8PSK Module
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the Uruguayan mux on Hispasat is DVB-S2 (8PSK) and MPEG4 and it is all SD. As per lyngsat there are 3 TP on 110 W that are 8PSK but some use MPEG 4 and some MPEG 2.
As per this link : Improved digital video broadcasting
The RF layer of the DVB-S2 signal is divided into physical layer frames that do not need to use the same coding and modulation.
Not only that, the same transponder could have SD TV using DVB-S and HD signals using DVB-S2.
You have to see each transponder on a satellite as an allocated bandwith (whatever the bandwith for that TP) on a transmission line (in this case the whole SAT is the tranmission line) that in this case receives a signal, cleans and amplifies it and then retransmit it at a lower frecuency. But as far as the TP is concern like in a transmission line it does not care about the modulation scheme or wether is digital or analog or anything else, just the band of frecuencies.
Therefore in principle, a transponder is a transparent repeater, capable of supporting any modulation and you could mix them but it could happen that intermodulation or noise or who knows what else start affecting the performance of the TP after you start adding or activating different carriers. It is simpler to operate and set up and troubleshoot a TP that uses the same type of signals rather that one that mixes several different ones pretty much like me having analog cable, digital QAM cable, XM radio that uses COFDM I beleive and QPSK SAT signals all running along the same coaxial cable, the whole bandwith from 54 Mhz to 2.5 GHz could be seen as my own TP in my house. the principle is the same.
As per this link : Improved digital video broadcasting
The RF layer of the DVB-S2 signal is divided into physical layer frames that do not need to use the same coding and modulation.
Not only that, the same transponder could have SD TV using DVB-S and HD signals using DVB-S2.
You have to see each transponder on a satellite as an allocated bandwith (whatever the bandwith for that TP) on a transmission line (in this case the whole SAT is the tranmission line) that in this case receives a signal, cleans and amplifies it and then retransmit it at a lower frecuency. But as far as the TP is concern like in a transmission line it does not care about the modulation scheme or wether is digital or analog or anything else, just the band of frecuencies.
Therefore in principle, a transponder is a transparent repeater, capable of supporting any modulation and you could mix them but it could happen that intermodulation or noise or who knows what else start affecting the performance of the TP after you start adding or activating different carriers. It is simpler to operate and set up and troubleshoot a TP that uses the same type of signals rather that one that mixes several different ones pretty much like me having analog cable, digital QAM cable, XM radio that uses COFDM I beleive and QPSK SAT signals all running along the same coaxial cable, the whole bandwith from 54 Mhz to 2.5 GHz could be seen as my own TP in my house. the principle is the same.
The azbox does not need an add in board for S2-qpsk or S2 8psk it tunes them in "out of the box"
"As per lyngsat there are 3 TP on 110 W that are 8PSK but some use MPEG 4 and some MPEG 2"
1st - Lyngsat is not accurate up to date; on the site you could find latest info (!)
2nd - all 8PSK transponders on 110W (include SB) are Turbo Coded.
For those who are looking for exotic: 129W, TID 4009/tp 9, 12340640 KHz, R, QPSK, 26000, 2/3 - KTVA_5604/KTUU_5608(H)/KAKM_5621, all MPEG-4. If someone from that DMA could check if it ITC, then ...
1st - Lyngsat is not accurate up to date; on the site you could find latest info (!)
2nd - all 8PSK transponders on 110W (include SB) are Turbo Coded.
For those who are looking for exotic: 129W, TID 4009/tp 9, 12340640 KHz, R, QPSK, 26000, 2/3 - KTVA_5604/KTUU_5608(H)/KAKM_5621, all MPEG-4. If someone from that DMA could check if it ITC, then ...
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HD Fan,
That is the quintessential definition of a "transponder" and all I ever knew them to be. Some comments elude to certain sats with tp's that were modulation specific, which made no sense to me. Even with the tech advances in the lifetime of digitaltv alone, I just couldnt see it, that's why I asked.
