Exactly! I've tried telling him this but he seems fixated on Directv doing something more expensive and upgrading all the current international customers.
What is reverse band?
- Thread starter manowell
- Start date
- Latest activity Latest activity:
- Replies 57
- Views 13K
- Status
Exactly! I've tried telling him this but he seems fixated on Directv doing something more expensive and upgrading all the current international customers.
Well, if you decide to go to an all HD system, the gains from MPEG 2 go away pretty quickly. You go from a 5 Mbps - 7 Mbps Mpeg2 SD to a 2 Mbps - 5 Mbps Mpeg 4 SD. The gains at 101 really isnt going to be as much as you think it is. Also, if you decide to go to an all HD system, then the bandwidth available really reduces at 101, 99 / 103.
IF 110 / 119 go away at some point (If ATT decides to shut them down to save money) then you have to move all of that over to 101 99/103. So yes, I could see them doing something more expensive to save money.
Think of it this way.. If you shut down 110 / 119 and get rid of the lease at 95, you save tons of cash. You can sell the birds to someone who would want 110 / 119, and sell off the licenses, how much ATT would save by consolidating everything down to three core slots. The reverse band can be utilized for 4K and Internationals. Remember AT&T has lots of debt they have to pay down. You have to find places to cut costs to make money. This is one way of doing it should they go that route.
Except they aren't using anywhere near 5 - 7 Mbps for their MPEG2 - that's more the range they use for MPEG4 HD. As an example, 101 tpn 1 has 17 MPEG2 SD channels and 4 MPEG2 audio only channels, out of a total transponder bandwidth of about 34 Mbps, meaning slightly less than 2 Mbps per channel on average. MPEG4 is roughly 2x more efficient than MPEG2 so the MPEG4 SD channels would use 1 Mbps at equivalent quality, but let's be as pessimistic as possible and say Directv decides to greatly increase quality with their MPEG4 SD channels and uses the same 2 Mbps they use for MPEG2 SD on their MPEG4 SD channels. And let's say they want to move everything on 95 & 119 to 101. I'm guessing you think this is impossible. Let's see...
Directv currently has 250 HD channels, 11 MPEG4 SD channels, 414 MPEG2 SD channels, and 90 MPEG2 audio channels. There are a handful of HD only channels, I'm not sure how many, let's say there are 10 of them so 240 of the MPEG2 SD channels are duplicates of HD channels and simply go away. That saves us 480 Mbps.
So let's see what needs to move off 95 & 119. There are probably a few MPEG2 SD channels on 119 that are duplicates of HD channels that won't really move, but we'll be pessimistic again and assume there are actually zero such channels. Thus we need to move 61 MPEG2 SD channels off 95, and 74 MPEG2 SD & 16 MPEG2 audio off 119 - there are also three MPEG4 HD channels on 119, we'll move those to 99/103 where they really belong. To handle 135 MPEG4 SD channels moving from 95/119 to 101 we'd need 270 Mbps at our very pessimistic 2 Mbps figure, plus let's throw in another 10 Mbps for the 16 MPEG2 audio channels, for a total of 280 Mbps. That leaves us 200 Mbps from the 480 Mbps we saved by dropping all the MPEG2 SD duplicates, which equals roughly six transponders left over!
But wait, there's more! There are currently 6 transponders on 101 used for MPEG2 SD spot beams. Those will be discontinued and used for CONUS after MPEG2 goes away, which means we would have TWELVE unused transponders on 101, even moving everything off 95 & 119 to 101 using unrealistically pessimistic figures.
So yeah they will terminate the lease for 95, dump 110 & 119 (they have almost everything off 110, it will be shut down at any time now) and not need to move any non-4K channels to reverse band.
