Here is a list of components needed to build a RFLink smart home automation gateway. The RFLink Open Source project makes it possible to make a clone of the radio RFXCom 433MHz radio gateway (or other frequencies) for about $12. The RFLink gateway allows you to communicate with home automation devices using radio waves. It works in both directions:
- It intercepts and decodes messages emitted by home automation accessories
- It mimics the original radio transmitter to control the accessories
It is a work of titan which is realized by developer Stuntteam for several years now. New products are constantly being added. You can check the compatibility of your home automation device here. The list is updated every time the firmware is updated.
You can support the project (which makes it possible to buy the new home automation equipment) by making a donation on the blog of the project.
To build the gateway you will need the following hardware
An Arduino Mega 2560
Each home automation device has communication protocol that requires code to decode and encode the frames. With each update, the firmware becomes bigger and bigger. So you need an Arduino with enough flash memory space. Nodo has therefore opted for the Arduino Mega 2560. The Arduino Mega 2560 has 54 I / O instead of 14 for a conventional Arduino. This allows multiple receivers (and transmitter) to be installed in different frequencies (315, 433, 868, 915MHz and 2.4GHz). A single gateway can therefore communicate with a heterogeneous radio home automation equipment park.
Or the compact version
A quality 433MHz radio receiver
To have a good reception quality, do not hesitate to take a quality receiver. Nodo recommends the Superheterodyne RXB6 module.
A 433MHz radio transmitter
No special recommendations for the radio transmitter. The XD-FST low cost modules FS1000A are well-known in Arduino projects and are perfectly suited to costing virtually nothing. To increase the range, you can weld an additional antenna on some PCBs.
To assemble the gateway, you can purchase the printed circuit board for the Arduino Mega2560 at the Nodo store. It costs about € and the delay is about 3 weeks. The other solution (more economical but less elegant) is to use a breadboard compatible with the Arduino Mega 2560 (classic or compact) model. Some Dupont jumpers will be enough to wire the radio modules.
To make the antenna, single copper wire with a cross section of 1.5 mm2 is sufficient. It must measure 17cm long for the frequency 433MHz.
Ready for assembly! Follow this tutorial which explains how to wire the radio modules, install the firmware and integrate your first devices under Domoticz. You may also be interested in these products: