Building a GOES-16 Antenna out of Trash, Cardboard and Foil Tape

Over on his YouTube channel saveitforparts has uploaded a video showing how he was able to modify and old DirectTV satellite dish found in the dumpster with cardboard and foil in order to receive images from the GOES-16 geostationary weather satellite.

I wanted to download images from the GOES-16 weather satellite, but didn't have a big enough satellite dish. So I made one out of an old TV dish, cardboard, and aluminum tape! Amazingly this actually works, and I was able to pull live pictures of the earth off the satellite in geostationary orbit! The cardboard won't last long-term, so I'm looking for an antique C-band dish that I can set up as a more permanent solution. However, for a cheap and expedient ground station, this worked pretty well!

Satellite Ground Station With Trash, Cardboard, and Foil Tape!

SMOG-1 PocketQube Satellite Successfully Launched and in Orbit

Thank you to Zoltan Doczi (HA7DCD) for submitting news about the successful launch and first reception of the SMOG-1 PocketQube Satellite (which is only 5x5x5cm in size). The pre-launch press release by Tech University of Budapest is available here, and the SMOG-1 Facebook page provided additional updates.

Back in April 2020 we first heard about the launch of SMOG-P which was the first functioning 1-PocketQube satellite, and was designed to measure electromagnetic pollution (electrosmog) from space. SMOG-1 is the successor to SMOG-P and it carries a similar mission to measure electromagnetic pollution generated by human activity in space around the Earth. Interestingly it also carries a magnetically lossy material under it's solar panels which is to act as a brake, reducing the 18-25 Orbital lifespan, thus reducing space trash after the primary mission is complete.

According to the receive and decoding instructions provided by Levente Dudas, SMOG-1 can be received with a simple satellite antennas, such as a handheld Yagi, Turnstile, Dipole or quadrifilar-helix antenna. The telemetry frequency is 437.345 MHz with callsign HA5BME. For the radio an RTL-SDR connected to a Raspberry Pi can be used, and the telemetry decoding software can be found on GitLab

SMOG-1 can be tracked here, although Zoltan mentions that the TLEs may not yet be accurate for several more days or weeks, as was seen with the launch of SMOG-P as well. The reason is that it is difficult for the NORAD radars to see these tiny PockQube satellites which is required for TLE generation.

Preorder Sale: Active L-Band 1525-1660 Inmarsat and Iridium Patch Back In Stock for $44.95

We have just received stock of our new L-band active patch antenna design. The antenna is designed for receiving RHCP L-band satellites such as Inmarsat, Iridium, GPS and other satellites that transmit between 1525 - 1660 MHz (please note that you cannot use it for weak signals that require a dish like HRPT or GOES). The antenna comes as a set with a large suction cup, 3M RG174 extension cable and bendable tripod to help with mounting. Preorder pricing is US$44.95 including free worldwide shipping to most countries shipped from our warehouse in Shanghai. At the end of this week (extended for one more week!) pricing will rise to the standard cost of US$49.95. Amazon stock will require time, and won't be in for at least 6+ weeks.

Please see our store to order the unit

Like our previous patch design, this is an actively amplified antenna as it contains a built in low noise amplifier which takes power from a 3.3 - 5V bias tee. This power is available from from our RTL-SDR Blog V3 dongles, and other SDRs like the Airspy, HackRF and SDRplay. It also has a built in SAW filter after the LNA to help reduce terrestrial interference.

Compared to the previous design the new patch is larger (175 x 175 mm) with higher gain and wider radiation pattern. This allows for much easier pointing of the antenna and for much stronger signals. The upper frequency range has also been extended to 1660 MHz from 1625 MHz. The included suction cup is also much larger allowing for the patch to point at more angles without being restricted by the window. The patch is enclosed within a new weatherproof plastic enclosure. 

L-Band Patch with Accessories
L-Band Patch Mounting Examples

The screenshots below show the patch receiving various signals like AERO, STD-C and Iridium

Inmarsat Reception
Inmarsat Reception
Airspy Showing Patch Bandwidth
GPS "hump" visible

Usage Tips

  • The antenna should be used with one meter or more of coax cable. It may perform poorly if the RTL-SDR is placed right at the antenna due to interference. If you want to run very long cable, then low loss coax should be used. 
  • The patch can be used flat, or angled towards the satellite. Angling it towards the satellite will yield significantly higher gain.
  • If you have very strong cell phone interference in your area, try using the patch a bit lower to the ground, and use buildings to block the interfering signal.
  • If you want to mount this on a car roof, you can use a standard mag-mount camera adapter.
  • When using the suction cup, ensure you wipe down the cup and the window surface before sticking it on. Have a backup plan in case the suction fails.

What can you do with this antenna?