A whole lot here. Your numbers are a bit off. I was being a bit generous with MPEG 2 SD, but they do run between 1 and 5 Mbps and with statistical multiplexing, it's realistically more like between 1 Mbps & 3 Mbps depending on content and how many channels they pack a transponder with. This is what I have gathered from captures of the satellites stream I have taken. MPEG 4 SD runs as low as 500kbps and as high as 4 Mbps. MPEG 4 HD is between 2Mbps and 15Mbps but often runs around 6 - 8 Mbps give or take. It's not hard to figure out what the video is doing on the transponders taking captures. There is also null overhead that you did not factor in as well as transponder data on each transponder. We also would have the transponders at 101 that would be used due to PR moving from 110. Also, I'm not sure where you got that 101 tpn 1 has 17 channels, it's more like 14 and with MPEG 4 I could see 17 channels, but you missed out on my point that between MPEG 2 SD and MPEG 4 SD the difference would be between 500kbps and 1 meg at the most. That does add up, but you're also assuming that they would keep the same quality and lower the rates. If they kept the same rates and increased the quality by virtue of a better encoding method (Mp2 -> Mp4) then that negotiates any gains. It's all dependent upon how they want the customer experience to be.
IF 110 goes away. IF PR moves to 101. If 119, if that went away, you have SD Spanish and some local stations that would move. IF 95 goes the way you have international's that would move.
With the decrease in subs at some point, ATT is going to want to reduce costs. Migrating slots is the only way to do that effectively to keep your cost structure in line as that's a lot of cash spent maintaining spacecraft. With that said 101,103, and 99 will always be there as those are your three core slots anyone in the US can hit.
IT's my WAG that ATT would want to keep SD National on 101 and keep it strictly for that. You will have SD local's, SD national and SD for Purto Rico from 101 KU. 103 and 99 KA will continue to be for HD National, LIL, UHD, and SD Spanish. Keeping your core slots consistent between all services. 99 and 103 RB will be for future 4K, Internationals, and any other application that ATT can come up with, like using it the possibility for First Net, Time Warner HBO / Cinemax and TNT / CNN Distribution. Yes, I am sold on internationals going to RB. The amount of international customers ATT probably has, wouldn't make a difference at this point and I would be super surprised if they had over 500,000 international customers. While I don't know the number, I can't imagine that it's anywhere that would be that expensive to install a reverse band lnb as most if not all already have a slimline dish. Even if it cost the company 30 million to do it, spread that out over 3 years and it's 10 million per year. That's a tax write off for a company like ATT.
The thing is there is a whole slue of possibilities that can happen. Like why would ATT want to keep paying for an uplink in NYC for Time Warner when they have other facilities they can do it from with much cheaper taxes. When you think of it from a cost perspective of where they are saving money and where they have to spend money, it makes sense, and where placement goes on the birds as far as programming. It really changes your perspective. That's why I'm sold on it. Think where does ATT want to be 5 years - 10 years out. Again this is all speculation from a diffrent viewpoint.
Don't have time to read through and reply to everything yet but this has already been done. The reason they moved T15 to 101 was to use the PR beam so PR can receive 101 which they are. They no longer need 110, it will be shut down soon.
Here's the problem with your assumptions. It has been confirmed that Directv is dropping all SD duplicates, and will be moving some HD channels to 101. So all 240 odd MPEG2 SD duplicates, almost all of which are on 101, are going away. Regardless of how you want to play with the numbers, that frees up plenty of bandwidth to move the contents of 95 & 119 to 101 with plenty of bandwidth left over. Even before the 6 transponders currently doing spot beam duty on 101 for MPEG2 SD in certain large markets are converted to CONUS.
Now I'm not saying that everything on 95 & 119 will move to 101. Probably a lot of it will move to 99/103, but it will move to Ka, not reverse band. Because they have spare bandwidth now, and will have plenty more once they've shut down MPEG2 SD, and won't need to do something that will unnecessarily cost them a lot of money.
Maybe they are getting ready to move the 4K channels to reverse band? There was a while there where they had the reverse band SWM LNBs but the reverse band legacy LNBs took longer to arrive. Now that it has been around long enough, presumably any 4K customers who need it (big residential installs, sports bars using multiple HR54/C61K pairs for 4K TVs, MDUs, etc.) will be upgraded pretty soon.
I keep wondering if they will be using bonding at all in the next few years - until they have more 4K channels than they have reverse band transponders (36) it really isn't necessary.
I keep wondering if they will be using bonding at all in the next few years - until they have more 4K channels than they have reverse band transponders (36) it really isn't necessary.
Yeah ...
And there appear to be only one test channel on each RB tp.
