater could then carry TV1 + (TV2/TV3) in its bundle.
>
Fat chance we'll see HD out of the non-state-funded Stations ie TV3 and TV4
for a **VERY** long time. These are commercial businesses owned by overseas
people (currently Canwest +shareholders), unlike TV1 and TV2 that have a
huge pipe flowing tax payers' cash to them (to pay for their $800,000 salary
newsreaders) from Wellington (Govt) plus the $ they take in advertising.

Fatter chance still therefore that we'll ever see TV3/TV4 since they are a
total threat to TVNZ anything TVNZ does ...and its equally likely that
TV3/TV4 would never give rites to their opposition to carry their program in
any bundle delivery arrangement that TVNZ initiates... even though the
material will be standard def.

Interesting too that sales of new TV cameras worldwide tend to be virtually
always HD for Northern Hemisphere while in the Southern they continue to
specify SD. (Manufactures are the force here though and stateing that in the
next couple of years they will make only HD cams.) A camera will last...
5~10 yrs so i guess local material will be shot in SD only ... maybe the odd
foray to SD16:9 for *some* productions....

Pete
March 6, 2005 3:45:00 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Ian Mackenzie" <100246.2055@compuserve.com> wrote in message
news:27f1d4f3.0503051729.65423d4e@posting.google.com...
> "Frank" <frankxxx@nowhere.com> wrote in message
> news:<4228d22d$0$11363$afc38c87@news.optusnet.com.au>...
> The "datacasting" service in Sydney is running from the BA site at
> Gore Hill
> (The old Channel 2 ABC site) on UHF channel 34. The power of the
> transmitter IS 800 watts average in comparison to the SBS analogue
> service using a 30KW peak transmitter into the same antenna.
>
> The service gives good coverage of the Sydney area and goes to show
> that
> large powers are not required for COFDM. There are incidentally no SFN
> transmitters on the service.

Sorry, I mis read you post. I thought you meant that they all used 800w
transmitters.
Do you know what the ERP of the datacasting channel is ? I am 14km from it
and receive it using an a basic indoor antenna with no problems at all.

Frank
Anonymous
March 6, 2005 3:45:01 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

"Frank" <frankxxx@nowhere.com> wrote in message news:<422a60a1$0$12026$afc38c87@news.optusnet.com.au>...
> "Ian Mackenzie" <100246.2055@compuserve.com> wrote in message
> news:27f1d4f3.0503051729.65423d4e@posting.google.com...
> > "Frank" <frankxxx@nowhere.com> wrote in message
> > news:<4228d22d$0$11363$afc38c87@news.optusnet.com.au>...
> > The "datacasting" service in Sydney is running from the BA site at
> > Gore Hill
> > (The old Channel 2 ABC site) on UHF channel 34. The power of the
> > transmitter IS 800 watts average in comparison to the SBS analogue
> > service using a 30KW peak transmitter into the same antenna.
> >
> > The service gives good coverage of the Sydney area and goes to show
> > that
> > large powers are not required for COFDM. There are incidentally no SFN
> > transmitters on the service.
>
> Sorry, I mis read you post. I thought you meant that they all used 800w
> transmitters.
> Do you know what the ERP of the datacasting channel is ? I am 14km from it
> and receive it using an a basic indoor antenna with no problems at all.
>
> Frank


The maximum they are allowed to transmit at present is 20KW as there are other
services on the channel in Newcastle, Wollongong and Nowra.

I think they are running about 15KW EIRP actually.

I receive it on a whip in Belrose.
Anonymous
March 6, 2005 8:04:22 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Frank wrote:

>>(The old Channel 2 ABC site) on UHF channel 34. The power of the
>>transmitter IS 800 watts average in comparison to the SBS analogue
>>service using a 30KW peak transmitter into the same antenna.
>>
>>The service gives good coverage of the Sydney area and goes to show
>>that
>>large powers are not required for COFDM. There are incidentally no SFN
>>transmitters on the service.
>
>
> Sorry, I mis read you post. I thought you meant that they all used 800w
> transmitters.
> Do you know what the ERP of the datacasting channel is ? I am 14km from it
> and receive it using an a basic indoor antenna with no problems at all.


14 km is only 8.5 miles. That's exceedingly unimpressive. When
one of our stations (a channel 41) was at low power (1.5 kW ERP ....
not transmitter power) and at 180 feet up their tower I received it
with no problem with a simple twin-bowtie indoor antenna. This
is 26 kM from the transmitter. Oh yes ... that's with the
antenna pointing the wrong way.

This, of course, is 8-VSB.

Doug McDonald
Anonymous
March 7, 2005 6:57:23 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Doug McDonald <mcdonald@SnPoAM_scs.uiuc.edu> wrote

> 14 km is only 8.5 miles. That's exceedingly unimpressive. When
> one of our stations (a channel 41) was at low power (1.5 kW ERP ....
> not transmitter power) and at 180 feet up their tower I received it
> with no problem with a simple twin-bowtie indoor antenna. This
> is 26 kM from the transmitter. Oh yes ... that's with the
> antenna pointing the wrong way.
>
> This, of course, is 8-VSB.
>
> Doug McDonald

Also pretty unimpressive Doug.

