What MQTT over TLS costs a battery node
A node that reconnects for every report pays for a TLS handshake every time. Often the handshake, not the reading, sets the battery life.
Telemetry, Power
Lab notes
What we learn on the bench, written down so you don't have to learn it the hard way. Each note says where its numbers come from.
Designing devices for load-shedding
Power cuts, dips, inverter switch-overs and whole neighbourhoods coming back at once. A checklist for devices that live on an unreliable grid.
Firmware, Reliability
Reading analog sensors on the ESP32 without fooling yourself
The ESP32's ADC is good enough for most sensors, if you respect which pins, which range, calibration and impedance.
Firmware, ESP32, Sensors
Why your ESP32 dev board can't reach 10 µA in deep sleep
The datasheet says microamps. The meter says milliamps. The chip is fine; the board around it was built for the desk.
Power, ESP32