There is a point beyond the last cell tower where the phone goes to zero bars. The hiker can no longer see the trail app; the rancher has lost touch with the truck on the other side of three ridgelines.
That is when off-grid technology is called for. In place of a carrier network these devices put you on radio and solar power with a small computer to make sure your data and messages keep moving.
This guide shows you how mesh radios do their job routing a message and what the difference is between Meshtastic and MeshCore. It gets into the handhelds that can stand up to field conditions, as well as solar repeaters, GPS trackers, and phones made for dead zones.
What Off-Grid Technology and Devices Actually Do
The Radio Chip That Makes It Possible
What you have with off-grid technology is a system that does away with cell towers in favour of short radio hops. The work is done by a LoRa module, a modest chip that relays a signal from one piece of equipment to another. In this way the message is passed along until it gets where it is meant to be. There is no need for an internet backbone or a SIM card, and certainly no monthly bill to contend with.
Why Coverage Grows with Every Device
Mesh networking is the term for an approach that will scale as one puts more devices in place. The logic is straightforward: with a greater number of radios out in the field, you get better coverage and delivery to be relied on. Put a node on a ridge and a dead spot is no longer without signal.
Ready-Built Beats DIY
Then there are firms such as SpecFive that have put together hardware to do just that. They offer off-the-shelf kits with rugged cases, GPS chips and LoRa radios all in one. One could go with raw parts, but those need to be soldered, flashed and tested to ensure they are dependable. A completed device from them obviates the need for any of that. It comes to you charged and pre-configured, so it can be part of the mesh as soon as it is turned on.
A Category Bigger Than Walkie-Talkies
We have moved well past the days when this category was limited to a basic two-way radio. Today it encompasses solar relays, GPS tracking and even a complete Linux handheld with an integrated radio.
For the buyer, the process typically begins with one question in mind: what is the required range for the message and how many recipients are there? The answer to that will be the determining factor for nearly everything else covered in this guide.
Meshtastic vs MeshCore: Picking the Right Protocol
When it comes to firmware, there are two that hold sway in this area at present. One is bound to encounter the meshcore vs meshtastic debate. They share the same LoRa hardware and can be relied on to put out encrypted text and GPS data even where there is no cell service. The distinction between them is how they go about routing traffic, and in that regard, they could not be more different.
How Meshtastic Handles Messages
With Meshtastic, one finds a flooding approach in play. Any device that picks up a message will put it out to its neighbors. There is no need for prior planning, so getting things set up is almost immediate. The trade-off is that as the network grows, so does the volume of repeated traffic.
How MeshCore Handles Messages
MeshCore takes a different tack by giving devices fixed roles. You have dedicated repeaters to handle long-haul traffic while companion units are content to communicate with those in their vicinity or other repeaters. Such an arrangement keeps down the chatter and is well suited to large deployments where some forethought has been put in.
Which Protocol Fits Your Situation
There is no clear victor between the two protocols. You will find Meshtastic to be the better fit for casual, unscripted use, whereas MeshCore is what one would want for a more formal network with repeaters in fixed positions.
With SpecFive’s Relay and Spectre Pro, firmware for both are available from the factory, meaning there is no need to be tied to a single option. Should you wish to get on a network today, go with Meshtastic; it can have you up and running in less than twenty minutes. On the other hand, for establishing permanent infrastructure at an event or out on a ranch, the role-based approach of MeshCore will see to it that traffic remains orderly as the number of nodes increases. But do not think your choice of firmware makes a difference if the antenna is in the wrong spot; range will be limited regardless.
Handheld Linux Computers Built for the Field
The Strike: A Pocket-Sized Workstation
There is more to a Linux handheld than just the ability to put out a message. Take the SpecFive Strike, for instance: this portable Linux computer has a LoRa radio on board and can double as a terminal for system administration or coding by virtue of its full QWERTY keyboard and 4.3-inch touchscreen. Under the hood is a Raspberry Pi Compute Module, which means it will run Raspberry Pi OS as well as any custom Linux builds one might want to put on it.
The Nomad 2: When You Need More Power
The Specfive Nomad 2, with its raspberry pi at the core, is better suited to the demands of heavier field work. Built on the same Linux platform it puts in a spectrum receiver, GPS and a hot-swappable battery tray. In doing so it becomes a true pocket linux computer for keeping an eye on radio activity without losing your mesh connection. With these two devices there is no longer any need to make separate acquisitions for a handheld linux computer and a mesh radio.
Weight, Battery, and the Keyboard That Matters
At less than 400 grams the Strike is light enough to handle, with an internal battery that will see one through three to six hours of work. The Nomad 2 is a bit different; it forgoes some of that portability in favour of a hot-swappable tray for the battery, meaning a member of the team can have spares on hand and there is no question of lost uptime. Then there is the matter of the linux handheld with its keyboard layout found on both models.
Meshtastic Devices for Sale: Radios, Phones, and More
A look at what is on the market for meshtastic devices reveals an assortment of form factors, be it a smartphone type or a more compact radio. In the end, the choice comes down to how much one is prepared to carry.
