Most of us carry cell phones with us almost everywhere we go. So much so that we often forget not just the usefulness, but even the joy, of having our own radios. For instance:
When traveling to national parks or other wilderness areas, family and friends can keep in touch even where there is no cell coverage.
It is a lot faster to just push a button and start talking than it is to unlock a phone, open the phone app, select a person, wait for the call to connect, wait for the other person to answer, etc. “I’m heading back.” “OK.” Boom, 5 seconds, done. A phone user wouldn’t have even dialed in that time.
A whole group of people can be on the same channel.
You can often buy a radio for less than the monthly cost of a cell plan.
From my own experience, as a person and a family that enjoys visiting wilderness areas, having radio communication is great. I have also heard from others that they’re also very useful on cruise ships (I’ve never been on one so I can’t attest to that).
There is also a sheer satisfaction in not needing anybody else’s infrastructure, not paying any sort of monthly fee, and setting up the radios ourselves.
How these services fit in
This article is primarily about handheld radios that can be used by anybody. I laid out some of their advantages above. Before continuing, I should point out some of the other services you may consider:
Cell phones, obviously. Due to the impressive infrastructure you pay for each month (many towers in high locations), in areas of cell coverage, you have this ability to connect to so many other phones around the world. With radios like discussed here, your range will likely a few miles.
Amateur Radio
has often been a decade or more ahead of what you see in these easy personal radio devices. You can unquestionably get amateur radio devices with many more features and better performance. However, generally speaking, each person that transmits on an amateur radio band must be licensed. Getting an amateur radio license isn’t difficult, but it does involve passing a test and some time studying for the exam. So it isn’t something you can count on random friends or family members being able to do. That said, I have resources on
Getting Started With Amateur Radio
and it’s not as hard as you might think! There are also a lot of
reasons to use amateur radio
if you want to go down that path.
Satellite messengers such as the Garmin Inreach or Zoleo can send SMS-like messages across anywhere in the globe with a clear view of the sky. They also often have SOS features. While these are useful safety equipment, it can take many minutes for a message to be sent and received – it’s not like an interactive SMS conversation – and there are places where local radios will have better signal. Notably, satellite messengers are almost useless indoors and can have trouble in areas without a clear view of the sky, such as dense forests, valleys, etc.
My earlier
Roundup of secure messengers with off-the-grid capabilities (distributed/mesh messengers)
highlighted a number of other options as well, for text-only communication. For instance:
For very short-range service,
Briar
can form a mesh over Bluetooth from cell phones – or over Tor, if Internet access is available.
Dedicated short message services
Mesh Network
s like
Meshtastic
or Beartooth have no voice capability, but share GPS locations and short text messages over their own local mesh. Generally they need to pair to a cell phone (even if that phone has no cell service) for most functionality.
Yggdrasil
can do something similar over ad-hoc Wifi, but it is a lower-level protocol and you’d need some sort of messaging to run atop it.
This article is primarily about the USA, though these concepts, if not the specific implementation, apply many other areas as well.
The landscape of easy personal radios
The oldest personal radio service in the US is Citizens Band (CB). Because it uses a lower frequency band than others, handheld radios are larger, heavier, and less efficient. It is mostly used in vehicles or other installations where size isn’t an issue.
The
FRS/GMRS
services mostly share a set of frequencies. The Family Radio Service is unlicensed (you don’t have to get a license to use it) and radios are plentiful and cheap. When you get a “blister pack” or little radios for maybe $50 for a pair or less, they’re probably FRS. FRS was expanded by the FCC in 2017, and now most FRS channels can run up to 2 watts of power (with channels 8-14 still limited to 0.5W). FRS radios are pretty much always handheld.
GMRS runs on mostly the same frequencies as FRS. GMRS lets you run up to 5W on some channels, up to 50W on others, and operate repeaters. GMRS also permits limited occasional digital data bursts; three manufacturers currently use this to exchange GPS data or text messages. To use GMRS, you must purchase a GMRS license; it costs $35 for a person and their immediate family and is good for 10 years. No exam is required. GMRS radios can transmit on FRS frequencies using the GMRS authorization.
