WARNING
Never remove the antenna without first ensuring that transmit (TX) is disabled in settings. These radios automatically transmit periodic updates to the mesh, and damage will occur if the radio happens to transmit while the antenna is removed. This applies even to quick antenna swaps. The TL;DR is to NEVER under any circumstances remove the antenna without first ensuring that TX is disabled in settings: Settings > Radio Configuration > LoRa > Transmit Enabled (toggle off)
A note about this guide: Please be mindful that Meshtastic (and Meshcore) is an open source project in beta, and therefore it’s constantly changing and evolving as the developers make updates to the protocol, as well as to the various clients and apps. That being the case, it’s likely that some of the information in this guide may be outdated. If you’re having trouble locating a setting, it’s likely that the name or location has changed, so you may have to apply some common sense critical thinking. If in doubt, the best source for the latest information for any given application is the official Meshtastic Discourd: www.discord.com/invite/meshtastic
QUICK SETUP
Install antenna: If it’s not already installed, screw the antenna onto the SMA connector on the top of the radio finger tight, being careful not to overtighten.
Plug in radio: Radio may be in deep sleep or depleted, so plug it into an external power source to wake it up. Remove silicone plug on radio’s base and power via USB-C cable (not included).
Pair radio with smart device: Install Meshtastic app on smart device (make sure Bluetooth is enabled on smart device and enable all app permissions). Meshtastic is available for both Android and iOS. Go to Connect tab in Meshtastic app and connect radio (PIN is 123456).
Set your LoRa region: Before the radio will function, you have to set your region so it knows what frequency to use. Settings > Radio Configuration > LoRa. The app may prompt you to do this once the Bluetooth connection is established.
Change Bluetooth PIN (optional): Change factory default PIN by going to Settings > Device Configuration > Bluetooth > Fixed Pin, enter your own PIN, then hit Save. Note that you will have to “forget” the radio in your smart device’s Bluetooth settings to clear the factory default PIN, then reconnect the radio in the app with the PIN you just set. This can be done later if you want to skip for now.
Change Position setting for Primary channel (optional): The default setting is to broadcast your approximate location to the public mesh. To disable, go to Settings > Channels > Primary Channel > Position. Toggle off and hit Save (radio will restart). Note that this will not affect position sharing on encrypted channels (more on that later). This can be done later if you want to skip for now.
Turn on transmit: Radios are shipped with transmit disabled for safety, so you must re-enable it in app before you can send messages. In app, go to Settings > Radio Configuration > LoRa > Transmit Enabled. Toggle on and hit save (radio will restart). NEVER remove antenna without re-disabling TX!
Send a message: Send a message (e.g. “Radio check”) on the Primary channel by going to Messages > Channels > Primary Channel. If there are other users within range, you should see “Acknowledged” appear under the message (indicating another node has received it), and you may get replies. You should also see nearby nodes start to populate in the Nodes tab (and on the Map) within a few hours if there is any significant public mesh in your area. If you don’t see any activity, it’s probably because there aren’t any active users within range, so you will need to set up a second radio before you can do a successful test.
ADVANCED SETUP
Set custom name: You can rename your node by going to Settings > Device Configuration > User and changing the Long and or Short names. Note that Short Name is what appears on the node icon as seen by other users and may be an emoji. Keep in mind that both names are broadcast to the public mesh, so don’t use personally identifiable information. Note that it’s helpful to write the node’s short name on the housing.
Set up private channel: Never encrypt the Primary channel, as you will break your connection to the public mesh. Don’t change any primary channel settings (other than the Position, as mentioned in the previous section). Encrypt one of the other channel slots and set it to Secondary (Settings > Channels > Add Channel). The channel name is like a user name, and the encryption key is like a password. Anyone else with those credentials can send and receive encrypted messages over that channel. Set Position to precise, as only the people you give those credentials to will be able to see your location.
Specify Role: The radios come set to Client, which is the default standard role for mesh nodes. If you intend to use ATAK (or iTAK), change that to TAK (Settings > Device Role > TAK). Otherwise, Client is probably what you want. DO NOT set any Router/Repeater roles unless you’re 100% sure it’s appropriate, as you may break your local mesh.