That is the quintessential definition of a "transponder" and all I ever knew them to be. Some comments elude to certain sats with tp's that were modulation specific, which made no sense to me. Even with the tech advances in the lifetime of digitaltv alone, I just couldnt see it, that's why I asked.
My statement was based on the fact that I have a sonicview hd8000 without an add-on board. When blind scanning a certain circular bird I found some unscrambled hd channels (mentioned in the wut section on march 29) and was able to watch them.
The original poster asked for an explanation in layman's terms and honestly I haven't understood half of what everyone has said here. I think what most people want to know is:
If I spend $100 for an add on board (or even an hd receiver) what channels or feeds will this allow me to legally watch that I couldn't without it?
That's what my reply was based on too, except that there are more than one DN sats doing the same thing. I generally use either my Twinhan card feeding a popcorn hour from Tsreader, or my diamond 9000 to view. So it's obviously not Turbo 8PSK. One day, I found the one whole satellite FTA, with premium HD channels and everything.
B.J.
Could you explain in details for unfamiliar, why and how using a Twinhan DVB-S (or S2 ?) card installed in one's PC with sat signal output controlled by TSReader program, and connected to that PC Popcorn Hour Media Player (via USB or network ?), it's easier to get QPSK modulated DVB-S MPEG2/4 HD channels on your HD Monitor than using only a PC with DVB-S Card?
Also, don't you think guys, a detail FAQ Thread in this forum's FAQ Section is a must have on this quite complex but important for most people topic? It should also have an updatable list of all HD channels, one can legally get in North America sorted by sat DVB standard, then modulation and encoding type.
Could you explain in details for unfamiliar, why and how using a Twinhan DVB-S (or S2 ?) card installed in one's PC with sat signal output controlled by TSReader program, and connected to that PC Popcorn Hour Media Player (via USB or network ?), it's easier to get QPSK modulated DVB-S MPEG2/4 HD channels on your HD Monitor than using only a PC with DVB-S Card?
Also, don't you think guys, a detail FAQ Thread in this forum's FAQ Section is a must have on this quite complex but important for most people topic? It should also have an updatable list of all HD channels, one can legally get in North America sorted by sat DVB standard, then modulation and encoding type.
Sounds like a challenge to me....lol. You are right, there is a lot of info that should be compiled to a single source, or at least the same thread, and there are a lot of guys here that have the experience with the available equipment that their contributions would be essential for a successful FAQ on the subject. Making reference to available equipment, and current publicly known and available channels, with details on mode, freq, etc, would remove the discussion from the abstract and give it some real world tangable references for us that are dumb as a box o' rocks on the subject. (I'm not implying you are in that box zamar, but if you think you should be, just tell me to move over and climb in....lol)
We have many member generated FAQs on the main FTA forum page. There was a running, 'live', open ended FTA FAQ that was around somewhere. I'm not sure what happened with that, but I agree, an HD vs DVB/DVB-S2 vs mpg2/mpg4 vs 4:2:2 vs 4:2:0 crossreferenced to real equipment and signals would be a fantastic source of reliable info on the subject. I have seen a number of good and detailed DVB tutorials, but none make reference to 'what we have to work with' so it is essential abstact learning. I'm sure it would be a formidable task. Nothing less that a group effort. The knowledge is here, I am certain of that.
Anyone feel they have the huevos to pick up the gauntlet???
The Twinhan {1020a} is a DVB-S card. Using TSREADER, I can stream either SD or HD, and either MPEG2 or MPEG4 over my 100mbps LAN. I can play the streamed video either on another computer {SD or slow HD MPEG2 only due to slow PCs) or to my ROKU HD1000 {SD or HD MPEG2}, or to my PopcornHour, which will take SD, HD MPEG2 and MPEG4. This is easier FOR ME, or actually a necessity for me, because to display HD on the computer, you need a pretty fast computer, and the computer I have my Twinhan card on is only 1.9 GHz, ie not fast enough for anything but low bitrate HD.
