227 replies to this topic

[digitalj]

alanh, on 27 April 2012 - 12:59 PM, said:

Funny about MVC MPEG-4 compressors, they produce a 2-D signal and also compress a depth signal.


AlanH

How many more times are you going to make this false claim?

MVC does not in any way shape or form use a depth signal, it's just like joint stereo audio, 2 simultaneous images are encoded together, if there is anything identical between the 2 images, then rather than encode it twice, it is encoded once and a signal tells the decoder to copy from view 1 to complete view 2. MVC is not even limited to just 2 views either, it can be many, say a network wanted to have multiple angles of footage available to viewers, they can either have separate encodings for each stream, or they can encode them all together as MVC which will be more efficient than having separate encodings.

[davmel]

alanh, on 28 April 2012 - 12:11 AM, said:

So TXA does not own any UHF transmitters on any of their Main transmitter sites.

Funny then how it was TXA that provided the UHF transmitter for the Brisbane 3D trial two years ago:
http://www.broadcast...ssion-is-on-air

[alanh]

davmel,
Was it a BA transmitter on a TXA site. This is a backup arrangement used in all capital city as stated by TXA. TXA has no need for any expensive high powered UHF transmitters on capital city sites because all of their company is owned by the three capital city networks none of which transmit high powered UHF.

"TX Australia’s Mt Coot-tha site". BA did not say it was a TXA transmitter.

AlanH

[nbound]

alanh, on 28 April 2012 - 12:42 PM, said:

davmel,
Was it a BA transmitter on a TXA site. This is a backup arrangement used in all capital city as stated by TXA. TXA has no need for any expensive high powered UHF transmitters on capital city sites because all of their company is owned by the three capital city networks none of which transmit high powered UHF.

"TX Australia’s Mt Coot-tha site". BA did not say it was a TXA transmitter.

AlanH

TX Australia said:

3D Free to Air Transmission in Australia
First in the World

19 May 2010: Transmission service providers TX Australia Pty Limited (TXA) and Broadcast Australia (BA) launched "free to air" DTV 3D transmission from 00:00hrs today in Brisbane on UHF Channel 50 from TXA's Mt Coot-tha site and in Sydney on UHF Channel 35 from BA's Gore Hill site in a world first terrestrial broadcast over the air, on DTV logical channel number 40.
Nine Network Australia and SBS have been given scientific test transmission licences from the 19 May 2010 until the 19 July 2010 to enable consumers, retailers and manufacturers to experience live sporting events and other material.
The trial broadcast will demonstrate the potential of 3D television and the enhancements enabled by digital technology. The NRL State of Origin series and a number of FIFA World Cup games from South Africa will be shown in 3D during this period.
The trial 3D transmission is progressively been rolled out on UHF Channels in Melbourne (Ch35), Adelaide (Ch29), Perth (Ch35), Newcastle (Ch35) and Wollongong (Ch50) and all will be on DTV logical channel number 40.
Transmission service providers TXA and BA are working collaboratively in bringing this trial transmission of Nine and SBS 3D services and would like to thank industry partners BroadcastONE (Harris agent) and Radio Frequency Systems (RFS) who have contributed loan equipment to this historic broadcast transmission event.

http://www.txaustralia.com.au/news.asp


It would appear they were likely loan transmitters.

Edited by nbound, 28 April 2012 - 01:01 PM.

[CWulf]

Hi

There are reports on the last lot of trials on the ACMA website at http://www.acma.gov....01/pc=PC_312131 which provide fairly good details on what transmission arrangements were used.

I could pull out the appropriate bits and restate here but it's more entertaining to wait and see if Alan has any comments on where the reports got it wrong   Interestingly there are comments on why lower power transmitters were able to achieve equivalent coverage to the SBS using 16QAM.  This is obviously wrong given Alan's previous statements re CTV coverage using QPSK and lower power transmissions (or did I miss the email where Alan admitted he was wrong - apparantly he does admit when he is wrong but I'm yet to find one of those posts )

[digital doctor spock]