Trekker and Ranger Radios
For hikers and small teams, the likes of the Trekker and Ranger line are the most popular meshtastic lora options. These clip-on radios do not add any superfluous weight and yet cover the essentials; with a Bluetooth link to your phone app, you have GPS sharing and messaging at hand.
Spectre Pro: A LoRa Meshtastic Phone
The Spectre Pro is as close to a smartphone as you will find in a meshtastic phone. An Android device with a camera, it can run on both LoRa mesh and LTE. In a way the hybrid design makes it a lora cell phone as well; put in a prepaid SIM and there is instant cellular data available. You will not have to make a choice between network types like with other mesh phones on the market, which is what gives this dual-mode model its edge. And since it comes with Meshtastic apps already on it, one can be sending messages within minutes of opening the box.
Matching a Device to Your Use Case
There is no one size fits all when it comes to buyers. A lone hiker will likely opt for the compact Trekker to save on weight, while a family or small group might find the Spectre Pro more to their liking; its Android foundation means they can put everyday apps to use as soon as LTE is back in range. Then you have larger outfits like ranchers and first responders who are not content with just a phone. They will combine radios and relays, as a purpose-built meshtastic unit is less of a drain on power during a long shift. For those in agriculture, healthcare or emergency response, SpecFive has done the legwork of assembling a functional kit from the ground up by offering pre-made bundles tailored to the job at hand.
Extending Range with Relays and Solar Repeaters
The Relay: A Solar-Powered Repeater
There is a limit to what one can do with just a handheld unit. The meshtastic relay gets around that; placed in an elevated and stationary position, it will forward traffic for all in the vicinity. Take the Relay from SpecFive, for instance. It is a solar repeater of the meshtastic variety, equipped with a 12-watt panel and a pair of rechargeable batteries to keep itself powered. In this way it can operate on its own, day in and day out, with no need to be plugged into the wall.
Range, ATAK, and the MeshCon Community
Ranches, remote base camps and disaster response teams all put this type of mesh radio infrastructure to good use. One Relay is enough to put down a few miles of coverage; in an urban environment that might be one to three miles, but over open country it can be five to ten or more, the terrain and antenna height being the deciding factors.
Then there are the SpecFive meshtastic devices. Some come with ATAK meshtastic firmware to integrate with ATAK and give teams who are already on tactical mapping software a common picture of the situation. On a social level, SpecFive has its own gathering for the mesh networking set every year at MeshCon. In the end, they are long range communication tools designed for unattended work over extended periods.
Car Nodes and the Beacon
There is more to network extension than just fixed radios. Several owners will put a spare unit in the cab of a work truck or other vehicle, making for a meshtastic car node that is mobile and can take the mesh with it on a patrol. And for a camp or property line where power is not to hand, but constant coverage is called for, a solar Beacon serves well as a stationary base station.
Off-Grid GPS Tracking Without Cell Service
Trace and Trace XR
When cell service is not to be had, keeping tabs on personnel, equipment or pets becomes a challenge. LoRa trackers are the answer in such circumstances; they do away with the need for a mobile signal where one would otherwise have to rely on a satellite GPS unit. But these are not like satellite gear. They tap into the very same mesh network as your radios and put out location data via the nodes in the vicinity at thirty second intervals. Take the Trace and Trace XR from SpecFive for instance.
These can be attached to a backpack strap, vest or collar and will give you hours of use from their rechargeable battery without any subscription costs.
Accuracy and Pairing with a Relay
For shorter-range applications, say for monitoring a working dog or a small party on the trail, the standard Trace is the right fit. Then there is the Trace XR, with its external antenna upgrade to put more distance between the unit and the user; it is built for the demands of tactical teams and search parties in larger zones. In terms of accuracy, either will give you a location fix to within twenty or forty feet, allowing one to zero in on a last known spot without delay. Since the trackers make use of mesh nodes in the vicinity as opposed to satellites, having a Relay or Beacon at hand will do much to enhance coverage over open ground.
Getting Started with Your First Setup
Test Two Radios First
One need not have a deep technical background or a big budget to put together a functional mesh network. The process is straightforward.
- Begin with a pair of radios; there is no point in having just one, as it would have nothing to communicate with.
- Use Bluetooth to link them up with the respective companion apps and put in a test message from close by.
- After that, take one of the units some distance off and see if the connection remains solid. It is a good way to get a read on your actual range before you must count on it out in the field.
Add a Relay, Then a Tracker
Should the property or route be of a size that demands it, put in a solar relay. Make sure to mount it as high up as you can; nothing will do more for your line-of-sight range than the extra elevation. As for the GPS tracker, leave that for last. It is best to have the mesh backbone proven and solid before you are relying on it to put your finger on a person or pet, so install it after the core radios are up and running.
Then there is the matter of the ridge where we began. A little signal loss need not put an end to the outing. Whether it is a radio in one’s pocket, a tracker on a collar or a relay fixed to a fence post, they all come down to the same thing: one does not need a tower to be reachable. These days off-grid devices handle almost everything that was once the province of cell service. You can begin with a phone or radio and as the need for range presents itself, bring in a solar relay and some GPS tracking for any gear or people you would rather not lose.
SpecFive's full lineup, including the Strike, Spectre Pro, Relay, and Trace, is available at specfive.com, built and configured in Texas so it works the moment it arrives.