Project Horus 55: Live Video from a High Altitude Balloon

Project Horus 55 was a project that involved creating a high altitude balloon with payload that could broadcast live video down to ground station observers, as well as creating the ground station receive hardware. On March 7th 2021 the balloon was launched and ground station observers successfully received the live video.

The transmission hardware onboard the balloon was a Raspberry Pi Zero which captured and compressed the video, and a LimeSDR Mini which broadcast a DVB-S signal at 445 MHz. Power amplification was provided by an 800mW LDMOS amplifier. On the ground station side, RTL-SDRs were used as the receiving hardware and SDRAngel as the software. Although high gain auto tracking Yagi's were used by the main ground station team, it's interesting to note that the balloon chase team were also able to receive the video with a simple vechicle mounted turnstile.

In the video below Mark VK5QI who was one of the people behind the project discusses the setup before the launch.

Live Amateur TV from 100,000 feet!

The video below shows the launch and some of the live video received.

PiccoloSDR: A Simple SDR From a Raspberry Pi Pico

The Raspberry Pi Pico is a $4 microcontroller board. Recently radio amateur Luigi Cruz discovered that the ADC on the Pico could be used as a simple direct sampling software defined radio, with a bandwidth of 250 kHz. The idea is that the ADC data is made available to a PC connected to it's USB port via emulated TCP/IP protocol. On the PC side, GNU Radio is then used to process the received ADC data, turning it into an SDR.

Applications of a direct sampling SDR with only 250 kHz are limited, as it's only possible to receive up to the LF band, and there are not many signals that low in frequency. However, it is an interesting project that can be used to demonstrate a simple SDR. If you're interested in trying it out, the code is available over on GitHub.

PiccoloSDR Project - Using the Raspberry Pi Pico RP2040 as an SDR - First Test with GNU Radio.

[Also seen on Hackaday]

GPU Accelerated RTL-SDR Radio Interferometer Code For Radio Astronomy

Evan Mayer (@millijanskys) has recently released some code called “effex” that allows you to use two RTL-SDR dongles as an interferometer for radio astronomy and other experiments.

The hardware used is two RTL-SDR Blog V3 dongles with synchronized oscillators via the selectable clock headers, two 1420 MHz filtered LNAs, a splitter and noise source consisting of a 50 Ohm load and wideband LNA, and a NVIDIA Jetson Nano GPU single board computer. We note that Evans code should also run on our KerberosSDR with some modifications to enable the built in noise source during calibration.

To add to this Evan wrote to us explaining how this code might be used:

You could start to do some basic interferometric imaging by adding more coherent channels. This is exactly what Daniel Estévez just did with USRPs and GNU Radio at the Allen Telescope Array.

Did you see the “picture” of the supermassive black hole shadow released by the Event Horizon Telescope collaboration in 2019? The “ring of fire” or “donut” image? Daniel’s image and that image were created by “aperture synthesis.”

In aperture synthesis, the signals from each pair of antennas distributed across an area can be cross-correlated to measure one component of the 2D Fourier transform of the radio brightness distribution on the sky. But, you need coherent receivers (or REALLY good time stamps) to cross-correlate the signals from the antennas. Get enough pairs of antennas, and you can start to more fully sample the 2D Fourier space of the sky brightness distribution, which you can then use to reconstruct a real image.

This is how distributed radio arrays like the EHT work, as well as localized ones like ALMA or LOFAR.

Receiving Video Directly from a SpaceX Falcon 9 Rocket + Scott Manley Video

Last week we posted about how several users on Reddit & Twitter worked together to receive and decode text telemetry from the SpaceX Falcon 9 rocket launch using a HackRF, 1.2m dish with custom 2232.2 MHz feed and GNU Radio. In that thread it was hinted that the text telemetry was only a small portion of data contained in the entire signal. It turns out that the remaining data is the SpaceX engineering video feed which is often shown in the official live coverage streams.

Over on Reddit user /u/TRGFelix writes how he was able to receive and decode the video with his own low cost setup involving an Airspy Mini SDR, TV MMDS downconverter and the ubiquitous low cost WiFi grid dish that we've often used for GOES satellite reception and for Hydrogen Line radio astronomy. The software used was the SatDump decoder created by /u/Aang253 which builds on the research done by @r2x0t:

So today at 10:21UTC i got my own recording of Falcon9 video feed downlink on S band 2272.5MHz and with u/Aang253's software SatDump i could easily decode it from the recording straight down to mxf, avi or mp4 video file! Even with very simple recieving setup!

Setup used for receiving was simple wifi grid mesh dish antenna (100x60cm) on a tripod with old MMDS TV downconvertor and Airspy MINI. here is a photo of the setup few minutes before launch But of course its doable without convertor with SDR such as HackRF , two SPF5189Z LNAs and same antenna or even TV dish with DIY S band feed!