Short of looking at Lyngsat, which is typically innaccurate, I don't think you're going to see that, because when feeds like this are FTA most of these FTA forums don't allow posting such info in public places. I don't agree with the logic behind this BTW, but I abide by the rules of the various forums I read. Ie I thought it was a good idea when they recently tried to make the WUT thing public, and was dissappointed when the decision was reversed. I'm already in such groups in other forums, so I didn't want to join yet another secret group, but an open group would have sounded good.
Thanks, B.J.
Details and arguments are always appreciated. As to Standards FAQ, the topic is a must have, but can avoid direct disclosure of most sensitive things like the whole "new" Sat with clear DN HD feeds you mentioned. Its a complex area, most people are confused about, so they don't know what equipment to buy, what's the right upgrade pass and why. In other words - what I can get for the money? It would also help to explain, why there is such broadcast techniques diversity at the moment? Is it because many broadcasters can't upgrade their equipment fast enough? What advantages a given combo of a broadcast standard, modulation and compression can give to a particular broadcaster? Why some of them like DN offer a mix of various such combos? Why other broadcasters consider the same combo unsuitable pursuing a different one?
melgagra
Admittedly, I'm in the far end corner of that Dumb Box you mentioned, and desperately trying to get out of it. The best way to do it, in my view: discuss in such forums these complex issues with other guys who has a lot more equipment, experience and knowledge on the subject than me. There is a dilemma with this whole FTA thing. On one end, it was simplified to death with low cost Plug-n-Play equipment and "easy" slogan to deliver sales. On the other end, it still remains a complex electronics, communications, media broadcasting and space technology soup, some dumbs try to comprehend a bit broader and deeper.
Details and arguments are always appreciated. As to Standards FAQ, the topic is a must have, but can avoid direct disclosure of most sensitive things like the whole "new" Sat with clear DN HD feeds you mentioned. Its a complex area, most people are confused about, so they don't know what equipment to buy, what's the right upgrade pass and why. In other words - what I can get for the money? It would also help to explain, why there is such broadcast techniques diversity at the moment? Is it because many broadcasters can't upgrade their equipment fast enough? What advantages a given combo of a broadcast standard, modulation and compression can give to a particular broadcaster? Why some of them like DN offer a mix of various such combos? Why other broadcasters consider the same combo unsuitable pursuing a different one?
melgagra
Admittedly, I'm in the far end corner of that Dumb Box you mentioned, and desperately trying to get out of it. The best way to do it, in my view: discuss in such forums these complex issues with other guys who has a lot more equipment, experience and knowledge on the subject than me. There is a dilemma with this whole FTA thing. On one end, it was simplified to death with low cost Plug-n-Play equipment and "easy" slogan to deliver sales. On the other end, it still remains a complex electronics, communications, media broadcasting and space technology soup, some dumbs try to comprehend a bit broader and deeper.
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Could some of this information be added to "the list" much the same way that the nbc's are noted as 4:2:2? I notice on the list that a couple channels are marked s2. Is this all of them full time, itc that can be discussed in the open forum? Would it be possible to note which birds require universal or circular lnbs (by the satellite) on the list and which channels or birds require odd modulations like s2, 4:2:2 (by the channel) or turbo (by the satellite, ie: blind scan hd in turbo)?
I am very grateful for the hard work already done compiling the list and don't mean to belittle the list in any way.
I am very grateful for the hard work already done compiling the list and don't mean to belittle the list in any way.
hd fan
Citing from the BroadcastEngineering link in your above post that explains DVB-S2 standard options:
" Using 8PSK with the two symbols of each quadrant placed closer together than in the original 8PSK constellation diagram causes the DVB-S receivers to believe that they are receiving a QPSK signal while the DVB-S2 receivers detect all eight symbols."
