TIP: Use the smallest splitter possible

Admit it, we all have a tendency to use large splitters when we could use small ones. Even though the large ones cost more, we put them in because we want to future-proof our systems. Since DIRECTV rolled out their SWiM system that allows the line to be split multiple ways, this has become even more common.

There’s a good reason not to split the line more than necessary: line loss. Even a properly terminated splitter loses signal. In fact, the loss from a single 1×8 splitter can be up to 10 times greater than a 1×2 splitter. This means that you’ll have problems on longer lines especially in areas where rain fade is common.

If you’re an installer, you generally don’t have a choice. In fact it’s a good idea to leave the customer with one unused port, just so they can do a little bit of the work themselves if they want. However, some installers have been known to put a 1×4 splitter after a 1×8 splitter just because it’s what they had in the truck. In this case it cost the customer another truck roll and a lost day of pay when the only problem was that the splitters were too much for the job.

If you’re a DIY’er think about the absolute minimum you’ll need to run the system you have. Put splitters where you can reach them later so that you can easily upgrade from a 1×2 to a 1×4 if you need. Home installations hardly ever need a 1×8 as they won’t have 8 receivers very often. More likely they will have DVRs which only need one line to run 2 tuners. In homes, a 1×4 will usually do just fine. If you plan on splitting the line after a long run, use a 1×2 close to the dish and another 1×2 (or 1×4) where you need it.

Our expert VOS writes:

SWiM has a useable loss between the SWiM and the farthest receiver of about 30 dB.
If you don’t use ANY splitters, this comes out to about 300′ of RG6.
Add ONE 2-way splitter and you’ve lost 50′, so you’re down to 250′.
Use ONE 4-way splitter and down another 50′, to 200′.
Use ONE 8-way splitter and you’ve down to 150′.

Following this:
ONE 8-way splitter and having to add a 2-way down stream, leaves you only 100′ of total coax between the SWiM & the receiver.
Should you [foolishly] use ONE 8-way and a 4-way, you’re down to only 50′ of coax [loss] before the receiver starts showing loss of signal.

All used ports need to be terminated, but this just means you wasting signal into a 75Ω resistor, instead of sending it to a receiver.

Always try to use the best size splitter for the need. Better to be able to add a 2-way downstream, than waste all the signal power in an over-sized splitter with a lot of loads/terminations.

Splitter do give you the flexibility of distributing them where you need them, which can be more helpful than home runs to a multi-switch.

All splitters are built upon a 2-way, so:

About the Author

Stuart Sweet
Stuart Sweet is the editor-in-chief of The Solid Signal Blog and a "master plumber" at Signal Group, LLC. He is the author of over 8,000 articles and longform tutorials including many posted here. Reach him by clicking on "Contact the Editor" at the bottom of this page.