Living near Zurich airport, Daniel Eichorn wanted an easy way to show his house guests what planes are flying near him. Usually he opens up his Flightradar24 app on his phone, but he wanted a more permanent always on display. To do this Daniel has built an ESP8266 based OLED display which automatically displays the ADS-B flight information of aircraft outside his window. The ESP8266 is a very cheap and highly popular WiFi module which can give a microcontroller access to WiFi networks.
Daniel feeds his locally received ADS-B data to adsbexchange.com using a Raspberry Pi and RTL-SDR. While actually feeding ADS-B data with an RTL-SDR is not required to make the ESP8266 module work, this step ensures that he has good local coverage of his area. The ESP8266 module then queries the adsbexchange.com database via WiFi for information about planes in his area and displays the information on the OLED screen.
In previous posts we also showed how the ESP8266 could be used to transmit data like NTSC TV in a similar way to Rpitx.
In his new video CNLohr demonstrates that AM radio can be broadcast by attaching a short wire antenna to the ESP8266 ethernet output, and then using an RTL-SDR to receive one of its harmonics at 150 MHz. He shows that by varying the size and speed of the packets he can change the received tones, and even create notes to play music. This essentially gives a simple way to ‘hear’ ethernet.
Broadcasting AM Radio with Ethernet on the ESP8266
The ESP8266 is a $7 WiFi module that can be used to give any microcontroller access to a WiFi network. It is designed for creating Internet of Things (IoT) devices and has various features such as it’s ability to host it’s own web applications. The ESP8266 also has a I2S output with DMA support. By hooking up this I2S output pin to a short wire, YouTuber CNLohr has demonstrated that he is able to use the ESP to broadcast full color NTSC TV. This works in a similar way to how PiTX works, by using the pin to modulate a radio signal. CNLohrs code note only broadcasts color NTSC, but also provides a full web interface for controlling it.
In the first video CNLohr shows off his initial work at getting the NTSC output working and in the second video he shows color working. Later in the second video he also uses an RTL-SDR to check on the NTSC spectrum that is being output.
Amazon Alexa is a smart speaker that can be programmed to control home automation devices via voice commands. For example, Stuart Hinson wanted to be able to control his wirelessly controlled blinds simply by verbally asking Alexa to close or open them. Stuart's blinds could already be controlled via a 433 MHz remote control, so he decided to replicate the control signals on an ESP8266 with 433 MHz transmitter, and interface that with Alexa. The ESP8266 is a cheap and small WiFi capable microchip which many people are using to create IoT devices.
Fortunately replicating the signal was quite easily as all he had to do was record the signal from the remote control with his RTL-SDR, and use the Universal Radio Hacker software to determine the binary bit string and modulation details. Once he had these details, he was able to program the ESP8266 to replicate the signal and transmit it via the 433 MHz transmitter. The remaining steps were all related to setting up an HTTP interface that Alexa could interface with.
If you're interested, we've also previously posted about another Alexa + RTL-SDR mashup which allows Alexa to read out ADS-B information about aircraft flying in your vicinity.
Over on YouTube a video titled “Hunting Rogue WiFi Devices using the HackRF SDR” has been uploaded. The talk is given by Mike Davis at the OWASP (Open Web Application Security Project) Cape Town. The talk’s abstract reads:
Rogue WiFi Access Points are a serious security risk for today’s connected society. Devices such as the Hak5 Pineapple, ESP8266-based ‘throwies’, or someone with the right WiFi card and software can be used to intercept users’ traffic and grab all of their credentials. Finding these rogue devices is a very difficult thing to achieve without specialised equipment. In this talk Mike will discuss the work he has been doing over the past year, to use the HackRF SDR as a RF Direction-finding device, with the goal of hunting down various malicious RF devices, including car remote jammers.
The talk starts off with the basics, explaining what the problems with WiFi devices are, what the HackRF and SDR is, and then goes on to explain some direction finding methods that Mike has been using.
Hunting rogue WiFi devices using the HackRF SDR – Part 1 of 2
Hunting rogue WiFi devices using the HackRF SDR – Part 2 of 2