Does it mean that when DN uses a DVB-S2 TP to transmit an HD MPEG2 channel under above conditions, older DVB-S HD Receivers recognize that signal as QPSK modulated and can decode it showing HD pic ? Is that why some people believe, DN transmits a lot of HD channels in QPSK, when in reality most of those may be actually transmitted in S2 8psk turbo?
As you said, most providers would still prefer separate TPs for DVB-S and S2, since mixing signals may add noise and require higher FEC, leading to bandwidth losses. It's important for broadcasters to continue support DVB-S receivers since most people still use them. As to considering any TP to be just a bandwidth delivery channel, which doesn't care what it transmits - is it correct? Would a DVB-S signal transmitting older TP need equipment upgrade to be able to re-transmit S2 signals? That means sending new sats to orbit.
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" Using 8PSK with the two symbols of each quadrant placed closer together than in the original 8PSK constellation diagram causes the DVB-S receivers to believe that they are receiving a QPSK signal while the DVB-S2 receivers detect all eight symbols."
It will lead to process meaningless data ( imagine missing part of 8PSK constellation), so no, nothing good will happen then. End of speculation. Period.
It will lead to process meaningless data ( imagine missing part of 8PSK constellation), so no, nothing good will happen then. End of speculation. Period.
fixed thread..the op was a hacker so after bannign him it deleted his posts (and threads)
sorry for the issue
sorry for the issue
and I thought I was the culprit lol. Last night after writing for almost , who knows how long , I tried to post my long reply and then bang , the whole thread had disapear and I could not find it anywhere!. I copied it before posting (it has happened to me before that after taking too much time writing I lost the connection somehow so now I tend to copy and paste before) to the wordpad so I will post it when ever I get home and have the time.
Smith P, not necessarilly , by using hierarchical modulation they could attain this, the european DVB-T (equivalent of the american ATSC) could use it to send 2 kind of services an HD version for most receivers and the SD version for mobile TV users or DVB-T receivers in very poor reception conditions. Their standard can use 3 modulations , QPSK, 16QAM and 64QAM as I recall. Of course it could not be a combination of QPSK and 8PSK but rather BPSK (only 2 symbols therefore 1 bit ) as the high priority service and 8PSK (8 symbols , 3 bits)as the low priority service for a total of 8 symbols, 3 bits that is 8PSK. The first bit would always be the BPSK service and will always be embeded at the begining of the 8PSK signal. So from every XYZ in the 8PSK constellation X belongs to the BPSK service , low quality , lower bitrate of course and XYZ are the 3 bits of the 8PSK higer bitrate lower priority service. In European OTA case they could use 64QAM that has 6 bits (2 power of 6 equals 64) as low priority HDTV service and QPSK with 2 bits SD version service for mobile TV for instance. It is always a compromise and it will be better to use only 1 kind but heck at least someone inside a mini van could watch their favorite major US network while they travel , actually major European network since the american ATSC standard does not have the capability to do this. sporry FCC, lol.
this is all theoretically and has been patented (google shows a Direct TV patent about this) and the 8PSK constellation has to be mapped hirearchically (becomes a non-uniform 8PSK constellation) accordingly and I beleive there is no equipment nor a TV provider implementing this , at least not yet. Maybe DVB-S2 will evolve in the future to implement this and finally be backwards compatible with QPSK receivers therefore legacy receivers will not have to be upgraded , for now that is not the case and not only Dish Network but also Bell TV here in Canada have upgraded their receivers accordingly.
DN will not do this anyways probably and even European TV stations might not implement it OTA either at least not in the near future (the narrower the gap between symbols the higher the errors on the low priority 8PSK service , HDTV probably) . Of course , technology will evolve as bandwith will always be scarce and more efficiency is needed.
