Over on his YouTube channel, TAKEAPART has recently uploaded a new video showing how to set up a cheap ADS-B FlightAware feeder using an RTL-SDR Blog dongle, and a Raspberry Pi Zero 2W. The Raspberry Pi 2W is a US$15 computer that is capable of running the PiAware ADS-B feeding software which uploads ADS-B data to the FlightAware.com flight tracking service. If you are a contributor to this service, you can get a Premium FlightAware subscription for free.
In the video, TAKEAPART shows how to install the PiAware software on the Pi 2W, and how to configure the PiAware settings. Finally, he shows it in action, receiving flight data with a homemade 1/4 wave ground plane antenna.
Cheapest ADS-B feeder RTL-SDR and Raspberry Pi Zero 2W (PiAware/FlightAware)
Over on the /r/amateursatellites subreddit, user elmarkodotorg is organizing a group megaprojection project. The Megaprojection Project seeks to create a composite of as much of the earth as possible from weather satellite images captured by hobbyists in a single day, via data from NOAA and Meteor polar-orbiting satellites. They will be accepting HRPT or LRPT data from either Nov 30 or Dec 1 (date yet to be confirmed).
Hobbyists can receive these satellites' LRPT and HRPT signals using an RTL-SDR and appropriate antenna setup.
If you want to contribute, you can join DerekSGC's Discord server, https://sgcderek.github.io, where coordination will be carried out. elmarkodotorg writes that currently, they have confirmed contributors with stations from the west coast of the US all the way over to the western edge of Asia. Currently, they are still hoping to find contributors from the Canary Islands, Turkey, Equatorial Africa, the general area of Indonesia, and Northern Australia. In a more recent Reddit thread, elmarkodotorg provides a link to a Google docs sheet, where you can also register interest.
Recently, on November 16 a test was carried out and they were able to successfully combine 24 images received across the world.
Megaprojection Nov 16 Test: 24 contributors from all over the world submitted HRPT and LRPT images received from their home satellite ground stations.
Thank you to RTL-SDR.COM reader David for letting us know about an excellent talk from Charles Lohr (@cnlohr) at the 2024 Hackaday Supercon about turning microcontrollers into radios by abusing their output GPIOs to create RF generators.
This talk explores ways to leverage every cycle of underpowered microcontrollers to get them doing the work of parts ten times their price, including operations normally done with dedicated radio hardware.
This is a concept we have seen quite often before in projects like RPiTX and Osmo-FL2K which turns a Raspberry Pi and cheap VGA adapter respectively, into an arbitrary RF signal transmitter with no transmit components required.
In his talk Charles Lohr takes this concept further, showing how almost any microcontroller like an ATTiny85, ESP8266, CH32v203, and ESP32-S2 can be turned into a transmitter. In the talk, Charles shows how he used the I2S bus on an ESP8266 to transmit NTSC color video to a TV and transmit LoRa via his LoLRa software. He then notes that he was able to use the ESP32-S2 to transmit LoRa over 2.5 miles away.
Finally, Charles shows how the CH32v203 microcontroller can also be used as a receiver. With some code he wrote he is able to display the received signal on an FFT computed directly on the CH32v203, and even have a web interface to tune to specific frequencies and playback AM audio.
Hackaday Supercon 2024 - Microcontrollers Are Just Radios in Disguise - Charles Lohr
CNLohr's own YouTube video on the topic is also an excellent overview.
How far can I broadcast LoRa packets WITHOUT a radio? - LoLRa
Recently Majodi from NickStick Design wrote in and wanted to share with us some updates to the 'NickStick RF PowerSnitch' which we previously posted about in 2021. The PowerSnitch is a device that can be used to gain a quick insight into RF power levels. This is useful to help prevent exposing your expensive and sensitive RF equipment, like an SDR or VNA, to excessive power levels that could destroy it.
The device uses three LEDs to tell you the power level. Green means you have a safe power level, caution is yellow and danger is red. Yellow is set to around 0 dBm.
The RF PowerSnitch is available on Tindie or lectronz for US$29.50.
