NICE AND EASY: What is line of sight and how much do I need?

We’ve talked about line of sight before. Somehow, it seems like a hard concept to imagine, so let’s take it really simple. Point yourself at something (like the sun.) Is there anything between you and the sun? A tree, another building perhaps? If you can see the sun (and for gosh sakes don’t stare at it) you have a clear line of sight to the sun. If you can kind of see the sun, you have an obstructed line of sight to the sun. If you can’t see the sun, you have no line of sight.

How does line of sight work with satellite and antennas?

Line of sight is critical when aiming satellite dishes and antennas. With satellite dishes, only a clear line of sight will do because the satellites are so far away. With antennas, you can sometimes get away with an obstructed line of sight because the signal is stronger.

It is generally easier to get good line of sight with an antenna. The beam width of an antenna is much wider. In other words, you can aim an antenna up to 15 degrees away from the towers and it still works in most cases. With satellite you need to be pointing very close to perfect. With a satellite, you also have to consider another factor: elevation.

What effect does elevation have on satellite TV aiming?

With antennas, you set the antenna level in almost every case. With satellite TV aiming, you’re setting the antenna to look at a fixed point in the sky. You’re generally aiming for a point 22,000 miles above the equator. Depending on which satellite (or satellites) you’re trying to receive signal from, you’re aiming at a point somewhere from 61 degrees to 129 degrees west longitude.

The fact that you need to tilt the dish up makes a lot of difference for line of sight. In southern areas, dishes are generally aimed upward. However, as you get further and further north you need to tilt the dish down more and more. Satellite TV users in the southern states rarely worry about trees or homes impeding their view, but from Maine to Montana, it’s a much bigger concern.

What if you don’t have good line of sight?

Anything you put in front of a signal is going to cut the power of the signal. Even air cuts the power of the signal. If you put an antenna inside, its efficiency is cut by about half.

What can you do about line of sight issues? The best answer is generally to go up,up, up. The higher you go, the more likely that you’ll find a clear line of sight to whatever you’re looking for. You can start with a tall pole, but if you really want to address line of sight issues, you’ll need a tower.

Luckily, you have a friend in the business. Solid Signal can quote a custom tower for you including virtually everything you’ll need. If you’ve never put up a tall tower, you’ll probably want to find a local contractor to do it, but for everything else just call 888-233-7563 for the best advice, the friendliest people, and the timeliest quotes.

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 10,000 articles and longform tutorials including many posted here. Reach him by clicking on "Contact the Editor" at the bottom of this page.