KrakenSDR - WOW! Amazing Direction Finding Tests : Part 2 

You're very welcome for the videos. Definitely worth a look at the KrakenSDR!

The acquisition time was amazing. We were surprised and delighted just how quickly it had us going in the right direction!

If the Kraken is too costly, the 4 channel Kerberos works, too.

RU-vid is great for learning more about the hobby, and for finding others with similar interests. I'm glad you found the channel.

Oh, excellent. I'm sure the Kraken will be great for that!

And indeed it did.

Oh, that's interesting, I didn't even notice the accent thing at all. It does happen when I talk on the radio to Irish & English friends as well. All part of having lived in various places I suppose! But yeah, the signal hunting was a blast.

It's another interesting development in the world of SDR :-)

Yes, I believe the antennas must face a certain direction relative to the front of the vehicle. Can't 100% remember now. I'll recommend you check the wiki on that. Spacing is certainly critical too.

It will certainly allow for some passive radar experiments, but I don't think I'll be experimenting with that.

Happy hunting! I hope you quickly find the offending signal. Set up can be a little daunting, but the results are amazing.

Excellent news. Any particular signals you'll be searching for?

@@FrugalRadio Well to be honest I've never done this before so I guess any signal I can find. New to all things radio, I bought this on a whim back during Covid

Ah, ok. There are loads of signals out there, so you'll probably have plenty to choose from, especially if you're in a city.

@@FrugalRadio That's the part I was worried about being from a small town in BC. Should be fun but might run out of signals quick

@@FrugalRadio I think I bit off more than I can chew.. I have too many hobbies and this radio stuff is a bit over my head. Will be selling my Kraken on Facebook marketplace as I don't think I will have the time to use it.

I'm not sure. Was there something you had in mind?

@@FrugalRadio Anything other than finding stationary licensed transmitters. Nobody is going to buy it for that.

What would you be interested in finding?

You're welcome!

That will depend on frequency, terrain, and many other factors. My experiment was in the prairies. Not many hills around etc. Also you'd need to be able to create appropriate curves, which wouldn't work if you are too far away. You'd have to experiment and see. The device can also be used in network configuration. Eg several devices set up in a city, networked together. That might be another approach.

A very special welcome to you, friend! Thanks for subscribing!

Yeah, it would be nice to compare to professional systems, but I don't have access to one. Some of the pro gear costs $100,000+!

Hmm, I'd never have thought of that! Thanks for sharing!

@@FrugalRadio I once drove as a wedding car so I tried it to put flowers on my car.

Yes, as long as there was a transmission source. The KrakenSDR team put out a video last year when the device was pre-production showing it display a moving DOA graph of a moving toy train.

I don't know if they've finished the software yet, but you can use it as a passive radar to track any vehicle, even if it doesn't have a radio transmitter since anything large and metal is reflecting signals from transmitters in the area.

Yes, I'm sure some people will buy it specifically for passive radar experiments.

Hi Paul. I believe the GPS portion is essential for determining the relative bearings, and is what makes this platform so accessible. You could always read through the documentation online, as it's all available there, or contact the KrakenSDR team to ask specific questions. I have found them to be quite responsive.

Thank you for your reply!

You can display the output from the Kraken on a laptop, yes. However the system is designed to use a phone or tablet for the GPS positioning and tracking. With the various devices combined, the performance is excellent. You could reach out to the RTL-SDR Blog team for more specifics, but I think the minimum equipment would be a computer and a phone. The computer would probably need to be running a flavour of Linux.

The transmission is strong, because I can receive it about 20km away.

Yes, that would be one of the uses for the Kraken, if the interfering signals are within its range.

Yeah, pretty amazing unit. Great fun.

You can use a laptop instead of a Pi, but I think you need a phone to provide GPS location data throughout the process. If you're familiar with Linux, you should have no problem substituting in a laptop. I didn't try any simulcast sites as I'm sure it would become very confusing to the unit!

@@FrugalRadio thank you for the quick reply, I have no Linux or pie experience I was trying to make it more simple by just using a laptop but maybe that makes it more complicated. There are several simulcast sites in my area, maybe an inline switchable attenuator would be key as far as reducing interference from the other sites as you get closer to the site you're hunting for.

A good place to ask about that might be on the RTL-SDR.com blog site. If you post a question there about using it in a simulcast environment, you may get a response from the developer. Try on the article here : www.rtl-sdr.com/frugal-radio-krakensdr-part-2-vehicle-direction-finding-tests/

Yes, this is a huge leap forward with regards to price, and getting the equipment into the hands of hobbyists. I only know 1 person who has used a professional version (costing several hundred thousand dollars). He worked for a cell phone company here, and it was used to trace interference near cellular sites (mostly people's boosters, but sometimes cable TV boxes / systems).