We can get 40 Km on 2.5Ghz using 3 watts and a 4dB gain antenna.

But of course thats COFDM.
Anonymous
March 7, 2005 11:35:45 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Ian Mackenzie wrote:

> Doug McDonald <mcdonald@SnPoAM_scs.uiuc.edu> wrote
>
>
>>14 km is only 8.5 miles. That's exceedingly unimpressive. When
>>one of our stations (a channel 41) was at low power (1.5 kW ERP ....
>>not transmitter power) and at 180 feet up their tower I received it
>>with no problem with a simple twin-bowtie indoor antenna. This
>>is 26 kM from the transmitter. Oh yes ... that's with the
>>antenna pointing the wrong way.
>>
>>This, of course, is 8-VSB.
>>
>>Doug McDonald
>
>
> Also pretty unimpressive Doug.
>
> We can get 40 Km on 2.5Ghz using 3 watts and a 4dB gain antenna.
>
> But of course thats COFDM.

But is it with the 4 dB gain antenna pointing the wrong way,
and the transmitter exactly at the radio horizon?

Doug McDonald
Anonymous
March 7, 2005 3:23:18 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Ian Mackenzie wrote:
> Doug McDonald <mcdonald@SnPoAM_scs.uiuc.edu> wrote
>
>
>>14 km is only 8.5 miles. That's exceedingly unimpressive. When
>>one of our stations (a channel 41) was at low power (1.5 kW ERP ....
>>not transmitter power) and at 180 feet up their tower I received it
>>with no problem with a simple twin-bowtie indoor antenna. This
>>is 26 kM from the transmitter. Oh yes ... that's with the
>>antenna pointing the wrong way.
>>
>>This, of course, is 8-VSB.
>>
>>Doug McDonald
>
>
> Also pretty unimpressive Doug.
>
> We can get 40 Km on 2.5Ghz using 3 watts and a 4dB gain antenna.
>
> But of course thats COFDM.

If you want to be really really impressed come to New York, I hear they
have similar problems all over, but in New York you can see the Empire
State Building in all its glory only blocks away with the top encrusted
with antennas some of which are buzzing with MEGAWATTS of power to
deliver 8-VSB which is NOT receivable as little as 8 blocks away with
clear line of sight.

Now that is impressive!! The military could use 8-VSB to block enemy RF
emissions. Just broadcast 8-VSB on any battlefield and eliminate the
possibility of receiving anything at all by anyone. Of course you could
receive that 8-VSB emission on another battlefield at 99 miles distant
with a tweaked directional antenna if the info is of any use over there.

Really impressive though.

Bob Miller
Anonymous
March 7, 2005 4:44:23 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Doug McDonald <mcdonald@SnPoAM_scs.uiuc.edu> wrote in message news:<d0hos1$29o$1@news.ks.uiuc.edu>...
> Ian Mackenzie wrote:
>
> > Doug McDonald <mcdonald@SnPoAM_scs.uiuc.edu> wrote
> >
> >
> >>14 km is only 8.5 miles. That's exceedingly unimpressive. When
> >>one of our stations (a channel 41) was at low power (1.5 kW ERP ....
> >>not transmitter power) and at 180 feet up their tower I received it
> >>with no problem with a simple twin-bowtie indoor antenna. This
> >>is 26 kM from the transmitter. Oh yes ... that's with the
> >>antenna pointing the wrong way.
> >>
> >>This, of course, is 8-VSB.
> >>
> >>Doug McDonald
> >
> >
> > Also pretty unimpressive Doug.
> >
> > We can get 40 Km on 2.5Ghz using 3 watts and a 4dB gain antenna.
> >
> > But of course thats COFDM.
>
> But is it with the 4 dB gain antenna pointing the wrong way,
> and the transmitter exactly at the radio horizon?
>
> Doug McDonald

Yes Doug.

The antenna is an Omni so it points all ways at once, get all ghosts
and reflections and 40 Km from ground level is close enough to the
horizon.

The point is it wouldn't work with 8VSB.
Anonymous
March 7, 2005 7:50:23 PM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Ian Mackenzie wrote:

>
> The antenna is an Omni so it points all ways at once, get all ghosts
> and reflections and 40 Km from ground level is close enough to the
> horizon.
>
> The point is it wouldn't work with 8VSB.

So choosing the wrong antenna is 8-VSB's fault? Give me a break. Not
very many people get good reception of NTSC on omni-directional antenna.

