A Review of WarDragon: A Portable SDR Kit

Over several years Aaron (@cemaxecuter) has been working on DragonOS, a popular Linux distribution that comes preinstalled with many different programs for software defined radios. A Linux distribution like this takes the hassle out of having to figure out how to compile and install various SDR programs, some of which can be quite tricky to get running. 

Recently Aaron has also been working on WarDragon, which is a set of components that he's carefully tested and put together as a ready-to-use portable SDR kit. At its core is an Airspy R2 software defined radio and x86 Mini PC that comes with DragonOS pre-installed. It also includes a USB hub and GPS dongle, as well as an HDMI dummy plug for enabling remote desktop. Everything is held together by a 3D printed frame, and enclosed in a plastic carry hard case, with the external Ethernet, USB-C, and power ports routed to the outside of the enclosure.

Aaron kindly sent us a WarDragon for an honest review. We note that we do not get to keep the WarDragon, and it will be forwarded to someone else after this review.

WarDragon Outer Enclosure
Inside WarDragon (Intel PC hidden underneath)
WarDragon with an LCD screen connected

Getting started with WarDragon is simple. Open the hard-shell case, connect an antenna to the Airspy, remove the dummy HDMI plug, connect a monitor to the HDMI port and a keyboard/mouse to a USB port, connect 12V power, and start the mini PC. A few seconds later DragonOS has booted, and you can run any of the programs pre-installed. And there are certainly a lot of programs available to play with as shown below.

List of software pre-installed in DragonOS

To get started with running it remotely we followed the instructions on the desktop to install OpenSSH, and ran the Rustdesk appimage stored in the 'post install' folder on the desktop. This allowed us to connect remotely to the unit via Rustdesk, a remote desktop interface. From there we were able to run software like SDR++, GQRX, and anything else that was preinstalled.

Aaron notes that every WarDragon will come with a free license for SDR4Space which is a command-line SDR tool for satellites. It can be used for scripting various operations, such as "recording IQ samples, predicting satellite passes and to start a record for a specific satellite and correct doppler at the same time".

The KrakenSDR software is also pre-installed on WarDragon, so the Airspy can easily be swapped out for a KrakenSDR too (or almost any other SDR as well). You can also add extra RTL-SDR units on the USB hub if desired.

Once you're done simply unplug everything and put the HDMI dummy plug back in. Close the enclosure up and you're ready to get on the move again.

One minor concern we have is that while the components are contained with the 3D printed frame, the frame itself is not held down inside the enclosure, so it can move a little during transport. Not a big deal if you are sensible about carrying it, but if you are expecting to throw the box around, something could eventually go wrong. Aaron also notes in the instructions that care should be taken to not leave WarDragon exposed to direct sunlight or in a parked car to avoid the 3D printed insert from warping. This could probably be solved by printing in a material like ABS.

Performance

The mini-PC included with WarDragon runs a 12th Generation Intel Alder Lake - N95 that can turbo up to 3.4 GHz, has 8GB of RAM, and a 256GB SSD built-in. These specs are powerful enough that the system is very snappy, software opens quickly, and software runs smoothly, even at the max 10 MHz bandwidth the Airspy supports.

These x86 mini-PCs appear to be quite a bit more powerful than their similarly priced ARM counterparts, but they do draw more power. The mini-PC running SDR++ and Airspy at 10 MHz oscillates around 20-30W of power draw, whereas a Raspberry Pi 5 running SDR++ only draws 5W.

What We'd Like to See Improved

Because the carry case is fully sealed when closed, the mini PC inside cannot be run when the case is closed, as there would be no airflow for cooling. We'd like to see some thought put into adding an external fan, and indeed Aaron has noted that in future versions he will be adding this. However, adding a fan does come at the expense of water tightness but we don't imagine many people would be throwing this in a body of water. As long as rain resistance is kept it should be alright.

We'd also like to see the SMA port brought out to the side, so an external antenna can be connected with the enclosure closed.

We can also imagine that some users might like to see a more expensive version that comes with a small screen and keyboard/mouse as part of the combo too. Aaron does note that the most common use case for operating via SSH or remote desktop via a field laptop though.

Price Review / Value

The Wardragon consists of the following components:

  • Beelink Mini PC (N95 8G+256G) - US$159 on Amazon.
  • Airspy R2 - US$169 on iTead.
  • Condition 1 11" Carry Case - US$36.99 on condition1.com
  • Other parts (cables, USB hub, USB GPS, HDMI dummy plug, outside connectors, 3D printed frame) - $US35 (estimated)
  • SDR4Space License - $US???

So that's a total of US$400 in parts (not including shipping costs) plus a bit of value from the SDR4Space license which is usually obtained on an inquiry-only basis. WarDragon currently sells for US$580. So for the extra $180, you are paying for the time to preinstall of DragonOS, drill the external mounting holes, 3D print the mount, the build time, testing time, and the ability to get support directly from Aaron himself. And we can't forget to mention the time Aaron puts into creating YouTube videos for WarDragon.

Obviously, if you are on a tight budget it would make sense to try and build your own system. But overall we think WarDragon is not a bad deal if your time is worth more and you just want a portable system to get up and running with DragonOS ASAP.

Flipper Zero Starts a Petition To Fight Canada Ban

Back in early February we reported about how the Canadian government is making plans to completely ban the Flipper Zero, and popular pentesting tool. The wording from Dominic LeBlanc, Canada's Minister of Public Safety, also implies that software defined radio devices could also be banned.

The reason for the ban is because the Canadian government claims that Flipper Zero and 'consumer hacking devices' are commonly being used as tools for high tech vehicle theft. However, as mentioned in the previous post, this has been debunked.

