Meshtastic CONOP

The baseline Meshtastic hardware kit consists of the following in one of two configurations. The "Pocket" configuration is equipped with a pager-style case and a 2000mAh battery. The "Slim Pro" case has a 3000 mAh battery. The baseline kit costs roughly $55 to produce, though this requires purchasing sets of some of the parts.

• An assembled Heltec V3 with SMA-F connector:
  • A Heltec V3 radio, or this version with 3000 mAh battery
  • A battery, depending on the case. For the Pocket case, this 2000 mAh battery fits. For the Slim Pro case, the MakerFocus or MakerNova 3000 mAh battery should be used.
  • A stubby antenna kit, which includes the U.FL to SMA Female connector cable for the Pocket case; for the Slim Pro, a right-angle SMA connector is needed. This antenna is suited for outdoor use in closer proximity or low-profile radio usage; for urban work or longer range, an antenna such as this soft whip antenna should be used. Note that the antennas suitable for the Slim Pro case are limited to narrow-base antennas due to the cutout on the case.
  • The appropriate case with mounting options:
    • The Pocket case, which offers a MOLLE and Baofeng-clip mount. The Baofeng clip mount requires the use of heat-set inserts, which uses additional manufacturing capabilities that might not be available.
    • The Slim Pro case (the Slim 3K) offers a desk stand, Baofeng clip that uses nuts or heat-set inserts, and a MOLLE clip.
• A project box to store it in, which requires 6x M3x30mm screws to assemble. The current project box is the 15x8x4cm protective case.

The baseline kit is expected to have roughly 40h of battery life for the Pocket (2000 mAh battery), and 60h of battery life for the Slim Pro (3000 mAh battery).

The downside to the baseline kit is that it does not include GPS, and requires the devices GPS. An improved version is based on the T114, which also comes with significant battery improvements. However, this setup costs about $85 to produce.

• Instead of the Heltec V3, the Heltec T114 V2 with GPS is used. This device also has a much better battery lifetime, even with the 2000 mAh battery. Testing suggests battery life of about a week even with GPS and an active mesh.
• The case is the Pocket GPS case. It is a little difficult to assemble, and it's recommended to superglue the halves together.
• The same Pocket antenna and battery options above are used.

There are a ton of options for mesh hardware, and certainly not limited to teh above. The baseline model was chosen for ease of assembly and being cost-effective, while the enhanced model is chosen for built-in GPS capability. A comparable node that is not home-manufactured might be the Seeed SenseCAP T1000-E. Alternatively, a standalone messaging device that can be equipped with a GPS is the LilyGo T-Deck. The T-Beam Supreme with the L76K is another option for a portable node that works well as a base node.

The devices are flashed with the Meshtastic firmware. There is a secondary channel available to add to the device to allow encrypted communication between the people in our group. It is important that the device is not configured as a "licensed operator," as that will disable encryption. The default primary channel is also maintained, as that allows basic position information to be propagated normally. The defaults for position reporting should be fine, but you can adjust them.

In order to maximize the effectiveness of the mesh, the default primary channel should be kept. Any nodes belonging to the group should be added as favorites so they can be easily found. However, a preconfigured secondary channel (which requires that the channel encryption key be shared ahead of time) allows secure communications over a secondary channel.

If a contingency occurs, the secondary channel can be used for status reports and propagating information such as VHF/UHF frequencies for higher-bandwidth traffic using shorter text messages.

The secondary channels also allow configured to allow precise location reporting, but this is dependent on the hardware (and whether it has precise location support) and requires a manual update request. The general theory is that if precise locations are needed, the people we are locating are in a generally fixed position, and regular precise location updates aren't required—so the burden of manually requesting position updates isn't bad.

Another thing to think about in a contingency is the device role (configured in Settings → Device → Role). The default that should be used 99% of the time is the "Client" role, which will still route and rebroadcast messages. Othe roles to consider for special circumstances include:

• client mute: same as client, only without rebroadcasting. Useful when there is an active client with better signal and you are in a congested area.
• client hidden: client will not rebroadcast or send regular telemetry / position updates. It will reply if directly messaged, though, and will respond to position requests.
• tracker is optimized for sending position reports. It works well for keeping track of family members in the event of an emergency.
• tak and tak tracker are designed to be integrated with ATAK systems (via the Meshtastic ATAK Plugin) for communication in coordinated operations.

Note that the nodes do not strictly require a phone or other device to be connected if they have GPS; they can be configured ahead of time, and the only difference is that the node can't be used to reply to messages. Most of the devices have screens, however, so they can act as "tracking pagers." Whoever is carrying them will be able see incoming messages, just not respond if they don't have a connected mobile device.