Tagged: rtl2832

Receiving Starlink Signals with an RTL-SDR and Ku-Band LNB

Over on YouTube, dereksgc has uploaded a new video showing how to receive signals from Starlink satellites using an RTL-SDR and a standard Ku band LNB. Note that this setup simply receives the raw signals, and it does not allow you to connect to the Starlink service.  

In the video, dereksgc first introduces Starlink satellites and explains what signals they transmit, referencing a paper on the structure of the Starlink Ku-band downlink by researchers at the University of Texas. He notes that the signals are strong enough that a single LNB without a dish is sufficient for receiving them. An LNB is a feedhorn antenna, low-noise amplifier, and downconverter all-in-one. It converts the ~10.950 GHz Ku band signal of the Starlink satellites down to a frequency that the RTL-SDR can receive.

In the rest of the video, he shows a timelapse of signals being received. The signal's doppler shift can be seen and heard as the satellite passes over.

Receiving Starlink signals with RTL-SDR

PySpecSDR: A Text User Interface Based Python RTL-SDR Spectrum Analyzer and Signal Processor

Over on GitHub a new open-source program called 'PySpecSDR' by [xqtr] has recently been released. This is a full multipurpose SDR receiver program like SDR# or SDR++, but with the difference that it runs entirely with a text user interface.

PySpecSDR displays a real-time spectrum and waterfall via text user interface and has the ability to demodulate and play audio for FM, AM, and SSB signals. The software also includes features like a scanner, automatic signal classification (between digital, FM, AM), frequency bookmarks, AGC, recording capabilities, band presets, and a configurable display. It is completely controlled via keyboard shortcuts.

Currently, the first version supports RTL-SDR only, but there is another version being worked on in the repo called pyspecsdr-soapy.py. This version uses SoapySDR, and that should support almost every SDR. It appears that most SDRs should already be working, but there are still some quirks to be fixed.

Some PySpecSDR Screenshots
Some PySpecSDR Screenshots

The Design and Test of a Filtered Low Noise Amplifier for LRPT Weather Satellite Reception

Recently Salil (aka NUCLEARRAMBO) uploaded a blog post on his website detailing how he designed and tested a low noise amplifier (LNA) with a filter for 130 - 160 MHz, which is useful for improving reception for the Meteor M2 LRPT weather satellite. If you were unaware, an LNA can help improve the reception of an SDR by reducing the noise figure of the system, and by overcoming losses from long coax cable runs. The filter helps reduce the strength of out-of-band signals which if too strong, can desensitize and cause imaging on the RTL-SDR.

In his design, Salil used a PGA-103+ LNA chip which has excellent noise figure and OIP3 specifications. His blog post details how he designed the circuit around the PGA-103+, added a bias tee for power, and how he designed the filter.

In part 2 of his post, he details how he tested the LNA+filter combinations frequency response, input voltage range, noise figure, and bias tee with an RTL-SDR Blog v3 and a NanoVNA V2.

Salil's low noise amplifier
Salil's low noise amplifier

DragonOS: Setting up AISMon with WINE and Virtual Audio Sink for HackRF and RTL-SDR

Over on his YouTube channel Aaron, creator of the DragonOS image (a Linux image with many built-in SDR compatible programs) has uploaded a new video showing how it is possible to run the Windows only AISMon software on Linux, using WINE. WINE is a Windows emulator for Linux which allows users to run some Windows software on Linux.

In the video Aaron shows how to set up WINE on the DragonOS Linux image, how to run AISMon with it, and how to set up the Virtual Audio Cable sink which is required to pass the audio from SDR++ to AISMon. He also shows how he tests his setup using the AIS-Simulator software with a HackRF, and an RTL-SDR for receiving.

DragonOS FocalX Setup AISMon with WINE + Virtual Audio Sink (HackRF, RTLSDR, SDR++, AIS-Simulator)

Setting up the Cheapest FlightAware ADS-B Feeder with RTL-SDR and Raspberry Pi 2W

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)

Weather Satellite HRPT and LRPT Megaprojection Project Nov 30 – Dec 1

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.
Megaprojection Nov 16 Test: 24 contributors from all over the world submitted HRPT and LRPT images received from their home satellite ground stations.

Paper on Building a Low Cost RTL-SDR Based Hydrogen Line Radio Telescope

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
Jack Phelps Radio Astronomy Setup and some Results

Setting up an ADS-B Radar in a Vehicle Android Head Unit

Over on YouTube channel 'TAKEAPART' has uploaded a short video showing how he tracks aircraft via an RTL-SDR Blog V3 dongle and his car's Android head unit. The head unit is capable of running the ADS-B Radar App available on the Google Play store.

Once the app is installed, it's a simple matter of plugging in the RTL-SDR Blog V3 unit and running the app to start tracking aircraft.

How to ADS-B Radar in the CAR - Tracking Planes...