The extra power of GMRS gets you extra distance. While only the best handheld GMRS radios can put out 5W of power, some mobile (car) or home radios can put out the full 50W, and use more capable exterior antennas too.
There is also the MURS band, which offers very few channels and also very few devices. It is not in wide use, probably for good reason.
Finally, some radios use some other unlicensed bands. The Motorola DTR and DLR series I will talk about operate in the 900MHz ISM band. Regulations there limit them to a maximum power of 1W, but as you will see, due to some other optimizations, their range is often quite similar to a 5W GMRS handheld.
All of these radios share something in common: your radio can either transmit, or receive, but not both simultaneously. They all have a PTT (push-to-talk) button that you push and hold while you are transmitting, and at all other times, they act as receivers.
You’ll learn that “doubling” is a thing – where 2 or more people attempt to transmit at the same time. To listeners, the result is often garbled. To the transmitters, they may not even be aware they did it – since, after all, they were transmitting. Usually it will be clear pretty quickly as people don’t get responses or responses say it was garbled. Only the digital Motorola DLR/DTR series detects and prevents this situation.
FRS and GMRS radios
As mentioned, the FRS/GMRS radios are generally the most popular, and quite inexpensive. Those that can emit 2W will have pretty decent range; 5W even better (assuming a decent antenna), though the 5W ones will require a GMRS license. For the most part, there isn’t much that differentiates one FRS radio from another, or (with a few more exceptions) one GMRS handheld from another. Do not believe the manufacturers claims of “50 mile range” or whatever; more on range below.
FRS and GMRS radios use FM. GMRS radios are permitted to use a wider bandwidth than FRS radios, but in general, FRS and GMRS users can communicate with each other from any brand of radio to any other brand of radio, assuming they are using basic voice services.
Some FRS and GMRS radios can receive the NOAA weather radio. That’s nice for wilderness use. Nicer ones can monitor it for alert tones, even when you’re tuned to a different channel. The very nicest on this – as far as I know, only the Garmin Rino series – will receive and process SAME codes to only trigger alerts for your specific location.
GMRS (but not FRS) also permits 1-second digital data bursts at periodic intervals. There are now three radio series that take advantage of this: the
Garmin Rino
, the
Motorola T800
, and
BTech GMRS-PRO
. Garmin’s radios are among the priciest of GMRS handhelds out there; the top-of-the-line Rino will set you back $650. The cheapest is $350, but does not contain a replaceable battery, which should be an instant rejection of a device like this. So, for $550, you can get the middle-of-the-road Rino. It features a sophisticated GPS system with Garmin trail maps and such, plus a 5W GMRS radio with GPS data sharing and a very limited (13-character) text messaging system. It does have a Bluetooth link to a cell phone, which can provide a link to trail maps and the like, and limited functionality for the radio. The Rino is also large and heavy (due to its large map-capable screen). Many consider it to be somewhat dated technology; for instance, other ways to have offline maps now exist (such as my Garmin Fenix 6 Pro, which has those maps on a watch!). It is bulky enough to likely be left at home in many situations.
The Motorola T800 doesn’t have much to talk about compared to the other two.
Both of those platforms are a number of years old. The newest entrant in this space, from budget radio maker Baofeng, is the BTech GMRS-PRO, which came out just a couple of weeks ago. Its screen, though lacking built-in maps, does still have a GPS digital link similar to Garmin’s, and can show you a heading and distance to other GMRS-PRO users. It too is a 5W unit, and has a ton of advanced features that are rare in GMRS: ability to pair a Bluetooth headset to it directly (though the Garmin Rino supports Bluetooth, it doesn’t support this), ability to use the phone app as a speaker/mic for the radio, longer text messages than the Garmin Rino, etc. The GMRS-PRO sold out within a few days of its announcement, and I am presently waiting for mine to arrive to review. At $140 and with a more modern radio implementation, for people that don’t need the trail maps and the like, it makes a compelling alternative to Garmin for outdoor use.
