How to Hook Up Multiple Satellite Receivers
A Multiswitch is needed to connect more than two receivers to a single rooftop satellite dish. This product is more than an ordinary cable splitter that simply takes all the signals on the cable and divides it into multiple paths. Inside the multi-switch are relays that will allow the satellite set-top box to receive the two different types of signals coming from the satellite in space. The satellite receiver will 'tell' the multi-switch which type of signal it needs for the channel you want to watch and it will pass the appropriate signal to the receiver.
Multiswitches are available in many configurations depending on the number of outputs you need and some have up to five inputs for multiple Low-Noise Block down-converters (LNB's).
Dual LNBYour rooftop dish antenna MUST have a dual LNB for a multi-switch to work properly or you will cause problems between the receivers. A dual LNB will have connections for two coax cables. A single LNB will only have one coax connection. A dish antenna with a single LNB can easily be upgraded to a dual model by replacing only the LNB portion of the antenna. We offer a Dual LNB Feed horn on our website that fits any brand of DSS antenna. Replacement is as simple as unscrewing the old and installing the new one and it can all be done without affecting the alignment of the antenna.
Active vs. Passive Multiswitches
The terms should really be Powered and Unpowered multi-switches. An un-powered multi-switch will rely on the power from each satellite receiver to run the multi-switch and the LNB's up at the dish antenna. Most of the newer receivers made after 1990 can supply enough power to run the multi-switch and the LNB's electronics. Some of the first and second generation receivers made in the mid 90's have more of a problem with multi-switches. Some people have commented that the un-powered tend to wear out faster and have more problems because of current flow through the relay contacts.
A powered multi-switch may have its own power supply to operate the LNB's and the switch's electronics. It only uses the power from the receivers as a way of telling which signal it needs to switch through from the dish to the receiver. An external AC adapter will either come with the multi-switch or it will be sold separately. With passive multi-switches, some users have reported difficulties using them with some brands of satellite receivers. It turns out that some satellite receivers can't provide enough voltage and current to drive both the multi-switch and the LNB. With an active multi-switch, there is never any question that it will work with a group of satellite receivers.
Some multi-switches will also pass the over-the-air (an un-amplified) outside antenna or cable signal to the ports. On the input side of some multi-switches, there is an antenna jack. If the multi-switch has this input, the same cable that carries satellite signals from the dish can also carry regular VHF/UHF from a roof-top antenna or cable TV service. At the satellite receiver, a Diplexer will split out the satellite and antenna signals. Click on the graphic to see a larger diagram of a system using a rooftop antenna and diplexers. Using this feature and a Rooftop Antenna, you can receive local channels for free (just like TV use to be!).
For those users who need to pull-down signals from more than one satellite, we have a Multi-Switch With Five Inputs (one for the VHF/UHF antenna and four for the satellite dish.) You may need this type of multi-switch if you have an oval-shaped antenna that has multiple LBNs. This type antenna is becoming more common as service providers use more than one satellite position to deliver their service. The trend in the industry is to deliver more channels (or content as they call it), but each satellite slot can only deliver a limited number of channels. To add channels for HDTV, Spanish language programming, and local television stations, service providers are requiring equipment that can receive signals from multiple satellites slots in space. Each satellite slot, (common ones are 101, 110, and 119) will likely have multiple "birds" operating. For example, as of this writing, DIRECTV has four satellites (3 active and one backup) at the 101 slot providing their core programming to the United States.
If your dish antenna has four coax cables coming down from the roof, you will need a five input multi-switch. These multi-switches cost a more than the basic ones discussed above since they must do the more complicated switching. Click on the graphic to see a larger diagram.
If all this wiring sounds like a nightmare consider adding satellite distribution to a structured wiring center. These network centers handle all the wiring for television cable and communications. Some models have the ability to handle satellite signals.