In other words for now if Lyngsat shows a TP as QPSK MPEG 4 HD service it is QPSK and if it says 8PSK turbo FEC or turbo coded it is 8PSK turbo and as such you need a capable receiver. do not expect to watch an 8PSK TP with a HD QPSK receiver , not for now at least. That is why I insisted on getting the now not so new 9242 Bell receiver that is MPEG 4 and 8PSK compatible instead of the 9200 (only MPEG 2 although it was 8PSK compatible) that the Bell Store CSR wanted to sell me. Although , recently bell has upgraded for free the old 6100 receiver that is not 8PSK capable but who knows in the future , just in case , lol. Bell is supposed to start 8PSK service soon if it has not started yet , they have been testing for several months now. And guess what the result will always be .... the same crappy picture quality than before as they will add more HD channels on the already very narrow satellite bandwith.
Smith P, not necessarilly , by using hierarchical modulation they could attain this, the european DVB-T (equivalent of the american ATSC) could use it to send 2 kind of services an HD version for most receivers and the SD version for mobile TV users or DVB-T receivers in very poor reception conditions. Their standard can use 3 modulations , QPSK, 16QAM and 64QAM as I recall. Of course it could not be a combination of QPSK and 8PSK but rather BPSK (only 2 symbols therefore 1 bit ) as the high priority service and 8PSK (8 symbols , 3 bits)as the low priority service for a total of 8 symbols, 3 bits that is 8PSK. The first bit would always be the BPSK service and will always be embeded at the begining of the 8PSK signal. So from every XYZ in the 8PSK constellation X belongs to the BPSK service , low quality , lower bitrate of course and XYZ are the 3 bits of the 8PSK higer bitrate lower priority service. In European OTA case they could use 64QAM that has 6 bits (2 power of 6 equals 64) as low priority HDTV service and QPSK with 2 bits SD version service for mobile TV for instance. It is always a compromise and it will be better to use only 1 kind but heck at least someone inside a mini van could watch their favorite major US network while they travel , actually major European network since the american ATSC standard does not have the capability to do this. sporry FCC, lol.
this is all theoretically and has been patented (google shows a Direct TV patent about this) and the 8PSK constellation has to be mapped hirearchically (becomes a non-uniform 8PSK constellation) accordingly and I beleive there is no equipment nor a TV provider implementing this , at least not yet. Maybe DVB-S2 will evolve in the future to implement this and finally be backwards compatible with QPSK receivers therefore legacy receivers will not have to be upgraded , for now that is not the case and not only Dish Network but also Bell TV here in Canada have upgraded their receivers accordingly.
DN will not do this anyways probably and even European TV stations might not implement it OTA either at least not in the near future (the narrower the gap between symbols the higher the errors on the low priority 8PSK service , HDTV probably) . Of course , technology will evolve as bandwith will always be scarce and more efficiency is needed.
In other words for now if Lyngsat shows a TP as QPSK MPEG 4 HD service it is QPSK and if it says 8PSK turbo FEC or turbo coded it is 8PSK turbo and as such you need a capable receiver. do not expect to watch an 8PSK TP with a HD QPSK receiver , not for now at least. That is why I insisted on getting the now not so new 9242 Bell receiver that is MPEG 4 and 8PSK compatible instead of the 9200 (only MPEG 2 although it was 8PSK compatible) that the Bell Store CSR wanted to sell me. Although , recently bell has upgraded for free the old 6100 receiver that is not 8PSK capable but who knows in the future , just in case , lol. Bell is supposed to start 8PSK service soon if it has not started yet , they have been testing for several months now. And guess what the result will always be .... the same crappy picture quality than before as they will add more HD channels on the already very narrow satellite bandwith.
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HMMM........ Guess he blew it in another thread or via pm to someone. I didnt see anything in this thread to indicate his intentions. If anything it seemed he was looking for info on how to rx anything that wasnt illegal, at least in this thread.
Oh well, the thread still brought to light the need for a compilation of the aspects, limitations, and usages of the different modes, equipment, and signals that are publicly published.
Prime example of heed the warning or pay the price.the latter one
You do realize there is likely to be an increase in such things due to the number of soon to be 'starving' DVB box owners, right? That mod panel will prolly be getting a good workout in the near future....lol
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