Tagged: satellite

A Small 11.2 GHz Motorized Radio Telescope with TV Dish and RTL-SDR

Thank you to Kaustav Bhattacharjee for writing in and submitting to us his project, where he created a small 11.2 GHz motorized radio telescope with a TV dish and an RTL-SDR. A full description of Kaustav's work can be found in a white paper he wrote on behalf of the Department of Physics at the Indian Institute of Technology Roorkee. In summary he writes:

Briefly put, the hardware Setup comprises a 66 cm parabolic dish, a standard Ku-band LNB with bias tee power injection as the frontend, an RTL-SDR V3 tuned to 1.45 GHz (due to downconversion) as the receiver and a Raspberry Pi 5 handling SDR data (via GNU radio) and stepper motor control (using GPIO pins). A heatmap of the southern sky at 0.9° resolution, showing a belt of geostationary satellites, is the primary result of interest!

We also want to point out that his rotor setup involves several 3D printed gears driven by two NEMA17 stepper motors. However, Kaustav notes that the long term resolution is limited due to cumulative backlash errors from the open-loop control scheme.

Kaustav's 11.2 GHz RTL-SDR Radio Telescope
Kaustav's 11.2 GHz RTL-SDR Radio Telescope
Geostationary satellites visualized with the radio telescope
Geostationary satellites visualized with the radio telescope

SignalsEverywhere Android Project Updates: Satellite Tracker, HackTV NTSC Transmitter, OBS To HackTV, PacketShare and More

Recently, Sarah Rose Giddings (aka SignalsEverywhere) has been actively developing several radio and SDR based projects for Android, and she would like to provide an update on them.

First, as mentioned in a previous post, Sarah has been developing APRS.chat, an online mailbox system for APRS messages sent over RF. She has also been making progress on various other projects, including various useful Android apps, which she has updated interested people on in her latest livestream.

Hangout Chat | Linux | HackRF NTSC Transmission | Android APPS and More!

Some of the links to the Android software she's working on have been provided below:

Works with Benshi Protocol Radios (VR-N76 UV-PRO etc)

Stuff Created After The Livestream

Help beta test Play Store Releases (Benshi Dash, Benshi Commander, APRS Chat): https://docs.google.com/forms/d/e/1FAIpQLSfNTrCBofQYam6f6CrZ8XxTxZw2vlOiaD6ehGs5NBOAbKkHWw/viewform?usp=header

Screenshots from Sarah's HackTV NTSC Transmitter
Screenshots from Sarah's HackTV NTSC Transmitter

Amateur Weather Satellite Reception Beyond NOAA POES

With the recent decommissioning of NOAA POES (NOAA-15, NOAA-18, NOAA-19), many amateur weather satellite hobbyists might be asking themselves if the hobby is now dead.

While NOAA POES satellites were the easiest stepping stones into amateur weather satellite reception, the hobby has seen massive strides in enabling easier reception of other satellites over the past few years. Furthermore, in the near future, various new satellites are scheduled for launch, which should be receivable by amateurs.

Over on his blog, Jacopo has created a detailed post showing what satellites amateur hobbyists can still receive on the L-band and S-band. Some receivable satellites include Meteor-M,  Metop, Arctic Weather Satellite (AWS), STERNA, Elektro-L, GOES, EWS-G, Jason-3, UVSQSat-NG, DMSP, HINODE, ISS DATV and Proba 2.

While almost all of these satellites (apart from Meteor-M's LRPT 137 MHz signal) require a satellite dish and L-band, S-band, or X-band feed, recent products like our Discovery Dish can make setting up an L-band or S-band system significantly easier.

The Meteor-M series of satellites
The Meteor-M series of satellites

Moving SatDump Towards V2.0.0

Over on the SatDump blog developers Aang23 and Lego11 have recently uploaded a post discussing their plans to move SatDump towards Version 2.0.0. SatDump is currently the most comprehensive and popular software for SDR users wanting to decode images and data from satellites. 

The developers note that their update frequency has slowed down recently due to their focus on V2.0.0. The new version introduces significant under-the-hood changes that will make SatDump easier to manage and develop in the future, and also focuses on improved documentation.  

Users of SatDump will also see an improved GUI, new functionality such as crop, an SSTV decoder, support and improvements for a wide range of satellites, any many other improvements discussed in the post. 

We note that V2.0.0 has not yet been released. The post notes that at some point in the near future they will begin merging the new V2.0.0 branch into master, followed by frequency alpha releases, before finally releasing an official V2.0.0. 

SatDump V2.0.0 ALPHA with new GUI
SatDump V2.0.0 ALPHA with new GUI

Saveitforparts: Receiving NOAA-15 One Last Time

Over on YouTube Gabe from the saveitforparts channel has uploaded a new video discussing the decommissioning of NOAA-15 and NOAA-19. We also previously posted about this topic a few days ago, if you are interested.

