I recently received an email from a reader asking what license-free radios work over short distances in the mountains?
When it comes to license-free communications, you’re pretty limited in selection and capability. The most common are CB and FRS, although there are a couple others like MURS (limited to 2 watts and 5 channels of VHF) and the 49 MHz band (very weak and shares frequencies with baby monitors), I’m going to stick to CB and FRS though because I don’t have very much experience with the other two.
Neither of these are ham radios, and neither are “long range” in the context of being able to talk to people hundreds or thousands of miles away.
They both are capable of short range communication though. They both also have different characteristics that may or may not be of interest, depending on your intended use.
FRS – Family Radio Service
FRS radios are channel based, meaning they have specific frequencies they use on each channel. There are a total of 22 frequencies and these frequencies are not regulated as to which channel they have to be on, so they may vary between manufacturers and it’s always a good idea to test your equipment first.
FRS radios are limited in power to 2 watts on most frequencies, and .5 watts on a handful of frequencies.
FRS radios are also required to have a permanently attached antenna. These antennas are typically small and compact, and not very efficient, so that 2 watts of output power gets cut back even farther.
The frequency you’re using determines your antenna size. For these handhelds, an efficient antenna is about 1/4 wavelength long. In the case of these radios, that ends up being about 6 inches. Compare that to the antenna that comes on any unit you’re looking into and you should get an idea of expected performance.
These radios are usually very small and easy to carry. They are also relatively cheap, easy to acquire (as of today) and easy to use. With the inherit power limitations these radios are probably only going to be useful within a half mile or so in mountainous terrain. You may get better distance if you are across the valley from someone and they are within line of sight though.
Line of sight is an important concept in radio communications. Since radio waves behave a lot like light waves, the more visible two points are to each other the easier it will be for them to communicate to each other. With the limitations placed on FRS radios, this is even more important to keep in mind.
If I were looking for a good FRS radio I’d look into something like the Retevis RB17. It’s a simple, rugged radio. I like the larger size antenna versus the smaller ones on typical “bubble pack” FRS radios. It also has a very large rechargeable battery and uses the same Kenwood 2-pin accessory connector as the popular Baofeng ham radios. The channels are preset and cannot be changed on the radio, which is nice for keeping things simple if you’re using these in a group.
CB – Citizen Band
CB radios are also channel based, with a total of 40 channels. Whereas FRS radio frequencies are in the UHF band, CB radio frequencies are in the upper end of the HF band. This means their signal can sometimes be reflected by the ionosphere. While this phenomenon is interesting from a hobbyist point of view, it’s not typically consistent enough to be counted on for reliable communications.
CB is limited to 4 watts, 2 more than FRS, but because of its lower frequency it requires a larger antenna to be efficient at getting that power out. Remember that bit about having a 1/4 wavelength antenna? That’s about 8 1/2’ long for a CB.
While there are handheld CB’s, because of the requirement for a larger antenna these radios are better suited to being mounted on a vehicle or ran from a base station. If I were looking for a CB, I’d look for something like this President McKinley with Single Side Band.
While FRS antennas are permanent installations attached directly to the radio, CB radios all utilize external antennas with a coax feedline. This allows you to try different antennas similar to ham radio.
So there’s a brief introduction to license free radios. Depending on your intended use these may or may not be a good option.
Since these radios are license free, that means anyone can get one. And since they only operate on specific frequencies, that means it wouldn’t take much for someone to listen in on your conversations. In other words, they are not secure, but then again no radios are if you don’t possess the proper skills to use them.
I hope that helps shed some light on your question, and if you have more questions just send them my way, take care!