Hey guys, fill the blanks! (channels per transponder)

simonhwsn

Well-Known SatelliteGuys Member
Original poster
Aug 4, 2009
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Mexico
One transponder is able to carry ____ channels with:

QPSK-MPEG2
QPSK-MPEG4-SD
QPSK-MPEG4-HD
8PSK-MPEG2
8PSK-MPEG4-SD
8PSK-MPEG4-HD

theorically, even if some of these combinations were never used.

thanks :D
 
I know Dish is just starting to implement it on Nimiq 5 but the number of SD channels on a 8PSK MPEG-4 TP should be greater than that for a QPSK MPEG-4 TP. It has been quoted elsewhere that there is a 25% bandwidth increase going from QPSK to 8PSK so if Dish has 23 SD channels on a QPSK MPEG-4 TP then Dish should be able to put 28 - 29 SD channels on a 8PSK MPEG-4 TP.
 
I agree. I was just going off thelist for what I see channel wise

Some of them are hard to figure out as Dish uses multiple channels but using the same bandwidth (HD channels in multiple number spots) so my numbers may not be 100% accurate ;)

But I know when Dish had 148 active they use to test how many channels they could put on a TP and just how "good" (using that term very loosely) they would look and MPEG4 QPSK they would do 20 at a time. 8PSK I can't check as a FTA box can't lock the Dish 8PSK (they use Turbo 8PSK)
 
Thanks

QPSK-MPEG2
12-13 SD channels...2-3 max HD

I though that MPEG2 encoding was used for SD only, "You lear something new every day" :D

8PSK-MPEG2
really no way to know as Dish doesnt use that

But it's technically possible, isn't it? here's one of the reasons why I'm asking, Dish Mexico (the Echostar-MVS joint venture, not the package) is using 311 and 322 receivers wich as far as i know are 8PSK compatible but MPEG2 only (hey, that would be a clue :D) so i was wondering if they will switch to 8PSK when Quetzsat 1 will be launched in 2011.
 
Sent my question to Digiblur and got this back...


That's a trick question...since you have to have the space on 110/119 to add it to 72.7.

But with that being said.... I posted a run down a while back but here's the raw numbers.

With them having only 16 transponders of the 32 they are currently running in 5/6 QPSK mode (30 megabit a TP) that's 480 megabits they currently have. They will transition to 8PSK 2/3 in a week or two. Those are typically around 40 megabits maybe a bit over. 40*16=640 megabits. 640-480=160 megabit gain. If they consolidate that's basically 4 free HD capable transponders. So if they run 7-8 HD's per TP that's about 30 HD channels.

But you have to remember what they add to EA has to be added to WA. They can't just add it to 129 either, since the folks that have 110/119/61.5 would be high and dry. They need to get something over to 61.5 to fire up the transponders that E3 and E12 can not physically use. I suspect they will add some HD local markets that are in bad need.
 
I though that MPEG2 encoding was used for SD only, "You lear something new every day" :D
nope. Bell ExpressVu (Canadian DTH provider) use to have their HD in MPEG2 QPSK. 2 channels per TP. Dish at one time did too (the old 110 HD package)

as for MPEG2 8PSK sure its possible. Dish just doesnt use it
 
Iceberg said:
as for MPEG2 8PSK sure its possible. Dish just doesnt use it
It's used for Alexandria, LA from 129°, 6 channels on the same beam as 4 HD channels. Also for Providence RI from 61.5°. Other recent additions Bend OR and Marquette MI are QPSK but Dish is requiring 8PSK receivers.
 

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