Communications & Connectivity
The paths from a sensor to a place you own: radios, wires, bridges, meshes, and what an endpoint actually is.
On the bench
The Endpoint Starter Coming
Every build in this book ends the same way: readings land at an endpoint you own. This is that idea productized: what a webhook is, what MQTT is, and the shortest honest path from "the sensor works" to "the record is mine," starting on our live Test Bench before you own anything.
Outdoor Point-to-Point Wi-Fi Bridge Coming
A pair of outdoor directional radios that carry your network a mile or more on a clear line of sight. One aims at the house, one at the barn, and every node in the far building joins your network like it were in the next room.
RS-485 / Modbus Wired Runs
When radio is the wrong answer, this is the wire that is right: RS-485 carries readings hundreds of meters through electrical noise that would eat anything else, and Modbus, the industrial protocol that rides it, is what charge controllers, VFDs, and weather stations already speak. The Modbus reader program is in the Software Library.
Meshtastic Mesh Radio (XIAO + SX1262) Coming
Thumb-size LoRa radios running the open Meshtastic firmware: off-grid text between vehicles, buildings, and hands, no cell service, no infrastructure at all. Each node relays for the others, so coverage grows with every radio you add.
The Cellular Fallback Link
For the site with no wire, no line of sight, and no neighbor: a cellular modem carries the readings out over the phone network. The last resort that is always available, sized honestly — a monitoring node needs pennies of data, not a streaming plan.