KrakenSDR now Shipped to the Majority of Crowd Supply Backers
If you weren't aware of it, KrakenSDR is our RTL-SDR spinoff project and is a 5-channel coherent RTL-SDR that we have successfully crowdfunded for over on Crowd Supply. KrakenSDR is the successor to our previous 4-channel coherent product called the KerberosSDR. With a radio like KrakenSDR that is capable of coherence between channels, interesting applications like direction finding and passive radar become possible. You can also use it as five independent RTL-SDRs should you chose to.
We wanted to note that all units preordered through the Crowd Supply crowd funding campaign are now at the Crowd Supply / Mouser warehouse, and the majority have already been shipped out to customers!
Additional units for new purchasers are in a mixture of production and freighting and will be available for fulfillment as soon as we can. We are constrained by supply and production time, so if you're interested in a KrakenSDR, please get your order in so that you have an earlier place in the queue.
Other Recent KrakenSDR Updates
Wiki Manual: Our Wiki manual and guide is up at https://github.com/krakenrf/krakensdr_docs/wiki. It covers topics from what you need to get started, radio direction finding theory and background, antenna array setup, KrakenSDR Web-GUI software guide, Android App guide and a Passive Radar guide.
GNU Radio: We have recently released a beta version of a KrakenSDR GNU Radio block and examples at https://github.com/krakenrf/gr-krakensdr
Install Scripts, VirtualBox Images, Docker: For general vehicle based direction finding, which is the most popular application, we recommend using our premade Raspberry Pi 4 image for easy almost plug and play setup. But to ease installation on other computing devices (especially as the Pi 4 stock is non-existent at the moment due to the supply chain crisis) we've now created an automatic Linux install script and a Virtual Box image which can be run on Windows or Linux host machines. Third parties have also released a Docker container. See this page on our Wiki for more information.
Customer Feedback: We've also had some great customer feedback so far with one user submitting examples of his success in locating transmitters like a 162 MHz NOAA weather station, and various fox hunt beacons.
Arrow Antennas: For fixed site direction finding installs, Arrow Antennas is now shipping their 5-element dipole antenna array.
If you're interested in the latest KrakenSDR updates, please follow us on the Crowd Supply mailing list, and keep an eye out for our official krakenrf.com website releasing soon.
I have had my KrakenSDR for about two weeks now and really love it. The build quality is excellent, I was not expecting how solid and sturdy it is. I have to say, this is a massive improvement over my KerberosSDR. Mine has been running almost 24/7 in passive radar mode and has remained solid. I am really looking forward to testing out DF, but so far, this a fantastic device!
I had tried a manual install on an x86 laptop running Ubuntu 20.04, and wasn’t able to get the web interface to work. I just tried the install script and am essentially in the same situation. The krakensdr_doa software is running, but I get page not found errors when accessing port 8080 on the same laptop. I’ve got a thread running in the Kerberos forum here, as well as the SDR forum at radioreference – looking for advice.
I just did this last night, in my case I was not providing enough power to the unit and I also needed to uninstall librtlsdr-dev and rtlsdr first before the script. Check your logs the heimdal firmware folder, you’ll probably find the rtlsdr is failing due to power and keeping the page from loading.
I don’t think that’s it. I’m able to access all the receivers separately, and I’m using a pi-4 power supply. But I did try the script install on a second 20.04 computer, and while I got the same results, on a whim I started the android/computer wifi connection anyway and I AM able to access all of the control menus via the android phone kraken app. I just can’t access them on the host computer…..
Replied to you on the forums, please check.
I like what you guys have done with hardware, really good to get it this small cheap package. I think calibration has really been overlooked though and I’d imagine as a result the accuracy wouldn’t be very good. If the arrow antennas are roof mounted and you have maybe 5m of cable, how are you calibrating for the effects of mismatched cable paths (cable connectors etc). Ideally it would be cal’d in an anechoic chambers for DF however that’s not really feasible here. If you included some hardware on the PCB, signal source, directional coupler etc you could auto perform S11 phase measurements on each channel like you do for noise and really cal out the effects of the cable. Perhaps this could be done with the noise source (not sure). Currently with no way to do this I’d imagine the DF accuracy would be pretty crappy.
The antenna array cables need to be identical in length to some precision tolerance depending on the frequency. We’re finding that for signals below about 1 GHz ~1 cm cable tolerance is fine. The chain in terms of connectors etc needs to be identical on each cable.
In the DOA software it’s also possible to use s1p tables from a NanoVNA or other VNA to fully cal out the cables if you want.
We could implement some S11 measurement into the Kraken at additional cost…but also for compliance we can’t really be selling something that could transmit cal signals out through the antenna arrays, when those antenna arrays could be deployed in places where even low power transmissions could be problematic or illegal.
So basically, for 1GHz+, or if you want ultimate accuracy, use phase matched cables, or measure your cables + array on a cheap VNA and give the s1p tables to the software.