It is logical that knowing that SBS transmitters were NOT used and that as stated previously quoting TX Australia that loan UHF transmitters (Harris) and loan combiner modules (RFS) were used. And on another subject QPSK has a 10 dB advantage over 64QAM ( I am not sure of what the dB advantage is over 16 QAM) thus only requiring transmitter power 10dB less than SBS such as the digital community TV service in most capital cities. I am not sure that it is logical to assume that TX Australia does not own any UHF transmitters. And in regards to the 2010 3D trial I understood that it was a service provided by channel 9 where it was their program input infrastructure at a TX Australia site that provided coverage for Ch 9 3D trial AND the SBS 3D trial. According to my sources the 2010 3D trial has nothing to do whatsoever with Broadcast Australia or the SBS transmitters (which are owned by Broadcast Australia). Additionally the license holder of the 2010 3D trial was solely held by Channel 9 and their transmission provider is TX Australia. And it was Chanel 9 and TX Australia who provided the 2010 3D trial for Ch9 rugby and SBS world cup. It is not without precedent where a Channel 9 affiliate have broadcast SBS programs (Soccer) through the Channel 9 affiliate transmitter. There is a long standing relationship between Channel Nine and the SBS.

[alanh]

Reports on the last trial to the ACMA
http://www.acma.gov....ort_to_acma.pdf
http://www.acma.gov....ort_to_acma.pdf.
Note the SBS comment of poor coverage in Brisbane because the TXA antenna is not designed for channel 50.

Normal arrangements for 2-D main transmitters
Red is the backup
Adelaide:
SBS33 ntl Tower Summit Road CRAFERS TXA Crafers Site Tower 115 Mount Lofty Summit Road CRAFERS
Brisbane:
SBS 36
Channel 2 Site MOUNT COOT-THA TXA Q-Site Tower 632 Sir Samuel Griffith Drive MOUNT COOT-THA Channel 2 Site MOUNT COOT-THA
The channel 2 Site is owned by BA
Melbourne:
SBS 29
TXA Ornata Road Site Tower 12 Ornata Road MT DANDENONG NTL (ABV-2) Tower Eyre Road MT DANDENONG NTL (ABV-2) Tower Eyre Road MT DANDENONG
NTL was taken over by BA.

Perth
NEW Tower TX Australia Site 255 Welshpool Road East 3km WNW of CARMEL ABC / SBS TV Tower Broadcast Australia Site Television Road 600m SW of BICKLEY ABC / SBS TV Tower Broadcast Australia Site Television Road 600m SW of BICKLEY
NEW tower is owned by TXA and normally transmits NEW11 digital programs and as a backup can transmit TVW, STW (owned by WIN), ABC and SBS
ABC/SBS tower is owned by BA.

Sydney:
ATN 6 TXA Artarmon Stie Tower 192 - 196 Hampden Rd Artarmon
ATN 6 TXA Willoughby Site Tower 15 Richmond Av Willoughby
TCN 8 TXA Willoughby Site Tower 15 Richmond Av Willoughby
TCN 8 TXA Artarmon Site Tower 192 - 196 Hampden Rd Artarmon
TEN 11 TXA Artarmon Site Tower 192 - 196 Hampden Rd Artarmon
TEN 11 TXA Willoughby Site Tower 15 Richmond Av Willoughby
ABN 12 ABN Tower 221 Pacific Highway Gore Hill
ABN 12  TXA Artarmon Site Tower 192 - 196 Hampden Rd Artarmon
TSN 29 ABN Tower 221 Pacific Highway Gore Hill
SBS 34 ABN Tower 221 Pacific Highway Gore Hill
SBS 34 ABN Tower 221 Pacific Highway Gore Hill
SBS 34 TXA Artarmon Stie Tower 192 - 196 Hampden Rd Artarmon

The above list is for licences. The TXA sites only need one additional band 3 digital transmitter to provide a backup for any transmitter failure. Within band 3 the transmitter can be easily retuned.
As the TXA site says they provide access to national broadcasters. The national broadcasters (ABC & SBS) use Broadcast Australia as their transmitter contractor.
Obviously BA installed a Band 4 antenna for its transmitter.

AlanH

[James T Kirk]

alanh, on 28 April 2012 - 09:16 PM, said:

Reports on the last trial to the ACMA
http://www.acma.gov....ort_to_acma.pdf
http://www.acma.gov....ort_to_acma.pdf.
Note the SBS comment of poor coverage in Brisbane because the TXA antenna is not designed for channel 50.

