Welcome to another thrilling installment of “I Probably Just Need Fresh Air” — the series where I stay indoors to build gadgets that tell me how indoors I really am.
This time, we’re going smaller, smarter, and cooler. Literally.
You ever find yourself needing to know the temperature or humidity inside a sealed jar, a mysterious box, or your suspiciously damp living room? So you go online and buy one of those cheap plastic sensor thingies — the ones that come in a suspiciously generous 10-pack for $1.99.
And then, surprise! Each one shows a completely different reading. Accuracy: somewhere between a wild guess and a weather forecast from 1812.
But you’re not giving up. Oh no. You upgrade. You get the “premium” version. A sleeker box! With a better screen! Twice the price — same garbage readings.
Still optimistic (and now slightly poorer), you go all-in on the “Smart” ones. You know, the ones with an app, Bluetooth, graphs! Except… the app updates once an hour, if it doesn’t crash, disconnect, or demand the blood of three AAAs before functioning again.
Been there. Bought the t-shirt. Returned the t-shirt because it didn’t have Wi-Fi.
So I said enough.
Let’s make something better. Something you can trust. A system where you can deploy as many tiny sensor nodes as you want, see all the data in one slick web interface, and — here’s the kicker — run for months on a single charge. Yes, charge. Like a modern human. No “One-Gazillion Batteries!” (read that in your best Dr. Evil voice, please).
Each device will cost around 12-15 Euros, fit in the palm of your finger, and deliver actually accurate readings. No drama.
The master plan:
- A central hub acts as your data brain: receives info from all the sensors, stores history, names, whatever you need.
- It runs a web server, accessible from any device on your network.
- It’s clean, simple, lightweight, and doesn’t look like a spreadsheet from the 90s.
We’re using the Seeed Xiao ESP32C6 — a tiny, mighty microcontroller that sips power like it’s rationing coffee in a post-apocalyptic wasteland (as low as 15 μA in deep sleep).
Add a 250mAh lithium battery, and with some clever power management, it’ll last months. Yes, even the tiny battery is doing its part.
For the sensing part, go wild — SHT3X, SHT4X, AHT1X — all are supported, all are accurate. We’re talking ±1.8% humidity and ±0.3°C temperature precision. Enough to actually believe the results.
Everything’s mounted on a custom, teensy PCB. The size limit? Basically just the battery. Welcome to the eternal struggle of all modern mobile devices.
So. Are you in?
Ready to build your own swarm of eco-friendly, no-nonsense, hyper-accurate indoor climate sensors?
Let’s do it. Keep reading and build your own Mesh of Joy™.
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~ TheBrightKnight