I’m a big fan of the TinyTX sensors and source code from Nathan Chantrell. By using a low cost small microcontroller (Attiny84) and the RFM12b transceiver, it is possible to build a whole grid of sensors in your home.

I have two devices running for some weeks now. Those are manually made by soldering all wires together which does not look very good and takes some time to build. Nathan published the TinyTX version 3 which offers exactly what I was looking for. More available connections and some space for experimenting. I’ve ordered 10 prints from seeedstudio to create more sensors at home.

Currently my plans are:

  1. Temperature & Humidity in livingroom (implemented in Wireless LCD Display)
  2. Outdoor Temperature & Humidity using DHT22 sensor
  3. Addict Temperature & Humidity using DHT11 sensor (inaccurate but it works for now)
  4. Temperature & Humidity sensor in the kids bedroom
  5. Temperature & Humidity sensor in the bathroom
  6. more temp sensors
  • Waterflow sensor using piezo elements to detect someone taking a shower 
  • Add LDR sensors to detect light
  • Mailbox (reallife) sensor to detect mail being delivered