AlanH

AlanH

Would you like to re-read the reports and correct your Brisbane channel 50 poor coverage comment?

[MLXXX]

I will assist alanh.

Alanh claimed:

alanh, on 28 April 2012 - 09:16 PM, said:

Reports on the last trial to the ACMA
http://www.acma.gov....ort_to_acma.pdf
http://www.acma.gov....ort_to_acma.pdf.
Note the SBS comment of poor coverage in Brisbane because the TXA antenna is not designed for channel 50.

The second pdf states:

The coverage of the 3DTV trial was equivalent to the existing coverage of the SBS service except in Brisbane. The Brisbane transmitter was operating on a lower power than the existing service and some viewers in Brisbane did not have the appropriate antenna that covers channel 50. As a result, some Brisbane viewers were disappointed at not being able to receive the 3D transmission.

The second pdf supports James T Kirk's earlier comment regarding some viewers lacking a suitable antenna for channel 50.

The first pdf contains a positive, almost glowing, assessment of the coverage in Brisbane.

Edited by MLXXX, 28 April 2012 - 11:35 PM.

[alanh]

MLXXX,
I have never disputed that band 4 antennas do not receive channel 50 very well. In fact it should be that way. I was commenting on channel amplifiers in MATV systems.

As for the transmitted signal it had a lower effective radiating power than SBS which adds to the problem.

AlanH

Edited by alanh, 29 April 2012 - 01:17 AM.

[MLXXX]

AlanH, at much lower power, but (as mentioned in the first pdf) using a much more robust modulation (16-QAM).  No mention could I see in the pdf, of your point: "because the TXA antenna is not designed for channel 50".


According to the first pdf, very low powered transmitters were used, first a 200W unit (delivering 5kW ERP from the SBS omnidirectional antenna), and then a 1kW transmitter.  The "upgraded transmitter" was reported to provide sustained reception up to Caloundra to the North, and stopping just short of Southport to the South. (These locations are well outside Brisbane.)

It was also reported that in some areas there was better reception than of SBS digital TV using 200kW ERP!  Such was the advantage of using average 16-QAM modulation parameters compared with average 64-QAM parameters.

As there was only one video stream to broadcast, 16-QAM supported a sufficient bitrate. The video stream was approximately 14Mbps. For the efficient MPEG-4 AVC codec, that provided a very high standard of broadcast picture quality.  It was arguably the best video quality ever broadcast in Australia, albeit in a side by side 3D format.

Edited by MLXXX, 29 April 2012 - 08:26 PM.

[DrP]

The UK's prior exclusive use of 16 QAM demonstrated its robustness and coverage at low transmission levels.  It really is quite silly to argue against demonstrated reality.

Edited by DrP, 29 April 2012 - 05:54 AM.

[James T Kirk]

James T Kirk, on 28 April 2012 - 10:17 PM, said:

AlanH

Would you like to re-read the reports and correct your Brisbane channel 50 poor coverage comment?

Apparently not!
More evidence AlanH is to be treated with contempt, in this case he was unable to distinguish between transmit and receive antenna systems in quite a simple and straight forward report.

[davmel]

The channel 9 Olympics 3D satellite feed is now up and running on Optus D1 (12650 MHz @ 10500 kS/s) and unencrypted FTA so it all looks good to go as promised once the capital city translation sites go active.
I don't know why they didn't go with Optus C1 again this time as more people could easily access it without rotating their dish, but hey it's still available FTA to anyone anywhere in Australia that is determined to use their 3D TV to watch the Olympics.

[Slattery]

I gather you need your own dish to point to Optus D1 at the moment to view the 3D satellite channel?
Has there been any word yet on when FTA transmissions will begin to home TV's?
At least by showing it on Channel 9 we will be able to archive it on our PC's for future viewing in its native format, unlike Foxtel.

[nbound]

You can always get a DVB-S card for your PC. All kinds of interesting stuff occasionally to be recorded.

[davmel]

Slattery, on 03 June 2012 - 10:15 PM, said:

I gather you need your own dish to point to Optus D1 at the moment to view the 3D satellite channel?