The team behind Flipper Zero have recently started a petition on change.org to stop the ban. At the time of this post the petition has already reached over 8,000 signature. The team have also penned a comprehensive "Response to the Canadian government" blog post, explaining why the ban makes no sense. In the post they debunk the myth of Flipper Zero being used for car theft, and show the real way high tech car theft is being done.

Doing 50 Things with RTL-SDR in One Week

Thank you to Blinry who recently wrote an article about how they set themselves a challenge to find 50 things to do with an RTL-SDR in one week. Blinry writes:

Last week, I attempted the challenge to try to find 50 things to do with an RTL-SDR device in a week!

It was quite an adventure: I received satellites and radio from the other side of the world, I went on a hunt for a radiosonde, and I invented a method to communicate using the NFC tag in a library book!

I used the RTL-SDR Blog V4 for everything, plus the antenna kit, plus a long piece of wire.

Congratulations Blinry for achieving your goal and taking us on a whirlwind ride through the different applications of RTL-SDR!

NOTE: We note that Blinry's website appears to be a bit slow to load, presumably because or the large image file sizes, and because his article has become quite popular. If you're having trouble loading the images and videos, maybe try again at a later time. Alternatively, thanks to user pbnjeh on Hackernews you can try loading directly from Archive.org or https://archive.is/ZHnfV.

Blinry Receiving and Tracking a Weather Balloon using SDRAngel and an RTL-SDR Blog V4

Meteor M2-4 has not failed – it is still in the testing phase

Thank you to Robin OK9UWU who wanted to point out that the recently launched Russian Meteor M2-4 weather satellite has not failed. There have recently been rumors and videos being spread online claiming that the satellite has already failed as the LRPT and HRPT signals are currently offline.

However, the satellite is still in a testing phase and was only briefly transmitting images for a few days after launch. It is difficult to find official updates from Roskosmos, the Russian space agency, but Robin explains his thoughts on what is happening:

The satellite in question, Meteor-M N°2-4 did not fail. The reason for both the LRPT and HRPT transmitters to be off is that the primary instrument (MSU-MR) is currently undergoing a routine cleaning process to get the IR channels up and running correctly.

It's completely normal.

Other reason why it's off could be that they are testing the MeteoSAR instrument (2-4 is the first sat of this series to have this), hence why unnecessary radios might have been taken offline.

It's important to understand that these satellites are being used to do actual science, weather forecasting etc. They require careful testing and calibration which might take some time. It's not just for "cool imagery".

For example, it took months to get the VIIRS instrument running onboard of the NOAA-21 satellite.

Keep calm and nerdy!

spaceintel101.com's infographic about the Meteor M2-4 Launch
spaceintel101.com's infographic about the Meteor M2-4 Launch

Saveitforparts: Building a Satellite Antenna from an Emergency Blanket and a Rotator from an old Security Camera Mount

Over on his YouTube channel, 'saveitforpaarts' has uploaded two new videos. The first shows how he was able to build a very cheap satellite antenna for GOES satellites out of an umbrella and a metallic emergency blanket. The blanket is simply spread over the inside of the umbrella, creating an RF reflective surface. Then a linear feed with LNA and amplifier is placed at the feed point. The makeshift dish works, though the SNR is marginal, and he is only able to receive slightly corrupted images from GOES satellites.

Satellite Antenna Made From Emergency Blanket

In his second video saveitforparts builds a satellite dish rotator out of an old thrown away security camera pan/tilt mount. The mount is hacked to be controllable via an Arduino microcontroller. 

I Built A Cheap Satellite Tracking System From Spare Parts

Great Scott Gadgets URTI: Phase Two Progress Report

Over on their GitHub, Great Scott Gadgets, creators of the popular HackRF SDR, have created a phase two progress report for their upcoming URTI product. URTI (Universal Radio Test Instrument) is their next generation software defined radio which will work not only as a full-duplex SDR transceiver, but also as a vector network analyzer, spectrum analyzer and more.

In the phase two update they note that they have completed fabrication of an initial prototype board and have confirmed that all components on the board are functional. They note that much of phase four was already completed in parallel, which means the firmware and gateware development is also close to completion. So hopefully we will see more updates soon.

More information about URTI can be found at greatscottgadgets.com/urti.

URTI (Universal Radio Test Instrument) First Prototype Board

IndiaRocketGirl Receives NOAA-19 Weather Satellite Images with a Tape Measure Yagi Antenna

Over on her YouTube channel IndiaRocketGirl (@VU3BIZ) has posted a video showing how she was able to receive weather satellite images from the polar orbiting NOAA-19 weather satellite at 137 MHz.

She uses a home made four element Yagi antenna with elements made from a tape measure. This allows the elements to be easily folded down for transportation. A phone running the Heaven's above app is used to help track the satellite in the sky as it passes over, and then SatDump and an RTL-SDR Blog V3 running on a laptop is used to decode the signal into an image.

IndiaRocketGirl notes that in her next video she will show how to make the Yagi antenna that she was using. In a previous post IndiaRocketGirl also showed how she was able to receive geostationary FengYun-2H S-VISSR signals.

How to Receive Real Time Images from Low Earth Orbit Satellites | India Rocket Girl | NOAA-19

KrakenSDR Radio Direction Finding Setup and Tutorial YouTube Video

Over on YouTube user Skyler F has posted a video showing him unboxing his KrakenSDR, and KrakenSDR antenna set, and then setting it up and taking it on a test to find the location of a cellular tower. In the video Skyler shows how to set up the antenna array using the paper spacers, how to connect the KrakenSDR to a Raspberry Pi, and how to configure the Android direction finding app.

If you weren't already aware, KrakenSDR is our 5-channel coherent radio based on RTL-SDRs, and it can be used for applications like radio direction finding. It can be purchased on Crowd Supply.

Kraken Radio Direction Finding Unit Setup Tutorial and Demo