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"trellis-coded modulation." I read that it's used in all high order modulation schemes, I.E: 8/16/32PSK and 16QAM.
According to what I've read, DVB-S = QPSK and all higher orders of modulation, I.E: DVB-S2 = 8PSK, 16PSK, 32PSK and others. Which modulation scheme is used, is left to the uplinker. My thinking is that the cost of 16 or 32PSK (hardware)outweigh the benefits, or another way to say: 8PSK is the most cost effective.
CBC on F1- Well, maybe, Videoguard, I believe, doesn't follow the UTI DVB standard. I believe it's an "in-house" digital standard. Much like DCII. (Only used in NA for a specific service. I.E:whoever they could sell it to) So then yes, it's digital, and may use the 8PSK modulation scheme, but the stream encoded is non-standard. So, in my view, calling it DVB-S 8PSK doesn't fly. Should be called Videoguard or Videoguard8. The 8 signifying that it's using 8PSK modulation.
My actual original question could read as follows.
Does the QPSK-8PSK setting do anything, in The Pansat 9200? Because in 2+yrs of use, I don't think it has, or does anything. It doesn't miss any 8PSK, if left set on QPSK. The only setting that matters is the DVB-S/S2 setting set to DVB-S2, to scan in the 8PSK transponders.The only thing I see the 8PSK setting do is put 8PSK in the channel info bar on bottom of screen.
Is that all it's for? Or am I missing some other feature or transponders. And If I am missing some feature or transponder, let me know of their location and a little info as to how to program them in the 9200. I'd be greatful. Thanks.

Videoguard is NDS's conditional access system. It is not modulation based. CBC uses it and so does Directv.
VideoGuard Conditional Access and Digital Rights Management Solutions by NDS

FaT Air said:

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Does the QPSK-8PSK setting do anything, in The Pansat 9200? Because in 2+yrs of use, I don't think it has, or does anything. It doesn't miss any 8PSK, if left set on QPSK. The only setting that matters is the DVB-S/S2 setting set to DVB-S2, to scan in the 8PSK transponders.The only thing I see the 8PSK setting do is put 8PSK in the channel info bar on bottom of screen.
Is that all it's for? Or am I missing some other feature or transponders. And If I am missing some feature or transponder, let me know of their location and a little info as to how to program them in the 9200. I'd be greatful. Thanks.

Click to expand...

Assuming that you're now talking DVB-S2 QPSK or 8PSK, then I think I'd say that it SHOULD make a difference, and in some receivers it DOES make a difference. However some receivers have tuners that just don't seem to care what parameters you have set. My TT3200 will lock regardless of what FEC you set, and doesn't have a setting for QPSK or 8PSK. On the other hand, my other S2 receivers, (ie Diamond 9000, Coolsat 8100, Azbox Elite) need to be set on the proper parameters (it's been a while since I've used the Coolsat, so I'm not as positive about it, but I think so). The one exception is the Azbox has a tendency to sometimes lock on an illegal 7/8 FEC in both QPSK AND 8PSK mode. Otherwise though, if the transponder is QPSK, you must set it on QPSK, and if the transponder is 8PSK, you must set it on 8PSK.
There ARE some transponders that are in a dual mode, where they can be locked with either QPSK or 8PSK, but those are rare.
So anyway, I'm not familiar with the 9200, but from what you describe, it sounds similar to my TT3200, whereby it must use a tuner that must do DVB-S2 in some sort of automatic mode, where the settings don't matter.
BTW, with my TT3200, since it doesn't even have a QPSK/8PSK setting, it's difficult for me to report transponders I find with it, because I can't tell what the parameters are. I can sometimes tell by looking at the mux bitrate in TSREADER, which usually makes it pretty obvious whether it's QPSK or 8PSK, but often the bitrates aren't exact enough to determine the FEC. So if I find a feed and go to report it somewhere, I usually have to plug it into one of my other receivers to verify the parameters.

Back to the DVB 8PSK vs Trellis thing, it was always my impression (just from reading various forums) that the DVB spec didn't have 8PSK defined, and that perhaps Trellis is what it would have been if it was defined, but is really more of a proprietary spec, similar to the Turbo 8PSK. And I really get the impression that there are a LOT of these proprietary specs, or perhaps uplinkers who have set the parameters of there equipment in ways that don't comply with the normal DVB or DVB-S2 specs. There are many many transponders up there that are nice strong transponders that I can't lock in any mode. Many are regular QPSK, apparently close enough to DVB that I get a "signal lock", but they don't give a "data lock" on any of the standard FEC values. When I try to lock with my Broadlogic, I get a quick signal lock, and then I see it trying all the FEC values, one by one, over and over, and it doesn't find one that matches. So I'm guessing that these signals just aren't following the standard. Perhaps they have some non-standard value for the data size that's normally 188, or something like that. But I see all sorts of signals up there that for one reason or other can't be locked with any mode I can do, and I don't think they are all Trellis, as many are QPSK, so there must be ways to set the commercial equipment so that regular tuners won't lock them.

Is there any solution to demodulate 8psk on skystar 2? (not skystar 2 HD) I mean a software able to decode 8psk without hardware upgrade to skystar 2 HD
Thanks

All modulations are decoded in hardware. No way todo software decode with that hardware

UDL