Garmin documents when GPS beacons are sent out: generally, when you begin a transmission, or when another radio asks for your position. I couldn’t find similar documentation from Motorola or BTech, but I believe FCC regulations mean that the picture would be similar with them. In other words, none of these devices is continuously, automatically, transmitting position updates. However, you can
request
a position update from another radio.
It should be noted that, while voice communication is compatible across FRS/GMRS, data communication is not. Garmin, Motorola, and BTech all have different data protocols that are incompatible with radios from other manufacturers.
FRS/GMRS radios often advertise “privacy codes.” These do nothing to protect your privacy; see more under the privacy section below.
Motorola DLR and DTR series
Although they can be used for similar purposes, and I do, these radios are unique from the others in this article in several ways:
-
Their sales and marketing is targeted at businesses rather than consumers
-
They use digital encoding of audio, rather than analog FM or AM
-
They use FHSS (Frequency-Hopping Spread Spectrum) rather than a set frequency
-
They operate on the 900MHz ISM band, rather than a 460MHz UHF band (or a lower band yet for MURS and CB)
-
The DLR series is quite small, smaller than many GMRS radios.
I don’t have space to go into a lot of radio theory in this article, but I’ll briefly expand on some of this.
First, FHSS. A FHSS radio hops from frequency to frequency many times per second, following some preset hopping algorithm that is part of the radio. Although it complicates the radio design, it has some advantages; it tends to allow more users to share a band, and if one particular frequency has a conflict with something else, it will be for a brief fraction of a second and may not even be noticeable.
Digital encoding generally increases the quality of the audio, and keeps the quality high even in degraded signal conditions where analog radios would experience static or a quieter voice. However, you also lose that sort of audible feedback that your signal is getting weak. When you get too far away, the digital signal “drops off a cliff”. Often, either you have a crystal-clear signal or you have no signal at all.
Motorola’s radios leverage these features to build a unique radio. Not only can you talk to a group, but you can select a particular person to talk to with a private conversation, and so forth. DTR radios can send text messages to each other (but only preset canned ones, not arbitrary ones). “Channels” are more like configurations; they can include various arbitrary groupings of radios. Deconfliction with other users is established via “hopsets” rather than frequencies; that is, the algorithm that it uses to hop from frequency to frequency. There is a 4-digit PIN in the DLR radios, and newer DTR radios, that makes privacy very easy to set up and maintain.
As far as I am aware, no scanner can monitor DLR/DTR signals. Though they technically aren’t encrypted, cracking a DLR/DTR conversation would require cracking Motorola’s firmware, and the chances of this happening in your geographical proximity seem vanishingly small.
I will write more below on comparing the range of these to GMRS radios, but in a nutshell, it compares well, despite the fact that the 900MHz band restrictions allow Motorola only 1W of power output with these radios.
There are three current lines of Motorola DLR/DTR radios:
-
The Motorola DLR1020 and DLR1060 radios. These have no screen; the 1020 has two “channels” (configurations) while the 1060 supports 6. They are small and compact and great pocketable “just work” radios.
-
The Motorola DTR600 and DTR700 radios. These are larger, with a larger antenna (that should theoretically provide greater range) and have a small color screen. They support more channels and more features (eg, short messages, etc).
-
The
Motorola Curve
(aka DLR110). Compared to the DLR1060, it adds limited WiFi capabilities that are primarily useful in certain business environments. See
this thread
for more. These features are unlikely to be useful in the environments we’re talking about here.
These radios are fairly expensive new, but DLRs can be readily found at around $60 on eBay. (DTRs for about $250) They are quite rugged. Be aware when purchasing that some radios sold on eBay may not include a correct battery and charger. (Not necessarily a problem; Motorola batteries are easy to find online, and as with any used battery, the life of a used one may not be great.) For more advanced configuration, the
Motorola CPS cable
works with both radios (plugs into the charging cradle) and is used with the
programming software
to configure them in more detail.
The older Motorola DTR650, DTR550, and older radios are compatible with the newer DLR and DTR series, if you program the newer ones carefully. The older ones don’t support PINs and have a less friendly way of providing privacy, but they do work also. However, for most, I think the newer ones will be friendlier; but if you find a deal on the older ones, hey, why not?
