Ham radios are fantastic communication devices in SHTF situations where the internet, phone lines, and our other forms of communication just won’t work. But, just how far can you talk with your Ham radio?
While some Ham radios advertise up to 36 miles of range, you can realistically only get about 2-18 miles of range depending on the specific unit you’re working with. However, the actual range you can get from your Ham radio in the real world can vary substantially.
Like anything Ham radio-related, the answer to how far you can communicate with your radio isn’t as simple as it might seem. The world of Ham radio is notorious for being a bit confusing to newcomers, so learning the basics, like how far you can talk with your radio, can easily seem like an insurmountable task.
In fact, there are a whole lot of “ifs, ands, or buts” involved with giving estimates for the range of any radio and Ham is no exception.
To demystify the concept of Ham radio ranges, up next, I’ll walk you through everything you need to know about what affects your transmitting distance so you can better understand what to expect from your own radio.
What Affects Ham Radio Range?
As I’ve mentioned, Ham radios have an average range between 2 miles and 18 miles. But, if you’ve recently purchased a Ham radio (especially a handheld unit), the manufacturer might claim that you can get substantially more range than 2-18 miles. In fact, many 2-way radio units claim as much as 36 miles of range.
So, what gives? How far can you talk with a Ham radio?
The fact of the matter is that the range stated on a radio unit is the “theoretical range.” But, we rarely, if ever, experience conditions on Earth that are as perfect for radio transmission as what’s used to calculate “theoretical range.”
This means that the question of maximum Ham radio range isn’t easy to answer because there are a whole lot of different factors that affect how far you can communicate with a radio.
Therefore, instead of telling you that you can simply expect a range of 2-18 miles with your Ham radio and leaving the conversation at that, here are 4 key factors that affect your transmitting and receiving range.
Signal Type & Frequency
Within the United States, Ham radio operators can use 26 different “bands” or groups of frequencies with their radios. According to the National Association for Amateur Radio, this includes everything above 1.8 Megahertz to 275 Gigahertz. This is a pretty wide range that technically covers HF, VHF, UHF, SHF, and EHF frequencies.
In fact, depending on the band that you use, you can talk with your friends on the other side of town or communicate with people across the world.
So, choosing the right frequency for your communications will have a major impact on your range. That being said, the majority of Ham radio operators stick to VHF and UHF frequencies.
Here’s what you need to know about how choosing to use either VHF and UHF affects your range:
VHF, or “very high frequency” radio bands are between 30-300MHz. These bands are frequently used by maritime, military, emergency, and air traffic control systems. It’s also used for FM radio broadcasting (AM radio actually uses HF or “high frequency,” which is 3-30 Mhz).
The main benefit of VHF is that it has longer wavelengths than UHF. This means that they can generally travel further and with less interference.
If your main goal for your radio is to transmit as far as possible, you might be saying, great, sign me up for VHF!
However, the disadvantage of VHF is that it’s not as effective in areas with buildings or other tall obstacles. Therefore, VHF is best for use in long-distance communications in outdoor areas where the receiving radio is more or less within the line of sight of the transmitting radio.
UHF, or “ultra high frequency” radio bands are between 300MHz and 3GHz, so they’re one step up in the frequency ladder from VHF. This means that they have shorter wavelengths and more energy than their VHF siblings. UHF is more commonly used for cell phones, GPS, Wi-Fi, Bluetooth, and walkie talkies.
When compared to VHF, UHF has the added benefit of being more reliable in areas with lots of buildings or tree cover. Conversely, UHF is less effective over long distances, especially in mountainous areas.
UHF vs VHF: Which To Choose?
What this means for you, when it comes to Ham radio range is not that you should definitely choose VHF over UHF because VHF is better over longer distances. In fact, to maximize the range of your radio, you need to operate on a frequency that’s appropriate for your location.
So, if you live in a rural area with lots of open space, you’ll likely get better range with VHF. In an urban area, however, your range will generally be better if you opt for UHF instead.
The height of an antenna has a major impact on the amount of range that you can get with your Ham radio. This is especially true at frequencies above 2MHz, as anything above this frequency works on line of sight transmission and can’t bend around the curvature of the Earth.
Therefore, your maximum communication range with a Ham radio is the distance to the horizon line based on your antenna height.
With that in mind, your distance to the horizon (in miles) is calculated at:
D = √H x 1.415
where D is the distance in miles and H is the height of your antenna in feet.
So, someone using a handheld radio that’s positioned at 5’ off the ground would have a theoretical horizon of 3.16 miles. Meanwhile, a fixed station antenna that’s 20’ high would have a theoretical horizon of 6.33 miles.
Increasing the height of your antenna is one of the easiest ways to extend your range. However, your communication range is limited not only by the height of your antenna, but the height of the antenna that’s receiving your transmissions.
This means that two radio stations that are transmitting with each other will be able to communicate over a longer range than two handheld radios. As we’ll see, however, this “theoretical horizon” distance is just that: theoretical.
Therefore, you can think of this calculation as an indication of the maximum possible communication distance rather than what you should expect every time you use your Ham radio.
Radio signals aren’t very good at traveling through solid objects, such as mountains and buildings. Indeed, trying to talk through obstacles is a sure-fire way to reduce the range of your radio communications.
This is why we almost never communicate as far as our maximum theoretical range says we should be able to. Every time a radio wave has to pass through an object, the strength of the signal decreases, thereby shortening your overall range.
As I’ve mentioned, UHF frequencies are better at travelling through buildings and other objects in urban environments because of their higher energy wavelengths.
What this means for you, as a Ham radio operator, is that to maximize your range, you need to choose the appropriate frequency for your location. Additionally, it’s important to understand the limitations that your surrounding terrain has on your potential communication range.
The final factor I’ll touch on when it comes to Ham radio range is the “strength” or “power” of your radio. Signal strength is measured in watts, and there’s a big difference in strength between a handheld unit and a typical commercial radio station.
While commercial stations will broadcast between 50,000 – 100,000 watts, handheld radios usually have just 0.5-5 watts of power. There are also laws about the signal strength of amateur radios, and Ham radios can generally have up to just 5 watts of power.
Simply put, the higher the signal strength (or watts) of a radio, the further it can travel. So, a 5 watt Ham radio is going to be able to transmit further than a 2 watt Ham radio with the same antenna height and in the same terrain.
So, Just How Far Can I Talk With My Ham Radio?
At this point, hopefully it’s clear that the answer to this question isn’t as simple as it may seem. In reality, the range of your Ham radio depends on the frequency you’re using, the height of your antenna, the obstacles and terrain around you, and the wattage of your radio, among other factors.
So, when you buy a radio unit and it claims to have a range of 36 miles, remember that this is a theoretical range in ideal conditions and not the norm. What’s more important is that you understand what affects the range of your Ham radio and what you can do to improve your range for better performance when SHTF.