Since DirecTV's beginning, they have pretty much used the same technique to get the signal from the dish to the receiver.
The receiver would use an internal data mapping: to match your requested channel to which "part" of the sat signal it can be found on.
The receiver would then use a combination between voltage and "tone" on the coax line to talk back to the dish (or multiswitch). That voltage and "tone" tells the dish which signal part to lock on to (and also provide it power to do it).
After the dish adjusts for the requested signal, it then sends that data stream down the coax line back to the dish... in a specific frequency.
And that specific frequency, is the major part that causes all the challenges with DBS technology. On a coax line, only 1 signal can occupy a frequency range. With each piece of the SAT signal, wanting to use the same frequency range... a single coax can only carry one part at a time.
There has been equipment designed and built, that will "shift" the frequency of one part of the signal to another frequency on the cable. That will allow you to use more of the frequency range of the cable.
This is called STACKING... as basically it stacks a piece of the signal on top of another piece of the signal. But you need some really expensive hardware to STACK all the pieces on to one cable... But even if you have the stacking, you need a piece on the other end to DESTACK that signal... so that solution gets expensive, and is still limited... As if there is a 9 or 10 parts... that requires new stackers and destackers....
Still with me? Multiple Sat Signal Pieces... one at a time on the cable, stacking...
Well now mix in Multiswitches...
Multiswitches are used to get more "feeds" for your additonal receivers in the house.
They work by "locking" onto the different signal parts, then they act like a dish does... listens for the receiver's requests... and then sends that piece down the line.
At the start multiswitches where expensive... but they they got cheaper... then more "pieces" of the SAT signal where introduced... which ment new multiswitches where needed... expensive, then cheaper... then more "pieces" of the SAT signal where introduced... ect
Okay... now to throw another wrench into it...
With the introduction of the dual tuner DVRs... you now needed not one.. but TWO coax lines running from either the dish or a multiswitch, to that DVR... in order to use both tuners... So that ment more wires... Bigger Multiswitches, or complex setups... more expense...
Now... include OTA for the additional broadcasts in the area... before, you could just diplex it it (which was basically STACKING)... well now with so many pieces of the SAT signal in the line... you can't diplex it in anymore, as that segment of frequency is now going to be used.
Still with me... confused? You have good reason to be..... it is confusing, and honestly... it took me a long time to understand it all, and there are times I still shake my head. Don't feel alone... Even 10 years later, there are still people asking why they can't just split their SAT signal feed.
To give you an idea... in my 3yr old house, I have over 4,000ft of RG-6 coax installed. And it wasn't by "accident". Since I knew what I was doing, and what I needed... I was able to have it done, before the walls where put up. But I am probably in the less then 0.01% of the people out there, that are building a new house and have a good understanding of the technology (even the "wiring" guy didn't understand why I was doing it), and willing to do it.
And even with all that planning... I still had an issue....... So what does this all have to do with SWM, and you... well... we are going back to ONE
SWM will bring us back to a stage where we can use a SINGLE wire and REGULAR cable splitters to get the signal all over your house, with in some limits though.
Where this is very helpfull as a house built in the 1980's designed for Analog cable, or a house built in 2007 with a builder that designed it for "cable" and not DBS, will be able to use this technology very easily.
SWM will also alow you to DIPLEX in your OTA signal again into the line, so you really can get to a SINGLE wire solution.
So let's brake it down: There are two major components to the SWM setup;
The SWM Module and a SWM compatible receiver.
We will discuss each of those seperately... First, let's talk about the receivers as it is the simplest to explain.
As of this writing; there is only ONE receiver that is production ready for SWM, that is the HR20.
DirecTV has just released their Standard Definition Non-DVR (BASIC) receiver, the D12. The initial software version for the D12 is not SWM ready, but the hardware is. A "relatively" soon to be released software version will enable the D12's SWM feature.
Also, you know those H20's... their hardware is also SWM ready, but the software isn't. In the H20's future software update, SWM will be enabled. (Yes, DirecTV has not forgotten about the H20s)
The R15 is not compatible with SWM, nor are TiVo's or Ultimate TV, or any other released receiver. That also includes D10's (which is the inside the Samsung Fliptop), D11's (which is the inside of the Humax LCD), and all previous generation of standalone receivers and DVRs.
SWM changes how the signal is carried on the line, thus on the same physical cable you can not have an SWM and a non-SWM system connected. At this time, there is no planned "converter" box to allow a non-SWM ready system to work with an SWM-signal.. BUT you do still have options, as I will explain later on...
SWM's are going to work on a class scale. This will help you and the installers install the appropriate SWM module and to understand the limitations with this setup.
There currently are TWO classes of SWM receivers:
SWM-1 and SWM-2 The key value is the # in that class.. either a 1 or 2
H20's and D12's are SWM-1
HR20 is a SWM-2
You will need to make note of that #, when you design and implement your FTM solution.
The SWM Module is a device that looks very similar to multiswitch.
DirecTV is initially going to have two versions of the SWM module:
A 5 channel model and an 8 channel model.
The 5 channel version is going to be the first one available, and the one I am going to describe below. When the 8 channel is ready, I will let you know the details on the chanels. But it is basically going to be just a bigger version of the 5 channel.
NOTE:There is an SWM version for MDU's and significantly larger solutions. For details on those, contact DirecTV's MDU information center, as they are not targeted for the home customer.
Your SAT Dish (or dishes), will connect to the SWM module in the same manner that you would connect a multiswitch. 4 Feeds from a 3LNB/5LNB plus the single feeds from up to two additional dishes (72.5 and 95).
The SWM module is WEATHER ready, and designed to be installed inside or outside. You can actually mount this device right behind your dish, so you only have to run one cable INTO the house. I mounted mine inside, since I was wired for it.... but another example, would be to pop off that cable box cover outside... take that one feed, and connect to the SWM module.
The SWM is POWERED. It get's it power from an external power inserter, that is included with the SWM. The power supply is NOT weather ready, so it will need to be installed in your home. Placement should be between ~15ft and 40ft to the SWM.
You basically connect it INLINE with the receivers... you do not have to run a seperate cable. Just ONE line.
On the 5ch version, there are two SWM outputs. These are the SAME SWM line, just internall split already... so if you need to send the signal two different ways from the get go. You only need supply power on the SWM #1 port, not both.
Also on the 5ch version, there are two LEGACY ports. These two ports can be used to connect older non-SWM ready equipment. They will function the same as the "old" technology, and all the rules and techniques that apply to the "old" technology.
So that are the "pieces"... how do you put it all together.
Recalling the last couple posts, some key information:
HR20 is a SWM-2
H20 and D12 is a SWM-1
5 Channel SWM
8 Channel SWM
The #1 rule of SWM: The sum of the classes can not exceed the number of channels.
So with a 5 Channel SWM you can connect:
2 HR20s, 1 H20
2 HR20s, 1 D12
1 HR20, 1 H20, 2 D12
So on... as long as the sum of the "class" is <= 5
With an 8 channel SWM... you could connect 3 HR20's and one H20, or 8 D12's to one line.
SWM lines can you regular coax cable splitters, no need for multiswitches.
To create "extra lines", you just need a regular coax splitters.
These splitters need to be rated for frequencies between 5 and 2000 mhz.
Also, if you don't use the "power supply", then you will need a power passing splitter between the FTM module and the first FTM enabled box.
In my main room: I have one line comming from the SWM. I then have it split, and then powering the two HR20s. So I don't need 4... I just need 1
You can also diplex in your OTA... the SWM doesn't support that in the module itself, but you can add it in at any point in the SWM line. So you really can have just one line running to your room.
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