This thread on the MyGMRS forums
has tons of useful information on the DLR/DTR radios. Check it out for a lot more detail.
One interesting feature of these radios is that they are aware if there are conflicting users on the channel, and even if anybody is hearing your transmission. If your transmission is not being heard by at least one radio, you will get an audible (and visual, on the DTR) indication that your transmission failed.
One thing that pleasantly surprised me is just how tiny the Motorola DLR is. The whole thing with antenna is like a small candy bar, and thinner. My phone is slightly taller, much wider, and only a little thinner than the Motorola DLR. Seriously, it’s more pocketable than most smartphones. The DTR is of a size more commonly associated with radios, though still on the smaller side. Some of the most low-power FRS radios might get down to that size, but to get equivolent range, you need a 5W GMRS unit, which will be much bulkier.
Power
These radios tend to be powered by:
-
NiMH rechargable battery packs
-
AA/AAA batteries
-
Lithium Ion batteries
Most of the cheap FRS/GMRS radios have a NiMH rechargable battery pack and a terrible charge controller that will tend to overcharge, and thus prematurely destroy, the NiMH packs. This has long ago happened in my GMRS radios, and now I use Eneloop NiMH AAs in them (charged separately by a proper charger).
The BTech, Garmin, and Motorola DLR/DTR radios all use Li-Ion batteries. These have the advantage of being more efficient batteries, though you can’t necessarily just swap in AAs in a pinch. Pay attention to your charging options; if you are backpacking, for instance, you may want something that can charge from solar-powered USB or battery banks. The Motorola DLR/DTR radios need to sit in a charging cradle, but the cradle is powered by a Micro USB cable. The BTech GMRS-PRO is charged via USB-C. I don’t know about the Garmin Rino or others.
Garmin offers an optional AA battery pack for the Rino. BTech doesn’t (yet) for the GMRS-PRO, but they do for some other models, and have stated accessories for the GMRS-PRO are coming. I don’t have information about the T800. This is not an option for the DLR/DTR.
Meshtastic
I’ll briefly mention
Meshtastic
. It uses a low-power
LoRa
system. It can’t handle voice transmissions; only data. On its own, it can transmit and receive automatic GPS updates from other Meshtastic devices, which you can view on its small screen. It forms a mesh, so each node can relay messages for others. It is also the only unit in this roundup that uses true encryption, and its battery lasts about a week – more than the “a solid day” you can expect out of the best of the others here.
When paired with a cell phone, Meshtastic can also send and receive short text messages.
Meshtastic uses much less power than even the cheapest of the FRS radios discussed here. It can still achieve respectable range because it uses LoRa, which can trade bandwidth for power or range. It can take it a second or two to transmit a 50-character text message. Still, the GMRS or Motorola radios discussed here will have more than double the point-to-point range of a Meshtastic device. And, if you intend to take advantage of the text messaging features, keep in mind that you must now take two electronic devices with you and maintain a charge for them both.
Privacy
The privacy picture on these is interesting.
Cell phone privacy
Cell phones are difficult for individuals to eavesdrop, but a sophisticated adversary probably could: or an unsophisticated adversary with any manner of malware. Privacy on modern smartphones is a huge area of trouble, and it is safe to say that data brokers and many apps probably know at least your location and contact list, if not also the content of your messages. Though apps such as Signal can certainly help. See
Tools for Communicating Offline and in Difficult Circumstances
for more details.
GMRS privacy
GMRS radios are unencrypted and public. Anyone in range with another GMRS radio, or a scanner, can listen to your conversations – even if you have a privacy code set. The privacy code does not actually protect your privacy; rather, it keeps your radio from playing conversations from others using the same channel, for your convenience.
However, note the “in range” limitation. An eavesdropper would generally need to be within a few miles of you.
Motorola DLR/DTR privacy
As touched on above, while these also aren’t encrypted, as far as I am aware, no tools exist to eavesdrop on DLR/DTR conversations. Change the PIN away from the default 0000, ideally to something that doesn’t end in 0 (to pick a different hopset) and you have pretty decent privacy right there.
