WARNING: Don’t paint the satellite dome on your boat

The other day, I was talking to one of the marine specialists at Signal Connect. These folks are experts in helping people get the best entertainment experience while they’re out on the water. This person was telling me all about a customer who was having problems with their satellite TV system. It didn’t take very long before we got down to the source of the problem.

The customer had recently cleaned up their boat and along the way, had painted the satellite dome. A lot of these satellite domes have been on boats for well over 10 years and I can understand wanting to make them look nicer if they’ve begun to look old. The problem, as this customer found out, is that painting the satellite dome stops the signal from getting in to the electronics inside. Here’s why that happens

The color theory we just have to get through​


In order to understand the problem we have to understand a little bit of color theory. It can be a pretty dense subject, and I’ll try to get through it quickly.

When you’re talking about an object that gives off its own light (like a light bulb) that’s emissive color. In other words there’s radiation coming from the light bulb that reaches your eyes. Everything else, that’s reflective color. In other words, you don’t see it unless there’s an emissive light source like the sun or a light bulb. The radiation from the emissive light source bounces off the reflective thing and then goes to your eyes.

The color you see depends on what happens when that light hits a reflective source. Some of it is absorbed or passes through, and some of it is reflected. It’s a lot of science but it goes like this. If you’re seeing something white, then it’s reflecting pretty much all the light coming at it. If you’re seeing something black, then it’s reflecting almost none of the light coming at it. (I won’t get into how colors are formed, that’s a little more complex and doesn’t really have a lot to do with this article.)

However, there’s a lot more to radiation than just what you can see. Radio waves, cellular signals, all that is radiation too and it behaves the same way. Some materials reflect it and some materials absorb it or let it pass through. That’s why radio waves can pass through things like walls, even though visible light can’t.

All white things are not equal​


When something looks white to you, that’s because most of the visible light coming at it is bounced back at you. But, other forms of radiation like satellite signals might not bounce back. That’s how these satellite domes work. They look white to you, but the lower-frequency satellite signals pass right through. The plastic has been engineered that way.

When you use white paint, that paint has been formulated to reflect back visible light. It probably hasn’t been tested to see if satellite signals bounce back. So it could reflect back satellite signals too, and that’s what happened in this case. All the satellite signals were bouncing off the painted dome and none of them were getting to the antenna inside.

Making matters worse​


Again, there’s a lot of dense science involved here but making white pigment is pretty hard. Remember how, when you were a kid, you were disappointed that the white crayon didn’t work as well as the others in the box? It’s because, well, science. Generally speaking if you use a “white” pigment, it’s going to look a little yellow. Pretty much everything in nature that we think of as pure white is really kind of yellow compared to the unnatural “pure white” we get from LED lights.

In order to make you feel like things are “really” white, two extra ingredients are used in paint, paper, and even laundry detergent. The first is called optical brightener, which actually shifts the frequency of the light more toward the blue side of the spectrum. This makes things seem “whiter” to use. The other is some sort of reflective material like mica or metal flakes. These are really small particle, much smaller than a grain of sand, so you don’t see them or feel them. But they can be added to white paint to make more of the radiation bounce back.

Obviously, optical brighteners and reflective materials are deadly to satellite signals. Messing with the signal that way is just going to stop your system from working. So, when you really think about it, painting a dish is going to be a very bad idea indeed

What can you do if the dish looks old?​


The best thing to do with a satellite dish is to clean it with mild detergent like dish soap. Don’t use laundry detergent because it could have optical brighteners. Use a rag and some dish soap to clean the dome up. Or, if it’s really unsightly, your Signal Connect representative can help you with a replacement outer dome. It’s also a great time to look at what’s available with newer satellite domes that might pick up even more channels.

If you need help with your satellite TV system at home, at work, on the road, or even at sea, call the experts at Signal Connect. We’re here for you during East Coast business hours. The number is 888-233-7563 and, if it’s after hours, just fill out the form below.


The post WARNING: Don’t paint the satellite dome on your boat appeared first on The Solid Signal Blog.

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Wait, you're talking apples and then suddenly switching to oranges. Domes and then dishes, without any transition.

Just as reflectively painting an over-dish dome may block signal, wouldn't a reflective paint either enhance or have no effect when applied to the dish, the reflector itself? There are dishes of all colors including black.
 
Wait, you're talking apples and then suddenly switching to oranges. Domes and then dishes, without any transition.

Just as reflectively painting an over-dish dome may block signal, wouldn't a reflective paint either enhance or have no effect when applied to the dish, the reflector itself? There are dishes of all colors including black.
Darker colors tend to absorb heat more than light or pastel ones. A minor issue in most situations with a mesh type satellite antenna. If you are talking solid type, there is much more connected surface area that can conduct heat buildup. White colors are probably the best for minimizing heat on any dish. The subject in this discussion was about painting a dome, and the problem was that painting a dome with anything can and usually will reduce its ability to pass satellite signals. We're not trying to pass a signal through a dish or a feedhorn cover, and in fact are trying to do quite the opposite when painting those items.
 

Where is the antenna on your phone anyway?

Can you hook a Gemini Air up to an AV receiver or soundbar?

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