Software used for recording was great performing opensource SDR++ by u/xX_WhatsTheGeek_Xx link here https://github.com/AlexandreRouma/SDRPlusPlusS oftware used for decoding was u/Aang253's Satdump software which i will link later as it still needs readme written and confirm it runs without bugs! UPDATE - LINK: https://github.com/altillimity/SatDump

Original MXF video together with CADU file and I/Q file recording 6MSPS int16 here. https://files.altillimity.com/Falcon%209%20OK9UWU/

TRGFelix is also on Twitter as @OK9UWU and he has posted images of his setup, and part of the video he decoded. TRGFelix notes that he is working on a tutorial which we are very eager to see!

It's extremely interesting that we can see views of the liquid oxygen floating around inside the stage two tank which is not shown during the official live streams.

As a bonus, this story was also covered by the very popular space YouTuber Scott Manley who has put out a great video popularizing the discovery and touching on a few interesting points such as how SpaceX may be legally required to encrypt these videos in the future (but hopefully not!).

How Amateur Radio Fans Decoded SpaceX's Telemetry & Engineering Video

CENOS Antenna Design and Simulation Software Looking for Testers

Back in March 2020 we posted about CENOS, a company creating a new antenna modelling and simulation design package. Back then they were offering applications to beta test the software for free. CENOS has now reached V1.0 status, and they are now wanting to enroll another 300 testers. The benefit to the testers is that they will receive a 90% lifetime discount on the software, and testers who provide lots of active feedback will be granted free licenses.

CENOS Antenna Design version 1.0 will be available for closed testing starting from March 17, 2021.

During the free 14-day testing trial, users are expected to share their feedback about the software and usability, thus making an impact on further software development. 

In reward, they will get a generous discount or lifetime-free-licenses (for best contribution), once the software is available for public use (we expect to launch it shortly after rigorous testing completes).

More details will be announced on March 17!
 
Sign up here:
Software benefits
 
​CENOS is fast-to-learn and easy-to-use specialized antenna design simulation software for budget-sensitive customers.

CENOS integrates FreeCAD geometry editor to handle geometry of any complexity, provides built-in utilities for handy design of microstrip antennas and arrays, feed networks, wire antennas (including import of NEC files), and arbitrary 3D structures. FreeCAD also allows to import CAD files from external editors like Autodesk Inventor or similar.

CENOS ensures automatic meshing, as well as allows building manual mesh of any detalization level in the specially designed FreeCAD workspace.

For antenna calculation, the current software version utilizes FEM solver to provide accurate simulation for geometries of any complexity, including multi-port, high Q and other cases. Already now, CENOS R&D is pointing to combining the FEM solver with MoM and FDTD methods to provide a unique, optimized (fast and accurate) solution for any particular case.

CENOS provides very powerful visualization capabilities that includes full visualization of fields and graphs powered by Paraview, spreadsheet for data like S11, VSWR, reflection coefficient, etc, and pdf report.

That all makes CENOS a good alternative to well-known general purpose software like HFSS, CST, FEKO and Comsol for budget-sensitive customers looking for specialized antenna design simulation software.
Software functionality
• One-stop software: from CAD geometry to full visualization of results and analysis
• Desktop (on-premises) installation for Windows 7-10
• CENOS leverages open-source tools to ensure full stack of CAD/CAE software: FreeCAD, GetDP, ParaView
• User experience optimized for RF antenna design
• Supports the use of CAD geometry files prepared by any design program (.step or .iges formats)
• Pre-defined templates for basic antenna geometries
• Full-stack geometry editor powered by FreeCAD
• Material database, possibility to add and save custom materials

Simulation capabilities
• Wide range of antennas, antenna arrays, geometries of any complexity, inhomogeneous structure
• Finite element method (FEM) solver optimized for high frequencies
• Lumped port type, multiple ports (feeds) with phase shifts
• Frequency diapason (wide, multiband) 
• Ports: S11, VSWR, power, reflection coefficient, impedance, reactance, and resistance
• Fairfield pattern: directivity (gain), radiation intensity
• Antenna: Electric field, magnetic field, vector plots 
• Frequency-dependent dielectric constant and loss tangent
 
… all you need for antenna design in an easy-to-use way, because this is the software specialized on RF antenna design with full spectrum of necessary functionality. And we are constantly working to add more value.
 
Hardware requirements
You don’t need a supercomputer to run antenna design simulations with CENOS. Intel i5 or i7 (or similar) are good enough. The faster processor you have, the faster calculation will go.

We recommend to have at least 16Gb RAM to calculate 3D cases, 32Gb is better. Actually, the more RAM you have, the bigger (more complex) 3D geometries you can simulate. Some of our customers use 128 Gb machines and that’s like for rocket-science-cases. MS Windows OS.
CENOS Antenna Simulation