So perhaps DIRECTV is both moving and planning a major expansion of 4K content to the RB?
Oh, and back in your post #14 slice you mentioned using the image frequency of the Ka band L.O. 18.05 GHz to downconvert the RB signals to between 350-750 MHz.
But the RB IFs are actually between 250-650 MHz (odd/even tps. from 99W) and 1650-2050 MHz (odd/even tps. from 103W). So don't see the 18.05 GHz L.O. of any use at all here.
But most likely a new DRO L.O. at 17.05 GHz, at least inside the RB legacy LNB to output IF signals on its coax ports 5 and 6.
Sent from my LG-H932 using Tapatalk
And there appear to be only one test channel on each RB tp.
So perhaps DIRECTV is both moving and planning a major expansion of 4K content to the RB?
Oh, and back in your post #14 slice you mentioned using the image frequency of the Ka band L.O. 18.05 GHz to downconvert the RB signals to between 350-750 MHz.
But the RB IFs are actually between 250-650 MHz (odd/even tps. from 99W) and 1650-2050 MHz (odd/even tps. from 103W). So don't see the 18.05 GHz L.O. of any use at all here.
But most likely a new DRO L.O. at 17.05 GHz, at least inside the RB legacy LNB to output IF signals on its coax ports 5 and 6.
Sent from my LG-H932 using Tapatalk
It would be nice if they threw up the NASA 4K channel, https://www.harmonicinc.com/media/2016/08/Harmonic_DS_NASA-TV-UHD.pdf.
I doubt they are planning a major expansion, there would be press releases from at least some of the channels that were going to be added.
You're right about the image frequency, I forgot about the 1650-2050 MHz band which they'd need an additional LO for. The reverse band LNBs must have four of them instead of only two, unless they've done something really weird. They have a patent for an LNB that uses a single LO frequency that gets multiplied, divided etc. to handle all the downconversion, though that seems more trouble than its worth.
It is still interesting about the reduced reverse band signal readings. I don't know why they would broadcast it with less power, unless it has to do with US / Canada coordination. I'd be curious to see what reverse band readings someone very close to the Canadian border gets, like Detroit or upstate NY. If they are still 80s then Canadian coordination is unlikely to be the reason, and it has to be inherent to the design of the LNB...which could really only be non-optimal geometry of the feedhorn.
This is correct that reverse band customers close to a DBS uplink site could receive interference in reverse band. The funny thing here is there is a reverse band LNB consumer dish installed at DBS uplink site within 30ft of an uplink antenna and pointed right over it. Apparently the particular reverse band LNB/dish I know of is not in service yet but it there will be a problem when it is.
That might be deliberate - they may want to see exactly how much interference there is. The uplink site may not need to use that dish (if they do they could simply shield it or locate it on the other side of a building) but they might want to get an idea of whether their site is a potential issue for people who live nearby (if people live nearby)
Not deliberate in this case, someone apparently doesn't know the ramifications of placing a reverse band dish next to a DBS uplink.
I’m not talking about what number is displayed on the screen.
When aligning a regular LNB, I usually lock in around -27
When aligning with a reverse band it’s -37 or -36
How about Just put all international on 119 after they get rid of SD locals in the next several months
When you say "regular LNB" do you mean the old 8 channel analog SWM, right?
The digital SWM amplifies each SWM channel separately, so they all end up at the same level. Since there is up to 10 db difference between the strongest and weakest transponders as received, the analog SWM had to amplify everything by enough to insure the weak ones were at the desired output level. Thus you end up about 10 db stronger when measured overall, since it was amplifying the weak transponders, the strong transponders, plus the noise between channels / unused SWM channels by the same amount.
When measured as a single composite reading it appears the analog SWM is at a much higher output, but that extra output strength is smoke and mirrors. You won't get its benefit when you tune a channel on one of the weaker transponders - you may be worse off, in fact, because the noise has been deliberately amplified.
Because they'd have to go back and install an SL5 for every international customer. That makes even less sense than putting them on reverse band. Plus they'd have to launch a new satellite to 119 when the current one runs out of fuel, which may be as early as 2021. That's obviously not happening, so 119 is almost certainly going away along with 110, and there will no longer be any use for SL5 LNBs.
- Status
