Line Accessories

Because Dish Network has been around so long, they've sort of boxed themselves into a corner when it comes to signal distribution. All of their programming could be carried on one satellite, received with a single bandstacked LNB, and distributed with a splitter, but they've gone in a lot of completely different directions and have to support a diverse array of orbital locations, switches and receivers. Some of the switches are kind of complicated and require other accessories to function properly. Here's how they work.

Diplexers

A diplexer takes an L band satellite IF signal (950-2150 MHz) and combines it with a VHF/UHF over the air or cable TV signal (5-900 MHz), or vice versa. A pair of diplexers, placed at the ends of the cable allows both signals to be combined onto a single cable and separated at their destination. These have been around a while, to let people combine signals from an off-air antenna with their satellite feed, but Dish Network uses them for "backfeeding".

A dual tuner receiver like the 322 or 222 uses a UHF output (25 MHz to 900 MHz) to distribute programming to a second TV. To save on a cable, that signal can be combined with the incoming satellite IF signal and separated at the point where all of the home's cabling comes together to be sent on to its destination TV.

Separators

In a Dish Pro Plus system a dual tuner receiver is fed with a single cable, rather than the two that would be needed for Dish Pro or Legacy. The way that this works is that the switch sends the signal for one tuner on the low band, 950-1450 MHz, and the second tuner's signal on the higher band, 1650-2150 MHz. The separator is simply a filter that accepts both bands, and outputs 950-1450 to tuner one and the 1650-2150 to tuner two. It also allows power and DiSEqC signals to the switch from tuner one only.

Triplexers

A triplexer is simply a separator and diplexer combined into one device. It's more or less a labor saving thing, since technicians used to have to install a diplexer and a separator.

Splitters

Splitters aren't normally used for satellite IF distribution, except in a few rare cases. A splitter may be use to connect a single bandstacked LNB to multiple receivers or switches, or to connect a single polarity of a standard LNB to multiple receivers or switches. Splitters are frequently used in new Dish Network installations, however, to route UHF signals from a dual tuner receiver to multiple receivers, and to connect multiple Joey receivers in a Hopper/Joey system.

Taps

A tap is a new addition to the Dish Network lineup. It functions almost the same as a diplexer, except that the input and output pass both UHF and satellite IF, while a third port passes only UHF. It's used in the line between the dpX node and the Hopper to connect Joeys or a Hopper Internet Connector.