NOAA-15 was scheduled to shut down on August 12, 2025, but due to anomalies with NOAA-19, the decommissioning date of NOAA-15 has been extended by a few days until the week of August 18th. NOAA-19 has recently been experiencing transmitter failures, and it may be impossible to receive signals from it at the moment, despite its expected decommissioning date of August 19, 2025.

In the video, Gabe also rushes to try and receive signals from all transmitters on NOAA-15 one last time, setting up VHF, L-Band, and S-Band receivers. He experiences some issues with weak signals, interference, and recording failures, but ultimately succeeds in capturing all three signals during one of the final passes of NOAA-15.

US Government Shutting Down More Weather Satellites

Discovery Drive: An Affordable Antenna Rotator Crowd Funding Pre-Launch Page now Active!

We're happy to announce that the pre-launch page for our "Discovery Drive" automatic antenna rotator is now live! Please sign up to be notified of when the crowdfunding page goes live as the price will be reduced by at least $100 during the campaign.

Discovery Drive is an automatic antenna rotator that is designed to be used with our Discovery Dish product, as well as similarly sized antennas such as Wi-Fi grid and Yagi antennas.

Discovery Drive with Discovery Dish Mounted
Discovery Drive with Discovery Dish Mounted

A motorized rotator allows you to use a satellite dish or directional antenna to track and receive signals from polar orbiting satellites, which quickly move across the sky. It also lets you switch swiftly between geostationary satellites without manually realigning the dish. 

Examples of polar-orbiting weather satellites that you can track include NOAA POES, METEOR-M2, METOP, and FENGYUN. Depending on your location, you may also have access to other interesting satellites that dump data over specific regions. Amateur radio operators can also use Discovery Drive to track amateur radio satellites with Yagi antennas.

Discovery Drive
Discovery Drive

Discovery Dish is designed to be easy to set up and use. Unlike many other rotators on the market, no external controllers are required. Discovery Drive has a built-in ESP32 controller, and control can be commanded over WiFi or serial from rotctl-compatible software such as SatDump, GPredict, and Look4Sat on Android. 

Features and Specifications

  • Up to 125 kgcm (12.25 Nm) of torque
  • ESP32 control board
  • ± 1.5° of accuracy
  • -360° to +360° Azimuth range, 0° - 90° elevation range
  • 1.5 RPM Azimuth speed, 0.25 RPM elevation speed
  • 12 V power input (either barrel jack or USB Type-C Power Delivery)
  • Wi-Fi connectivity with browser-based web UI
  • Serial over USB data connectivity or Wi-Fi data connectivity
  • Low power draw (< 10 W, can be powered with PoE+ supplies and still have power left over for powering a single board computer and RTL-SDR)
  • Robust worm gear-locked output drives
  • Direct rotctl compatibility over Wi-Fi (compatible with programs that implement the rotctl protocol, such as SatDump, GPredict, and Look4Sat on Android)
  • Hamlib compatibility (EasyComm II protocol)
  • Waterproof outdoor enclosure
  • Open source ESP32 firmware 
Discovery Drive Inside Look
Discovery Drive Inside Look

TechMinds: Testing out the SkyRoof Software for Receiving and Tracking Amateur Radio Satellites

At the beginning of this month, we posted about SkyRoof, a new software program by VE3NEA for receiving and tracking ham radio satellites with an RTL-SDR and other SDRs.

Recently, Matt from the TechMinds channel uploaded a video on YouTube testing out SkyRoof. In the video, Matt explains the software's various sections and features, such as Doppler correction. He then goes on to demonstrate various audio voice signals being received with the software.

SkyRoof - A Brand New Satellite Tracking Software With Built In SDR Software - This is awesome!

Updates To NOAA-18 Decommissioning: NOAA-18 Has Now Shut Down

A few days ago, we posted news that NOAA-18 was to begin decommissioning steps effective immediately due to a recent transmitter failure. Multiple reports have now confirmed that NOAA-18 has indeed shut down as of 1740 UTC 06/06/2025.

The usaradioguy.com blog has further updates for those who are interested. The official notice from NOAA can also be found here. Interestingly, it appears that NOAA-18 will not be de-orbiting as it lacks the required propulsion system to do so. So it will remain in orbit as space debris.

A user using a hobbyist station in Sweden also captured the shutdown remotely during APT image reception, as shown in the image below.

Farewell and thanks for your long service NOAA-18!

The final NOAA-18 APT pass captured by SA2KNG in Sweden, and processed remotely by Thomas:douwes.co.uk
The final NOAA-18 APT pass captured by SA2KNG in Sweden, and processed remotely by Thomas:douwes.co.uk