Frequently Asked Questions About Satellite LNB and Multiswitches

How does an LNB work?

There are 32 transponders on the 101-degree satellite (main satellite) that send channels. They are numbered 1-32. Each transponder sends a group of channels. An LNB on a satellite dish can look at either odd or even transponders at any given time. It cannot see both at the same time. If you change the channel to one that is on an odd transponder, then the LNB switches to look at the odd...if you change to a channel on an even transponder, then the LNB switches to look at the even.

How does the LNB know which side (even or odd transponders) to look at?

This is done by the 13 or 18 volts that your receiver calls out for depending on which channel is going to be viewed on the TV.

What is a Dual LNB?

A Dual LNB is just two LNB's in one housing. Each connection can operate independently of each other so you can have two receivers, and each one is looking at different channels on different transponders. They both look at the same satellite (101 Degree satellite). A single LNB only has one coax connection and cannot be used with more than 1 DIRECTV receiver.

The 18" dish had a Dual LNB that looks at one satellite. The 18x24" dish has TWO Dual LNB's and is set up to see two satellites... the 101 degree and the 119. The 119-degree satellite sends additional programming such as foreign language programming and HDTV programming.

Another option is to use two Round 18" dishes, one pointed at the 101 degree satellite and the other pointed at the 119 satellite to do the same as the Elliptical dish. This gives you the same functionality but is not very attractive for your client’s home. You would connect the four cables from the two dishes to a multiswitch and then connect to multiple receivers.

Can I use a splitter to add more receivers or add dual Tuners to my DIRECTV DVR?

No, this is where multiswitches are used. Remember that if you try to split an LNB, you will have two receivers fighting each other for signal and ultimately both receivers would only see have of the channels.

I heard I can use two round dishes, how do I do that?

Remember the only thing special about the oval dish is that it has two LNB's looking at different places. So, if you have two round dishes, one pointed at 101W, the other at 119W, and you use the same kind of multiswitch that comes with the oval dish, then you see the exact same thing. There's nothing inherently special about the oval dish except that it's pointing at two places in the sky. A lot of people use two round dishes to get a minor signal improvement, or more frequently because getting a couple of round dishes can be cheaper. All you need is a 4xN or 5xN multiswitch and to aim the things the right way.

What is SAT-C Kit used for?

A Sat-C kit is a special adapter available as a kit to receive the 110W and comes with everything to need to hook it up to the oval dish. It goes in between the other LNB's. It's also a special LNB, so you can't use it as a single LNB or regular Dual LNB. Also, a regular single or dual LNB will not work as a Sat-C LNB.

What is a multiswitch and what is it used for?

A multiswitch takes the input from both of the LNB's (both cables from a dual LNB dish have to be connected to the multiswitch)...it then locks one of the LNB's to always look at the even transponders and the other LNB to always look at the odd transponders. This is why a multiswitch only works with Dual LNB’s and not single LNB's. The switch then has multiple outputs to receivers (4,8,etc). When you connect the receiver to the multiswitch, the switch determines which of the two LNB's the receiver needs to look at depending if it needs to view odd or even transponders. When you change the channel, the switch then swaps your connection to the other LNB when needed. With a multiswitch, the LNB's never change which side they are looking at.

What about multiswitches with Elliptical dishes?

If you have the oval dish with two "dual LNB’s" (4 cables), each of the Dual LNB's look at different satellites (101 degree and 119 degree satellites). A multiswitch is needed to see the second satellite. A multiswitch comes with the dish and is usually have 4 outputs. Multiswitches for elliptical dishes need to have 4 inputs so it can switch between the 4 LNB’s rather than the 2 in the explanation in question #1 above.

If my receiver sends voltage changes to switch between odd and even transponders on the 101 satellite, how does it tell the multiswitch that it wants to see the 119 satellite?

The receiver sends a 22khz tone over the cable along with the voltage change so it tells the multiswitch that it wants either odd or even transponders by the voltage and that it wants the 119 by sending the tone.

What is the 2x4, 2x8, 3x4, 3x8, 4x4, 4x8, 5x4 & 5x8 designations mean when referring to a multiswitch?