Choose LoRa Preset: There are several presets that balance range with data rate (Settings > Radio Configuration > LoRa > Presets). Long-Fast is the default, so it serves as kind of like a “national calling frequency” equivalent for Meshtastic. I.e. if you’re lost in the wilderness and need to send an SOS, Long-Fast is likely the preset that’s going to get you found. Medium-Fast can handle more traffic so it’s more common in cities, and Long-Slow extends range at the expense of traffic handling, so it’s often used by rural users, especially if there’s no public mesh in their area yet. Message boards and social media groups for local meshes are the best place to find out which preset is most prevalent in your area. If all else fails, just try them out to see what’s out there, starting with Long-Fast. Send a message (e.g. “Radio check”) on the Primary channel from different locations and see who responds or what nodes populate in the Node List and on the Map.
TROUBLESHOOTING
Resetting the node will immediately solve most issues (see next section NOTES ON RESET BUTTON).
Bluetooth pairing issues not fixed by resetting the node are most often fixed by forgetting the node in your phone’s Bluetooth settings and then reconnecting the radio in the app.
If the device is paired but issues persist, try rebooting the device via the app by selecting the device in the “Nodes” tab and tapping “Reboot.” If issues still persist, factory resetting and reflashing the firmware will help rule out any non-hardware related issues.
NOTES ON RESET BUTTON
The reset pin is wired to either a screw or copper contact (depending on model) behind the antenna. You can reset the device by shorting it to the antenna connector’s hex nut (simply using a metal object like a paper clip to connect the two together). If the device is painted, you will need to scratch away a little bit of the paint to expose bare metal. A very brief “tap” is all it takes (if you hold it too long the node will see that as a double tap and put it into DFU mode, so if the node doesn’t respond try a faster tap). This is primarily to recover the node if it malfunctions in the field. For normal operation like updating firmware, it’s easiest to control it via the app or web client. Naturally there exists the remote possibility of something metallic in your pocket or bag shorting them unintentionally, so painting them or putting some electrical tape around any exposed portion of antenna connector will preclude that remote possibility.
NOTES ON ANTENNAS
The antenna market for Meshtastic is the wild west. We highly recommend the TEC ANT-916-CW-HW-SMA for handhelds (mobile and base applications require specific consideration). If you choose to use a different antenna (you do so at your own risk), please use extreme caution, as there are lots of antennas on the market that are not only subpar but will even damage radios. If you do decide to experiment with other antennas, NEVER use any antenna that’s not expressly designed for the ISM 915mhz band (keeping in mind that many antennas marketed as such are out of band), or that doesn’t have a real SMA connector. We leave as much of the radio side SMA protruding as possible so as not to preclude the use of a counterpoise by advanced users, so fake SMA connectors that rely on the antenna body’s shoulder for proper indexing of the center pin will damage the radio’s SMA connector and potentially destroy the radio itself. Even if you shim such fake antennas, the impedance will be unpredictable, potentially leading to a high enough SWR to damage the radio in a perfect storm scenario. SMA connectors rely on EXTREMELY precise indexing of the center pin, and a good connection between the two shells for proper ground, which yields a repeatable 50 ohm connection. The male SMA shell nests inside the female shell, and there is also a tapered shoulder that provides the proper airgap between the two PTFE dielectrics surrounding each connector’s center pin. Close enough simply isn’t good enough when it comes to antenna connectors.
NEVER use SMA to N-Type adapters, as the strain of those antennas is too great for SMA connectors and will likely lead to damage. SMA connectors are quite delicate and easily damaged, so try to opt for shorter more flexible antennas like whips and ducks vs rigid ones with hard plastic shells. High gain antennas are also not ideal for handheld radios because they require good placement to be effective, as they concentrate the signal in a much smaller area, thus requiring much more intentional placement. For radios carried on your person, you want a lower gain whip antenna with a broad radiation pattern (omnidirectional with maximum gains in the range of 0-3db).
Also be cautious with adapters with coax extensions. While this will relieve the strain on the radio’s connector, the coax and additional connections will eat up your signal, and when you’re talking about Meshtastic’s 20db output it doesn’t take much to reduce your signal to the extent that any range you may have otherwise gained with a larger antenna will be canceled out by weakening your signal. If using such a setup, make sure you’re using very high quality connectors and coax cable, and keep coax runs to several feet max.
Also keep in mind that these radios have very small ground planes, so try to only use antennas that have a built-in counterpoise (like the aforementioned TEC). Most antennas require about a 100mm square ground plane to get the advertised performance, and many that are designed for vehicle applications require several square feet of ground plane. Unless you’re highly skilled when it comes to improvising ground planes, it’s best to stick with antennas that have a built in counterpoise.
