goaliebob99 said:
The broadcom chip set supports 16QAM but I am surprised they could even attempt to get the FEC so low at 7/8... Thought it was 3/4 max... This is in excess of 69 Mbit/sec...
Uplink Activity For WeD. May 10th 2006
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The broadcom chip set supports 16QAM but I am surprised they could even attempt to get the FEC so low at 7/8... Thought it was 3/4 max... This is in excess of 69 Mbit/sec...
if you look at the chart, dish is running between 27, 30 Mhz bandwith I belive.. (looking at the fec rate) and if they run this on all there Tp's and Hd channels that would double the space 
add MPG 4 to the mix and dish could do some major damage and major uplinking while keeping everyting looking good with full rez... Please dish if you can hear me ( im on my hands and knees) Give me fullrez hd on all channels with this at a good bitrate and keep it that way.. you will get SOOO many D* subs heading your way!!! And POSITIVE Press overage from stophdlite.com
add MPG 4 to the mix and dish could do some major damage and major uplinking while keeping everyting looking good with full rez... Please dish if you can hear me ( im on my hands and knees) Give me fullrez hd on all channels with this at a good bitrate and keep it that way.. you will get SOOO many D* subs heading your way!!! And POSITIVE Press overage from stophdlite.com
goaliebob99 said:Not according to the ATSC... here is what im soo excited about.. I actually would like to see dish move all there hd channels like this if it works good enough..
Well thinking back, I think it was the 6000/811 chip broadcom chipset that was limited to 3/4 FEC with a 16QAM signal. I do not know which chip (and its limits) for the 411/211/622. They (Dish) have always been so conservative in the past with only 2/3 FEC on 8PSK... They are really testing it now with 7/8 16QAM.
mike123abc said:
With dish moving to Mpg4 recivers I dont think this will be a problem any more after all this is a mpg4 channel that is avabile to subs...
Looking at that channel it looks good running that.. After all its the only one on the tp so it better look good LOL
JohnH said:
Explain more please
are you saying that the fec rate changes depending on whats up there or what modulation is used?The FEC Rate is variable depending on the content.goaliebob99 said:Explain more please
goalie, you should avoid those type of phrases as "Lots of test channels uplinked to 118.7 Location from all Regional and main uplink centers"
Nothing is _uplinked_ to moving AMC-16; it's just SI tables populated.
BTW, could you make please again those couple bins with PID 0x0010 and 0x0011 ?
Interesting to see that 'QAM' flags.
Nothing is _uplinked_ to moving AMC-16; it's just SI tables populated.
BTW, could you make please again those couple bins with PID 0x0010 and 0x0011 ?
Interesting to see that 'QAM' flags.
my old dinosaur 4900 even has a 118 location in it's check signal screen.. This must be a recent change because prior they had a 119k location. (or was it 118k) I cant remeber.. now it just says "118"
--Matt
--Matt
I don't wanna be the bearer of bad news, but they aren't running 16QAM. If you look at the TSReader output again:
TSReader groups 16QAM (DVB-DNG) and QPSK (Turbo) together in its output, the actual modulation could be either 16QAM or QPSK Turbo. QPSK turbo coded with a 7/8 FEC rate has been tested before by dish. I've seen that before when they were testing QPSK turbo on 129 last year. So my gut feeling is this is not 16QAM but rather QPSK turbo. I'm not 100% sure on this as I'm at work and can't check it out, but I'll ask around and post again tonight.
As for the chipset Dish uses, the Broadcom 4500 is the same IC that has been used since the 6000 8PSK addon module. Every HD box since then has it built in, and even some of the newer SD boxes have this demodulator.
As a side note, dish was testing turbo 8PSK with 5/6 FEC on 129 a week or so ago, giving about 50mbit per transponder.
Edit:
Max bandwidth with 21500 QPSK 7/8 FEC is just under 38Mbit/s.
TSReader groups 16QAM (DVB-DNG) and QPSK (Turbo) together in its output, the actual modulation could be either 16QAM or QPSK Turbo. QPSK turbo coded with a 7/8 FEC rate has been tested before by dish. I've seen that before when they were testing QPSK turbo on 129 last year. So my gut feeling is this is not 16QAM but rather QPSK turbo. I'm not 100% sure on this as I'm at work and can't check it out, but I'll ask around and post again tonight.
As for the chipset Dish uses, the Broadcom 4500 is the same IC that has been used since the 6000 8PSK addon module. Every HD box since then has it built in, and even some of the newer SD boxes have this demodulator.
As a side note, dish was testing turbo 8PSK with 5/6 FEC on 129 a week or so ago, giving about 50mbit per transponder.
Edit:
Max bandwidth with 21500 QPSK 7/8 FEC is just under 38Mbit/s.
Last edited:
Ok this makes much more sense. The BCM4500 (http://www.broadcom.com/collateral/pb/4500-PB06-R.pdf) only support 16QAM at 3/4 FEC. 16QAM takes a LOT more TP power than 8PSK. I was very suprised that E* would even be testing it.
8PSK 5/6 FEC turbo would be about the limit of the current TP power to have a decent chance of avoiding rain fade. 129 would have to run a TP at double power for it to work.
Only place I see TP power for 16QAM would be in the center of a full power spot beam, even then rain fade would be a large problem.
8PSK 5/6 FEC turbo would be about the limit of the current TP power to have a decent chance of avoiding rain fade. 129 would have to run a TP at double power for it to work.
Only place I see TP power for 16QAM would be in the center of a full power spot beam, even then rain fade would be a large problem.
Good catch on the 3/4 FEC for 16QAM mode.
I noticed many more errors on the transport stream when they were running 8psk 5/6. Not sure if they were visible in the video/audio, but they were detected by TSReader when I was tuned to it. Of course it was cloudy and drizzly that day, which means my signal level from 129 isn't all that great.
I agree that if they were ever to use that modulation for subscribable content, it would be used on the higher powered spots, possibly for hd lil.
I noticed many more errors on the transport stream when they were running 8psk 5/6. Not sure if they were visible in the video/audio, but they were detected by TSReader when I was tuned to it. Of course it was cloudy and drizzly that day, which means my signal level from 129 isn't all that great.
I agree that if they were ever to use that modulation for subscribable content, it would be used on the higher powered spots, possibly for hd lil.
Shows the total mux bitrate in the lower middle and the parameters of that TP on the lower left panel. 129W 12296MHz
Nice to see espn2hd with a healthy 17Mbit/s!