Matthew
Anonymous
March 8, 2005 1:13:47 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Matthew L. Martin wrote:
> Ian Mackenzie wrote:
>
>>
>> The antenna is an Omni so it points all ways at once, get all ghosts
>> and reflections and 40 Km from ground level is close enough to the
>> horizon.
>>
>> The point is it wouldn't work with 8VSB.
>
>
> So choosing the wrong antenna is 8-VSB's fault? Give me a break. Not
> very many people get good reception of NTSC on omni-directional antenna.
>
> Matthew

No 8-VSB can not handle multipath so you need a directional antenna in
the presence of multipath.

The fact that NTSC and 8-VSB share the same problems of receptions says
little for 8-VSB.

COFDM was designed for multipath that is why an omni antenna is better,
a directional antenna would screen out some of the multipath signals
that COFDM can use.

Bob Miller
Anonymous
March 8, 2005 1:13:48 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast,alt.usenet.kook (More info?)

Bob Miller wrote:
> Matthew L. Martin wrote:
>
>> Ian Mackenzie wrote:
>>
>>>
>>> The antenna is an Omni so it points all ways at once, get all ghosts
>>> and reflections and 40 Km from ground level is close enough to the
>>> horizon.
>>>
>>> The point is it wouldn't work with 8VSB.
>>
>>
>>
>> So choosing the wrong antenna is 8-VSB's fault? Give me a break. Not
>> very many people get good reception of NTSC on omni-directional antenna.
>>
>> Matthew
>
>
> No 8-VSB can not handle multipath so you need a directional antenna in
> the presence of multipath.

No true, you moron. There are many reasons to use a directional antenna.
When was the last time you saw a point to point microwave system use an
omni.

> The fact that NTSC and 8-VSB share the same problems of receptions says
> little for 8-VSB.

Read what was written, not what you want to see.

> COFDM was designed for multipath that is why an omni antenna is better,
> a directional antenna would screen out some of the multipath signals
> that COFDM can use.

Until there is a burst of impulse noise.

Matthew

--
Thermodynamics and/or Golf for dummies: There is a game
You can't win
You can't break even
You can't get out of the game
Anonymous
March 8, 2005 1:13:48 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

Bob Miller wrote:

>
> No 8-VSB can not handle multipath so you need a directional antenna in
> the presence of multipath.
>


That's absurd. I routinely watch 8-VSB with adjacent channel analog
stations totally unwatchable due to multipath. In one case at
various times the analog will not even sync in.

This is with a third generation receiver.

Doug McDonald
Anonymous
March 8, 2005 2:13:16 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

In article <112phngkeroc137@corp.supernews.com>,
"Matthew L. Martin" <nothere@notnow.never> writes:
> Frank wrote:
>> "Doug McDonald" <mcdonald@SnPoAM_scs.uiuc.edu> wrote in message
>> news:D 0g29n$j6p$1@news.ks.uiuc.edu...
>>
>>
>>>14 km is only 8.5 miles. That's exceedingly unimpressive. When
>>>one of our stations (a channel 41) was at low power (1.5 kW ERP ....
>>>not transmitter power) and at 180 feet up their tower I received it
>>>with no problem with a simple twin-bowtie indoor antenna. This
>>>is 26 kM from the transmitter. Oh yes ... that's with the
>>>antenna pointing the wrong way.
>>>
>>>This, of course, is 8-VSB.
>>
>>
>> The station actually has a range of about 60km though reception with an
>> indoor antenna will vary as Sydney can be a difficult city for
>> transmission.Well, I was impressed with it because a 140kw ERP analog UHF
>> station that use to transmit from the from the same site provided an
>> absolutely unwatchable picture here.
>>
>
> This is very common here in the US. 8-VSB often times yields a perfect
> picture where NTSC will produce something unwatchable. This situation
> will get even better as more and more DTV stations go to higher power.
>
Another thing that will make the already very good 8VSB work better than
it already does is the loss of the high peak power analog transmissions...
Imagine that the antenna farms that have co-located 8VSB and NTSC, no longer
having the NTSC (jammer) broadcasts!!! The biggest problem that I have
seen is more related to overload and near-channel interference than 'multipath'
per se. This could even be part of the very RF noise intense NYC environment.

John
Anonymous
March 8, 2005 2:13:17 AM

Archived from groups: alt.tv.tech.hdtv,sci.engr.television.advanced,sci.engr.television.broadcast (More info?)

John S. Dyson wrote:
>
>
> Another thing that will make the already very good 8VSB work better than
> it already does is the loss of the high peak power analog transmissions...
> Imagine that the antenna farms that have co-located 8VSB and NTSC, no longer
> having the NTSC (jammer) broadcasts!!!

We have a case where there is an adjacent channel ATSC-ATSC problem:

There is one ATSC on channel 41 16 miles distant, and
another one on channel 42 but 68 miles diatant. If you
point a high gain channel 41-44 antenna at 42 you get a channel 44
which is one mile closer than the 42 quite reliably (and they
are about the same power and tower hright) but 42 is gettable
only in good tropo conditions. Luckily, 41 and 42 are co-owned
NBCs.

Doug McDonald
!