Most importantly, NEVER swap antennas without first disabling Transmit (TX) in the settings (Settings > Radio Configuration > LoRa > Transmit Enabled (toggle off)).
NOTES ON SECURITY
It’s no secret that Meshtastic is most popular in the US with the 2A community, so to a savvy criminal anything that affiliates you with Meshtastic could be much akin to the same security concerns with, for example, having an NRA sticker on your vehicle.
Bad actors can spoof nodes on the primary channel (broadcast someone else’s node information), but you can preclude that possibility by “favoriting” known nodes (if two nodes have the same name, the “favorited” one is the real one). Even then, treat everything on the primary channel as suspect.
Broadcasting your approximate location on the Primary channel is helpful to the public mesh, as it assists others in testing nodes, but it could be a security concern (in general, not just in an operational scenario). While it’s less likely that the approximate location of a fixed node could be exploited, a moving node presents more potential for exploitation by criminals, as that data could be used to track you (e.g. learn your habits, see when you’re not home, etc.). For that reason, I like to set fixed nodes (e.g. base stations) to within 90 meters or so, but turn position reporting off completely on the Primary channel for HT or mobile nodes. The density determines how safely you can report your position (e.g. if you’re the only house for five miles, any meaningful position report would give away your precise location).
If a radio containing your private channel’s encryption key is lost or stolen, you must consider that channel and key to be compromised and set up a new one. The key can also be compromised if someone hacks your smart device, so securing your smart device is just as important. Best practice is to rotate keys on a regular schedule.
Even encrypted messages can be intercepted and triangulated, so always be mindful that while your encrypted messages can’t be deciphered, any radio transmission essentially broadcasts your position to anyone within range of your signal. Listening is free, however, so if that’s a concern you can always disable TX and only enable it to transmit from random locations when necessary.
NOTES ON CONFIGURING MQTT
MQTT allows you to send Meshtastic messages over the internet using your phone’s Wi-Fi or 5G connection. The nRF52s aren’t capable of handling large amounts of traffic, so if enabling MQTT causes the device to behave erratically or stop working altogether, join a less busy Root Topic (or create your own Root Topic (e.g. “my_root_topic”). Practically speaking, these devices can only handle small amounts of MQTT traffic, so the reasonable use case is to only use MQTT to pass messages for your own inner circle, vs. joining a regional group (set unique Root Topic for your group and only enable MQTT on your private encrypted channel).
NOTES ON DUST, WATER, AND DROP
The entire assembly is fully potted in silicone encapsulant, which is degassed at 30” Hg, so it’s inherently very dust and water resistant, and it’s unlikely that water is going to be able to penetrate into the electronics in any normal conditions. What’s vulnerable is the USB-C port, but a simple cover keeps it impervious to dust and highly resistant to water. The alternative would have been an Amphenal milspec USB-C receptacle, which, besides being very costly, would have dramatically increased the footprint, and with a little common sense the standard USB-C receptacle shouldn’t present any limitations.
While water in the USB-C port isn’t immediately harmful, and, most importantly, water shouldn’t be able to migrate from the port into the main board, at least not without significant pressure, repeated or prolonged exposure will corrode the contacts. Silicone USB-C plugs are very effective for splash and even some submersion scenarios, so keep those and use them. Electronics rated protectant oils are also good if it’s going to be used in wet and or salty conditions, in conjunction with preventing moisture and drying it out quickly if moisture does penetrate (like if you were forced to charge it while moving in a driving rain).
Also note that SMA connectors aren’t waterproof. Use dielectric grease to waterproof them, which will maintain electrical continuity between the connectors.
The silicone encapsulant also provides a lot of drop protection to the electronics themselves. If the device is dropped and the housing is damaged, it’s nearly certain that the electronics inside will be fine (within reason), and the silicone is soft enough that the electronics can be reinstalled in a new housing if necessary. The housing being plastic is actually mostly beneficial to the electronics inside, as any drop severe enough to break the housing could be severe enough to damage electronics via shock, so the ductility of the housing provides some shock protection in addition to the silicone potting. ASA (similar to ABS, popular for automotive applications) is also stable at normal temperatures on earth, so basically any temperature that won’t kill you won’t kill it either. So, while you still shouldn’t leave it in a car in the summer (for the battery’s sake, mostly), you don’t have to worry about it melting like typical 3D printed things do.