Meshtastic
Meshtastic uses strong encryption. But as messaging features require a paired phone, the privacy implications of a phone also apply here.
Range
I tested my best 5W GMRS radios, as well as a Motorola DTR600 talking to a DLR1060. I took a radio with me in the car, and had another sitting on my table indoors. Those of you familiar with radios will probably recognize that being in a car and being indoors both attenuate (reduce the strength of) the signal significantly. I drove around in a part of Kansas with gentle rolling hills.
Both the GMRS and the DLR/DTR had a range of about 2-2.5 miles. There were times when each was able to pull out a signal when the other was not. The DLR/DTR series was significantly better while the vehicle was in motion. In weaker signal conditions, the GMRS radios were susceptible to significant “picket fencing” (static caused by variation in the signal strength when passing things like trees), to the point of being inaudible or losing the signal entirely. The DLR/DTR remained perfectly clear there. I was able to find some spots where, while parked, the GMRS radios had a weak but audible signal but the DLR/DTR had none. However, in all those cases, the distance to GMRS dropping out as well was small. Basically, no radios penetrate the ground, and the valleys were a problem for them all.
Differences may play out in other ways in other environments as well: for instance, dense urban environments, heavy woods, indoor buildings, etc.
GMRS radios can be used with repeaters, or have a rooftop antenna mounted on a car, both of which could significantly extend range – and both of which are rare.
The DLR/DTR series are said to be exceptionally good at indoor environments; Motorola rates them for penetrating 20 floors, for instance. Reports on MyGMRS forums state that they are able to cover an entire cruise ship, while the metal and concrete in them poses a big problem for GMRS radios. Different outdoor landscapes may favor one or the other also.
Some of the cheapest FRS radios max out at about 0.5W or even less. This is probably only a little better than yelling distance in many cases. A lot of manufacturers obscure transmit power and use outlandish claims of range instead; don’t believe those. Find the power output. A 2W FRS transmitter will be more credible range-wise, and the 5W GMRS transmitter as I tested better yet. Note that even GMRS radios are
restricted
to 0.5W on channels 8-14.
The Motorola DLR/DTR radio gets about the same range with 1W as a GMRS radio does with 5W. The lower power output allows the DLR to be much smaller and lighter than a 5W GMRS radio for similar performance.
Overall conclusions
Of course, what you use may depend on your needs. I’d generally say:
-
For basic use, the high quality, good range, reasonable used price, and very small size of the Motorola DLR would make it a good all-arounder. Give one to each person (or kid) for use at the mall or amusement park, take them with you to concerts and festivals, etc.
-
Between vehicles, the Motorola DLR/DTR have a clear range advantage over the GMRS radios for vehicles in motion, though the GPS features of the more advanced GMRS radios may be more useful here.
-
For wilderness hiking and the like, GMRS radios that have GPS, maps, and NOAA weather radio reception may prove compelling and worth the extra bulk. More flexible power options may also be useful.
-
Low-end FRS radios can be found very cheap; around $20-$30 new for the lowest end, though their low power output and questionable charging circuits may limit their utility where it really counts.
-
If you just can’t move away from cell phones, try the Zoleo app, which can provide some radio-like features.
-
A satellite communicator is still good backup safety gear for the wilderness.
Postscript: A final plug for amateur radio
My 10-year-old Kenwood TH-D71A already had features none of these others have. For instance, its support for
APRS
and ability to act as a digipeater for APRS means that TH-D71As can form an automatic mesh between them, each one repeating new GPS positions or text messages to the others. Traditional APRS doesn’t perform well in weak signal situations; however, more modern digital systems like D-Star and DMR also support APRS over more modern codecs and provide all sorts of other advantages as well (though not FHSS).
My conclusions above assume a person is not going to go the amateur radio route for whatever reason. If you can get those in your group to get their license – the technician is all you need – a whole world of excellent options opens to you.
Note:
This article has a
long-term home
on my website, where it may be updated from time to time.
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