Hey, welcome to Fully Modulated. I'm Tyler, and today we're talking about ICE on antennas. Yeah, that's right. ICE. ICE ICE Baby. Just a quick uh disclaimer before we get underway. As usual, this podcast isn't connected or endorsed by any radio stations, broadcasting companies or other organizations. I've uh I've been in radio since 2014, a broadcast engineer since 2018, and a broadcast network engineer since 2025. This is just me sharing stories and insights about radio technology and broadcasting history. The things that I love. So winter is coming, and no, um, that's not a Game of Thrones reference. Or maybe it's already here, depending on where you're at. And you might be wondering, how do radio stations keep broadcasting when everything's covered in ice? Well, you're about to find out because ice isn't just an inconvenience. It can literally take a station off the air. Here's the thing when ice forms on an antenna, it doesn't just make it heavier. It actually changes how the antenna works electrically. Think about it. Your antenna is carefully tuned to work at one specific frequency. Everything is calculated, the length of the elements, the spacing, all of it. Now coat everything with ice, suddenly all those dimensions are wrong. Your antenna isn't tuned anymore. And some companies, when they put an antenna up, uh company that I worked with um once before, oh man, I'm blanking on the name, but they would slightly put the antenna just slightly out of tune. So when it did ice up in the winter, it would actually bring it closer to what it should actually be. Now, the worst part of this, when ice first forms, it's wet. And wet ice conducts electrically electrically. This is the absolute worst condition for the antenna. That wet conductive layer messes with everything. It can detune your antenna so badly that you're basically off the air. The reflective power, the visoir, gets so high that it trips the transmitter off. Later, the ice freezes solid and dries out. No, it's not quite as bad electrically, but now you've got a weight problem on your tower. Ice is heavy. And when I say heavy, I re I mean really freaking heavy. A bad ice storm can add hundreds or thousands of pounds to the antenna. And remember, this thing is way up on that tower, several hundred feet in the air, you know, maybe a thousand feet, acting like a giant sail in the wind. You can add all that ice, and then the wind hits it, and you're putting a massive stress on everything. The tower, the mounting hardware, the antenna itself, the towers have collapsed because of ice buildup. Antennas have been ripped off of towers. I mean, it can get serious. And then there's another problem. When the ice melts, it doesn't melt evenly. One side might be shedding ice while the other side is still coated. That creates an unbalanced load. It can twist the antenna, stress it out. Even worse, when big chunks of ice do start to break loose, they can fall and hit other equipment on the way down. Now, imagine a 50-pound chunk of ice falling from 500 feet up. As you can imagine, that's not going to end very well. Um so how do how do stations deal with this? Well, there are a few ways. In which one you use depends on, you know, a lot of things. But number one, money, your budget, your location, and obviously your equipment. The most effective method is heating, active heating. Some antennas have built-in heating elements, kind of like your car's rear window defroster, but way bigger. These systems use electricity to warm the antenna and prevent you know, prevent the ice from forming in the first place. The fancy ones have automatic controls. You know, you know, think temperature sensors and moisture sensors. When it gets cold and maybe a little wet, boom, the heaters kick on automatically without any input. Now, those type of systems, they're not cheap. Not to buy, not to install, not to run. We're talking kilowatts of power just to keep the antenna warm. But for the big guys, the big stations, for stations and places that get brutal winters, you know, think Minnesota. It's worth it because going off the air will cost way more money than running those heaters. You can also heat antennas a you know a couple different ways. Um electric is the most common. Heating elements running along the antenna structure powered from the transmitter building. Some big satellite dishes used forced air. Heated air blowing across the dish can be electric or gas. Works great for large surfaces, but it's more complicated to maintain. Now, not every station can afford heating systems. So there's another approach. It's called radomes. A radome is basically a cover that goes over the antenna. The name came from radar dome. Radome, if you didn't guess that. It's made uh it's made of uh material that it's it's transparent to radio waves, but keeps the weather out of it. Like a jacket for your antenna. Radarms uh radomes are really common on uh satellite editions and smaller directional antennas, but for FM antennas, you sometimes see those uh fiberglass tubes that enclose the antenna elements. The advantage is the radom keeps snow and ice from touching the antenna directly, so you don't get that electrical detuning problem. It's passive, no electricity is needed, lower cost to operate. But radomes, they come with cons too. They're expensive to buy and to install. They add wind load even when there's no ice. And if ice does