In a recent re-release, they replaced the micro USB port with a USB-C power port. They write:
Today, NickStick Design, an electronics design company for Makers, is excited to announce the launch of the RF Power Snitch USB-C, the newest version of its popular RF Power Snitch device. This updated model replaces the micro-USB port of the original with a USB-C port, making it more versatile and future-proof for today’s connectivity needs.
“Our original RF Power Snitch saved many VNA devices from destructive power levels” Majodi of NickStick Design said. “With the RF Power Snitch USB-C, we’re excited to provide users with an upgrade which aligns with modern connectivity standards.
Over the years many more products in the RF domain became accessible to radio enthusiasts. RF Power Snitch is a valuable companion tool for checking the potentially destructive power of the signals one would want to feed to their equipment. Because, although tools like the TinySA, NanoVNA or SDR devices are extremely affordable today, for a maker it is still an investment worth protecting.
That’s why our goal was to develop a low-cost companion device that can help makers and experimenters (especially beginners) in the RF domain to gain insight in the power levels of a signal before hooking things up to their valuable test equipment. As an extra to this we also made it possible to attach an MCU for doing power readings and plotting.
Recently some videos from this year's DEFCON 32 conference have been uploaded to YouTube. DEFCON32 was held on August 8-11, 2024 at the Las Vegas Convention Center. DEFCON is a major yearly conference about information security, and some of the talks deal with wireless and SDR topics.
During the Defcon 32 wireless village, there were several interesting talks and the full playlist can be found here. The talks include introductions to software-defined radio, information about synthetic aperture radar laws, transmitting RF signals without a radio, information about the allen radio telescope array, an introduction to the electronic warfare being used in Ukraine and much more.
Over on the DEFCON 32 main stage, there were also several interesting RF-related talks including:
RF Attacks on Aviation's Defense Against Mid-Air Collisions (Video)
Breaking the Beam:Exploiting VSAT Modems from Earth (Video)
GPS spoofing it's about time, not just position (Video)
MoWireless MoProblems: Modular Wireless Survey Sys. & Data Analytics (Video)
At the beginning of November, SDRplay Released version 5 of their SDRconnect software. SDRconnect is a relatively new official software platform for the SDRplay line of devices. Unlike their other software, SDRUno, SDRconnect is multiplatform and comes with a cleaner interface.
In their latest 'Preview 5' build the team has added various features listed below. In addition, a week after Preview 5 was released, they also released 'Update 1' which fixed several bugs. You can read about the changes in their Release notes, or via the screenshot below.
Previously, Charlie had already written a JavaScript browser app for ADS-B tracking with an RTL-SDR. To achieve this she used the WebUSB API, which allows USB devices to connect to JavaScript apps in a web browser.
Having recently purchased a HackRF she wanted to see if something similar was possible with the HackRF. In her post, Charlie shows and explains the JavaScript code required to connect to the HackRF from a Chrome browser, and how settings like gain, frequency and sample rate can be adjusted. She then shows how to use the Canvas API to visualize the received data. Finally, she shows how to use the File System Web API to record data, and ultimately retransmit the recorded data with the HackRF.
The replay attack itself is based on the rolljam idea. She uses two HackRF's, with one sitting closer to the car's receiver and jamming it, and another recording the car's keyfob. This prevents the car from incrementing the keyfob's rolling code, allowing it to be recorded and used again at a later time.
Charlie has also posted a video of her tests, which we embedded below.
Back in 2020, we posted a tutorial on how to set up a low-cost Hydrogen Line radio telescope using an RTL-SDR, LNA, and WiFi grid antenna. Since then we have seen similar setups successfully replicated in the community many times.
In a recent Hackaday post, we discovered a paper by Jack Phelps who has written an in-depth technical and scientific description of his attempt at Hydrogen line radio astronomy with similar equipment. His paper goes into deeper scientific explanations and describes the experiment and hardware setup in detail including some signal processing, observation, and calibration equations that might be useful for those looking to understand the science more deeply.
Jack Phelps Radio Astronomy Setup and some Results