Yes, you can re-point a dish previously used for Foxtel/Austar if you're no longer using it for those services or watching Al Jazeera.

Quote

Has there been any word yet on when FTA transmissions will begin to home TV's?

There is little point wasting power transmitting anything until the overseas 3D feeds are available. They need to be allocated a license for the broadcast that will probably only be given for a month so with the duration of the Olympics I wouldn't expect the terrestrial re-transmissions to start until say 2 weeks before the Olympics (so viewers have enough time to tune into the channel in advance). Therefore I'd expect transmissions to start in week 1 or 2 of July.

Quote

At least by showing it on Channel 9 we will be able to archive it on our PC's for future viewing in its native format, unlike Foxtel.

Indeed. I've seen nothing mentioned by Foxtel if they will even bother re-transmitting the Olympics 3D BBC channel on their own 3D channel. Even if they did it would be a poor inferior low bitrate version of the same feed available through the Nine network special 3D broadcast transmission. Foxtel's re-transmission of the 2010 3D trials was noticeably inferior and that was way back when they had half decent HD/3D bitrates!

[Craig]

Nine Network 3D info:

http://nine.com.au/Olympics3D

[GoForMoe]

Craig, on 08 June 2012 - 04:30 PM, said:

Nine Network 3D info:

http://nine.com.au/Olympics3D

LCN 95 is an interesting choice - which further doesn't help explain to the public that this is a temporary trial and there is no guarantee of future 3D services. No doubt between the 16th and the 29th plenty of 3DTVs will be happily sold on the promise of 3D broadcasts being on air and then the complaints starting to roll in on the 14th of August when it all disappears again. These forums still have comments popping up occasionally with complaints about the last 3D trial being a con on consumers - and despite their statements, Nine look no closer to actually making it obvious to the public how small the chances of long term 3D on FTA are.

The linked PDF contains TX Australia coverage projections - including the very good coverage projections for the 80kW service in Sydney. Indeed I think all the services are on higher power levels than the last trial, though not sure.

[davmel]

GoForMoe, on 08 June 2012 - 05:02 PM, said:

The linked PDF contains TX Australia coverage projections - including the very good coverage projections for the 80kW service in Sydney. Indeed I think all the services are on higher power levels than the last trial, though not sure.

Yeah, it's interesting how the Melbourne CBD and St. Kilda road area is in an RF hole. Virtually the entire Melbourne suburban basin is covered except for the city itself! ROFL. I guess people in the city can always put up a sat dish on their apartment balconies....

[Craig]

It's pretty clear that this is a 3D TRIAL.  No permanent 3D channel is promised or guaranteed.  With all Foxtel's HD channels, how many are 3D?  None, nana, nil.  Credit to Nine where it's due.

[peterca]

Craig, on 08 June 2012 - 07:44 PM, said:

With all Foxtel's HD channels, how many are 3D?  None, nana, nil.  Credit to Nine where it's due.

Foxtel has one 3D HD channel, channel 201.

[davmel]

peterca, on 08 June 2012 - 08:46 PM, said:

Foxtel has one 3D HD channel, channel 201.

It's safe to assume that Craig was reffering to the Foxtel HD Olympics channels. It is pretty ridiculous that Foxtel has allocated 8 HD channels and none of them are for 3D content.

[miata]

davmel, on 08 June 2012 - 08:50 PM, said:

It's safe to assume that Craig was reffering to the Foxtel HD Olympics channels. It is pretty ridiculous that Foxtel has allocated 8 HD channels and none of them are for 3D content.

Beacause 9 is doing the 3D portion of the coverage and Fox aren't re-broadcasting that, it will be avaliable only on 9 and only in certain areas.

[davmel]

miata, on 08 June 2012 - 09:08 PM, said:

Beacause 9 is doing the 3D portion of the coverage and Fox aren't re-broadcasting that, it will be avaliable only on 9 and only in certain areas.

Nine and Foxtel have jointly bid for the Olympics and have access to exactly the same source from the OBC including 3D coverage. But only Nine has bothered to show the 3D content for some strange reason.
Foxtel have no reason to re-broadcast the Nine 3D coverage (which is just a re-broadcast of the BBC 3D coverage) as Foxtel could make their own 3D coverage from the source feed at the OBC.