build up on the outside of those radomes, it stays there. Unlike a heated antenna where the ice melts off, a radome just sits there with ice on the outside until it warms up. And a harsh winter, that could be weeks or maybe months. There's also a middle ground solution. There's a middle option. Coatings. Hydrophotic coatings make water uh beat up and roll off instead of sticking. Like raineks for your windshield. These can help delay ice formations, but um, you know, they're not a complete solution. They're expensive. They wear off from sun and weather, so you have to reapply them every so often. And in really bad conditions, they can still get overwhelmed. Other coatings like Teflon or PVC-based stuff, they've you know, they've been tried a few times, mixed results basically, out of it. They they might help uh you know a little bit, but nothing completely prevents ice in all conditions. So coatings are usually used with other methods, not by themselves. Now, here's where design comes in. Some antennas are built to be more resistant to ice. One way is using fatter elements. When you have a thick antenna element, ice doesn't change the diameter as much as um, or I should say, doesn't change the diameter as much percentage-wise. Think about it. If you've got uh you know a thin quarter inch element and you add a quarter inch of ice, you've tripled the diameter. But if you've got a two-inch element and you add a quarter inch of ice, you only increased it by about 12%. Um the fat element, it's gonna be less sensitive to the change, basically. Another uh clever trick is tuning the antenna slightly high, like I mentioned before. Um so if you're on 95.5 megahertz, you tune it for 96 megahertz. Normally, this causes like zero performance loss. But here's the cool part. When ice forms, it makes the antenna elements electrically longer. That brings the frequency down. So as ice builds up your antenna, it actually tunes itself closer to the you know, closer to your actual frequency instead of further away. The performance degrade, you know, it degrades way more gracefully. For really important sites, um, you know, some places use multiple antennas. If one gets ice build up really bad, the others pick up the slack. It's not perfect, but they're all they're all in the same weather. I mean, uh, but if the icing isn't perfectly even, even backups could help. Then there's the brute force approach. Just let it happen. Some stations, especially smaller ones and areas that don't get bad winters, they just accept it. They'll have reduced coverage for a few days, or you know, you know, a few days out of the year when it's really bad, they'll monitor everything, make sure nothing's getting damaged, and just kind of wait it out. When it warms up, the ice melts and they're back to normal. And finally, there's manual intervention. I've heard stories of engineers climbing towers in the winter, which I do not recommend to remove ice and check for damage. Now, like I said, that's dangerous work. Tower climbing is already one of the most dangerous jobs in broadcasting at ice, and it's exceptionally worse. This is a this is last resort only. Only when there's no other choice, and only by people who really know what the hell they're doing. The reality is ice management is just one of many challenges that we as broadcast engineers face. In summer, we worry about lightning and overheating. In winter, it's ice and snow. Year round, there's maintenance, failures, power outages, all kinds of stuff, network loss. I mean, anything, any number of things can go wrong. But that's that's what makes this job interesting, right? At least for me. They're constantly probably problem solving, adapting, finding ways to keep the signal going no matter what. Every station's situation is different. Different location, different tower, different equipment, different budgets. There's no one solution that works for everybody across the board. The stations that do it right, they probably plan ahead. They invest in the right equipment for their situation: heated antennas or radomes, ice-resistant designs, whatever, whatever works for their budget and their situation and their location. They have backup plans, they maintain their gear, they have engineers who understand the systems and can respond fast when things go wrong. So the next time you're listening to the radio during a winter storm, take a second to appreciate what's happening behind the scenes. There's an antenna way up on a tower somewhere, either being heated, protected by a radome, or just tough enough to handle whatever ice is forming on it. And if you do lose a station during the storm, well, now you know why. It's probably ice. The engineers are probably already working on it, or they're waiting it out. And as soon as they can, they'll get it back on the air. That's what we're here for. That's what we do. Thanks for listening to Fully Modulated. If you enjoyed this, please follow the show on Apple Podcast and Spotify and leave a review. It really helps other people find the show. I think. I don't know. Nobody's ever shown me the data on that. If you have uh if you have questions or ideas for future episodes, email me, Tyler at fully modulated.com. You can also find the show on Facebook at Fully Modulated, on Instagram at Fully Modulated Pod, and on Bluesky at Fully Modulated.com. This is Fully Modulated. I'll catch you next week.