1 Technophile

After more than one year of usage of home automation (HA) I have seen that one critical point is the communication between the sensors/devices and the HA system.  There is several possibilities for that: Infrared 5,8ghz 2,4ghz 867mhz 433mhz wire ... And for each of these possibility we can have a huge amount of different protocols. The goal of this article is to draft a list of the 433mhz gateways that can be found. We will focus on 433mhz due to the fact that i n european countries 433mhz devices/sensors are quite easy to find and with a correct price. We will take the following citerias: Price DIY complexity Number of protocols taken into account Complexity of home automation integration And take a look at RFXCom, RFLink, 433toMQTTto433 ESP8266, 433Utils, Broadlink RM... I will put in green the keypoints of each gateway. E&R = 433mhz emitter and receiver, can be a FS1000A and a XD-RF-5V or a superheterodyne one (recommended)

Following my first build of an external garden sensor, here is a simplified version with temperature, humidity and battery voltage measurement for a baby bedroom [EDIT] feedback about the expected battery duration here The requirements are: cheap long battery life, the atmega328p run at 8mhz with minimal components and functions under 8€ wireless (433Mhz) with good range (2 walls to cross and 10 meters) Here is the final view attached to a lion for decoration: And a report from OpenHab displaying the sensor data: If you want more details about energy power consumption the first article on this subject is more detailled. Now let's see how to build this. Bill of material The sensors is based on atmega328p (3€),  a 433 Mhz transmitter (1,5€) , a DHT22 temperature and humidity sensor (4€), a 433 mhz antenna (0,18€) DIP socket adaptor for the ATmega (1€) an electronic prototype printed circuit board (0,5€) At total we...

Following discussions on the home assistant forum people gave me the idea to add Infrared communication to the 433mhz gateway.  The goal is to act as a gateway between 433Mhz sensors, infrared remote controls and a MQTT broker or between the MQTT broker and 433Mhz actuators, infrared devices, It enables to: receive MQTT data from a topic and send RF 433Mhz signal corresponding to the received MQTT data  publish MQTT data to a different topic related to received 433Mhz signal  receive MQTT data from a topic and send infrared signal corresponding to the received MQTT data  publish MQTT data to a different topic related to received infrared signal  It can be an interesting part in an home automation system so as to interface sensors and actuators (wall sockets), your tv, home cinema, hifi ... with software like  openhab  or home assistant . List of compatible RF sensors here [EDIT] all infos are now centralized into the github repository  ...

I have built an external sensor so as to monitor temperature, air humidity, soil humidity of my garden and the battery voltage. The requirements was: waterproof long battery life, the atmega328p run at 8mhz with minimal components and functions under 10€ wireless (433Mhz) with good range (2 walls to cross and 10 meters) Here is the final view: And some reports from OpenHab displaying the sensor data: Air humidity Soil humidity Air temperature We can of course imagine to use these values to control a water pump. Now let's see hpw to build this. Bill of material The sensors is based on atmega328p (3€),  a 433 Mhz transmitter (1,5€) , a DHT11 (1€) or a DHT22 temperature and humidity sensor, a soil moisture sensor  (1,6€), an electrical box (1€)  a 433 mhz antenna (0,18€) DIP socket adaptor for the ATmega (1€) an electronic prototype printed circuit board (0,5€) a recycled  tube At total we are around 10€ ...

Since several months I worked on setting up an home automation system for my house. The goal was to have an open system, with an important part of DIY work and second hand components so as to satisfy my curiosity about these new technologies. In this first article I will expose the architecture of the system , the bill of material and the software involved. These devices are maybe not compliant with your country regulations and norms, it is your responsability to verify this compliance. Bill of material: 3 * 433Mhz presence sensor 5€ = 15€ 3 * 433Mhz door sensor 4€ = 12€ 1 * 433Mhz smoke detector  8€ = 8€ 1 * arduino UNO clone = 5€ 1 * arduino ethernet shield W5100 = 6€ 1 * raspberry pi 2 or 3 = 40€ 1 * sdcard 8gb = 5€ 1 * 433Mhz receiver and  1 * 433Mhz transmitter   = 1.50€ 1 * siren 3€ 1 * 9V wall transformer (second hand) 1€ 1 * kit of 3 switch plug = 20€ 1 * DHT11 temperature sensor = 1.50€ 1 * old computer speakers = 5€ Leds and resistors <3€...