The first number in the number of inputs from the dish (or antenna) the switch has. The second number is the number of outputs the switch has.

Can I connect two Multiswitches together (cascade one to another) to add more connections?

If you are using an 18" Dual LNB dish, then you could "cascade" two switches together. You could take a 2x4 switch and have 2 of the outputs feed the inputs of another 2x4 switch to give you a total of 6 outputs. There are many issues that you have to be aware of though; length of cable, quality of multiswitches and whether they are powered or non-powered may affect. If you have an 18x24" elliptical dish, it is a little more complex, but can be accomplished.

As mentioned above, the receiver will send a 22khz tone to tell the multiswitch that it wants the 119-degree satellite. This tone is only used by the multiswitch and is not sent back up to the LNB's

There are switches designated as "cascadable" that WILL send that 22khz tone upstream, thereby allowing you to connect it in series with another multiswitch (such as a built in one on the dish). These are more expensive than non-cascading models. The other way is to get "tone generators" which go on the two cables designated for the 119 satellites. They go inline between the two multiswitches (or between dish and multiswitch if you have the built in multiswitch on the dish). These tone generators put the 22khz tone on the line so that the 1st multiswitch (or built in one) sees the tone and puts that line over to the 119 satellite

There are SO many different multi-switches with a wide range of prices. Which one is right for me?

There are 3 main types of multi-switches:

[A] Non-Powered mechanical multi-switch - Cheapest in price. Has mechanical switching mechanism that is controlled by the power coming off of the DIRECTV receiver. The DIRECTV receiver changes voltages on the line depending on which transponder group it wants to look at. This multiswitch uses that voltage to move the switch. 

[B] Powered mechanical multi-switch* - Mid range in price. Has a mechanical switching mechanism. It uses the voltage changes from the DIRECTV receiver to determine what it should look at, but uses it's own external power to control the switch. Examples of these are Channel Master and Terk multiswitches.

[C] Powered solid-state multi-switch* - Most expensive. Completely solid state-no moving parts. Reads the voltage changes from the DIRECTV receiver and electronically routes the signal to the correct LNB. Examples of these are Tradewind, Zinwell, Spaun and Trunkline.

How many inputs do I need?

If you have an 18" dual LNB dish, you have 2 outputs from the dish, therefore only need a "2 x n" switch meaning 2 inputs from dish and "n" output (to be determined at next step.

If you have an Elliptical dish (or 2 18" dishes looking at different satellites), you will need a "4 x n" switch meaning 4 inputs (from dish) and "n" outputs. 

You will also see switches listed as "3 x n" or "5 x n"...This just means that there is an extra input for an off-air antenna. These switches allow you to combine an off-air antenna signal onto the same RG6 cables as your DIRECTV signal and split it out at the TV end. This saves you valuable cabling issues since you will only have to run 1 cable to a receiver instead of 2 (or 2 cables instead of 3 in the case of DIRECTV DVR’s)

How many outputs do I need?

This all depends on how many DIRECTV receivers you have. You need 1 output for each receiver. In the case of the DIRECTV DVR, you need 2 outputs for each receiver. If you have two DIRECTV DVR’s, it would max out a 2x4 or 4x4 switch. Once you max out a switch, you cannot split to any other receiver and must get a new switch if you need to expand.

Non-powered, Powered/Mechanical, Powered Solid state, Amplified multi-switches... which one do I need?

Well, that depends on your budget and your setup. If you have very long cable runs (greater than 100 feet), you should definitely get a powered switch and better yet, a powered/amplified switch. A non-powered switch may work, but since it depends solely on the voltage of the receiver to move the switch, the voltage loss in long cable runs could make the switch unreliable. In the case of long cable runs, we recommend a switch like the Tradewind.

How do I get the R-15 into stacked mode?

Push and hold the Active Button and the Right arrow button at the same time.  This will get rid of the setup guide.  Then go to LNB setup.  select stacked LNB and push select.  Then go to done.

On the D-11 receiver:

Push and hold the guide and down arrow to get out of the guided setup.  Then go to the menu and do a setup.  dish setup.  then auto detect.  this could take up to 10 min for the process to work.  after the auto detect you should be able to watch TV.
 
Courtesy of PACE Electronics

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