The TL;DR is that while this device is undoubtedly EXCELLENT for its size, weight, and cost in the durability department, please observe the “if you take care of it, it will take of you” approach.
In the event you’re concerned about EMP, the TL;DR is that nobody, not even the experts, really knows, so keep it in a faraday can if that’s in your wheelhouse. HOWEVER, these devices would ALMOST undoubtedly be just fine in most cases, as the conductive elements are teeny tiny and the antennas are relatively short, so it would for sure take an immense amount of energy to induce enough current to damage them. HT radios are generally thought to be low risk for EMP damage, and these are especially low risk due to the very small antennas. Storage with the antenna removed would almost certainly ensure survival (just be sure to disable transmit in the settings before removing the antenna, as always).
NOTES ON BATTERY LIFE AND CHARGING
We put gigantic batteries in these radios, which operate at a mere ~10mA (yes, milliamps), so don’t be alarmed when they don’t go from 0% to 100% percent charge in a few hours. A full charge from empty will take about three days (or more with 21700s). This is like having a laptop battery the size of a suitcase; it will last practically forever, but it will also take longer to charge to full.
That said, a charge of a few hours, even from a low current source (like a small solar panel), will provide up to several days of use, so don’t worry just because the app says it’s low (it only sees voltage, not actual capacity). Anything over 3v means you have a day or more of normal use. Anything over 4v means you have at least a week of normal use.
The charging circuitry maxes out at 100mA, so even a small solar panel can provide more than enough current to charge them. Or if you’re using a single portable solar solution for all of your devices, these won’t slow down your higher draw devices by any perceptible amount (i.e. charge them from the same panel as your phone, and you won’t notice your phone charging any slower than usual).
Settings impact battery life a lot, as does traffic volume. In standby, the current draw is mere microamps, so with optimized settings these radios can last for over two weeks on a single charge. In a very heavy use scenario, such as a repeater for a busy mesh, that could get cut down to just a few days, so be mindful of the fact that these are handheld transceivers designed for use by a single operator in client mode. While they could be repurposed as routers in a pinch, they weren’t designed to handle heavy traffic.
It’s ideal to not charge past 4v or let the battery fall below about 3.5v during normal use (about 50% and 80% respectively). This will increase battery longevity from around 500 charge cycles to about 2,000 charge cycles. Smart chargers can be used to automatically stop charging at a specified voltage. Not to worry, though, if you do need the full charge, the radio’s charge/discharge curent is so low that it’s already very gentle for such a large battery.
Temperature also has a very heavy impact on battery health, so avoid extreme temperatures, especially hot cars. It is possible that a car in a hot climate can reach a temperature hot enough to cause immediate damage to a lithium battery, and repeated exposure to high temperature can dramatically reduce battery health over time, as the electrolyte inside the cell becomes very corrosive to the lithium at high temperatures.
There is no battery cutoff switch, meaning the device can never be fully turned off. Waterproof switches are bulky and expensive, and with a little common sense these nodes don’t require them due to their extremely low power consumption in deep sleep mode. The main thing is not to let the battery self discharge below the threshold required to start the battery protection circuit (at which point the device will become unrecoverable). In other words, don’t just toss it in a drawer and leave it for months on end. Make sure you’re charging the device once a month or so. In reality, it will probably take multiple months in most cases for the battery to fall below critical levels after the protection circuit has cut power to the main board. However, these nodes are designed to be constant companions. Even if you’re not actively using the features, they’re constantly exploring and mapping the mesh around you, and discovering new nodes and clearing stale ones. Activity on the primary channel also keeps you informed about local mesh news, like the installation of new routers. Getting the most out of Meshtastic means staying up to date one what’s where, so you will be able to always position yourself to get reception. Like any radio service, half the battle is just knowing where everyone else is, where the dead spots are, and how the terrain and RF around you affects your coverage. If you have accidentally let your battery discharge below critical levels (i.e. it won’t charge), you can first try warming it up while it’s plugged in, such as leaving it in a warm car or in a room with a space heater for several hours, which might put the voltage over the threshold to start charging again. If that doesn’t do the trick, you will have to send it in for battery replacement. If you do need to store it for some time unused, charge it to full, put all settings on power saving, disable transmit, and remove the antenna; these steps will give it the longest “shelf life” possible.
RESOURCES
www.discord.com/invite/meshtastic
www.facebook.com/themeshtastic
Don’t hesitate to contact us if you have any questions!