@@FrugalRadio I have been interested in buying a KrakenSDR to play around with. I am one of those people who have used government owned DF's to locate transmitters. I have almost 30 years experience with HFDF and mobile DF. In the military we had multiple single line of bearing (LOB), fixed receivers and plotted the approximate location of the transmitter on a map board. With a portable DF the LOB was determined from an aural null. For medium to long range DF, the LOB was determined with a half propeller pattern displayed or a CRT, the DF equipment have a sense function, i.e. it could determine which direction the signal was arriving from. This was in the early 1970's. Approximate locations were determined and if necessary and possible, airborne DF was used to determine a better approximate location. I worked as a civilian government employee operating DF equipment from the late 1980's until after the mid 20's As a civilian DF operator the fixed DF LOB was also determined by a pattern displayed on a CRT. The pattern was a full propeller pattern as the DF did not have a sense function. The fix was determined using a computer program which provided an approximate latitude and longitude of the location. Close in mobile DF was used to find the actual location, when necessary or possible. Not all exact locations could be determined, due to the transmitter being in the air, at sea, or outside of the United States. No airborne DF was available for use. The civilian government mobile DF's I operated were first Doppler systems, with two antenna, that basically, with LED's, showed the signal was coming from left, right, straight ahead (or behind) or a variation of those. That was changed when the annular slot antennas were developed that could receive signals in a 360 circle. These had a compass rose of LED's that showed the signal direction arriving at the mobile unit (a vehicle), with North being relative to the front end of the vehicle, West the left, South the rear, and East the right of the vehicle. Annular slot antennas were still used when the mobile DF equipment was changed to computer control of a radio receiver and software modifying a GPS mapping program to show LOB's laid across the map and originating from the icon of the GPS location of the vehicle at the time the LOB was shot. North was still relative to the front end of the vehicle. One aspect of the mobile DF platforms was the lack of accuracy of a LOB, while not mobile. They were more accurate while moving. I have wondered about that aspect in regard to the KrakenSDR. I don't know about the two antenna Doppler system, but the others had costs from about $20,000.00 to several hundred thousand dollars! Some reasons for the high cost was the development of the system, the in house construction of most components, and the limited number of units built.

@NevilofMars very interesting to hear from you. Thanks for sharing your experience. You've put a lot of time into the DF field! I'm sure you'd have fun with the Kraken. You can even use them in a networked capacity these days. Exciting times for hobbiests to have access to this level of DF ability at this kind of price.

@@FrugalRadio FYI I made my post before viewing the video as sometimes, I read the comments first. I am impressed with how fast the KrakenSDR and mapping system determined the location of the transmitters. A suggestion, if possible, set the KrakenSDR to write bearing LOB's (you called them plots or plot lines) less often so that your map is not overwritten with solid blue. Depending on how often the program writes the LOB, say if it is one LOB every second, or one LOB every 10 seconds, then you may only need one LOB every 15 or 30 seconds. This, only if the plotting software does not need each LOB to be displayed on the map, n and the lessor number of LOB's written to the map does not interfere with the determination of the transmitter location. With the DF that I used, we had the choice of manually shooting a LOB or having continuous LOB's with a similar result of the LOB's covering the map and hiding streets or roads from view. LOB's were not necessary all the time. Like the DF that had a compass rose of LED's, the computer controlled DF also had a compass rose display indicating the direction of arrival of the radio signal, related to the front of the vehicle. Most of the time I would manually shoot one or two bearings when I first heard the signal, drive a few minutes and shoot more LOB's looking for the LOB's to cross on the map, giving me an idea of where I needed to drive. The system I used did not plot a location for the transmitter, I had to use the DF for signal direction and drive up to the location of the transmitter, then visually identify it. I suspect that if your transmitter was mixed in with other radio towers, then you will have a more difficult time determining what antenna you are chasing. Based on the little information I have of the KrakenSDR DF system at this time, I would consider it to be a superior mobile radio direction finding system to any that I have worked with!

Hi Tom, thanks for getting in touch. My suggestion would be to contact the RTL-SDR guys for support with the Keberos. I haven't ever used one. If it works similarly to the Kraken, make sure you boot devices in the correct order. I forget which way round they need to be booted, but if the order is wrong, the devices don't connect to each other.

You can use Linux!

@@FrugalRadio what about windows, I heard you could use some VMware through windows based laptop or am I mistaken?

According to the wiki pages, you can use a virtual machine in Windows.

@@FrugalRadio thanks for what you do.

The software will work with your Android, but you will need a computer in line as well. If it's a windows PC you may need to run a Virtual Machine using Linux.

@@FrugalRadio thank you

Fort Saskatchewan is where we made this video. But I may also have been referring to Edmonton.

Let me put it this way. A local telecom employee has requested an automatic Direction Finding unit for his work. The firm refused the request since they were quoted $250,000. This item performs many of the same functions, and does so with great accuracy, for under $600. It is certainly the more frugal option!

@@FrugalRadio grasshopper looked at this blindly, I will strive to open my eyes master! 😉😆

It's hard to remember everything when recording "on the road".

Copy that

Im going to looking around 750-850 mhz. Little confused about the distance from center for doa. The excel sheet is a little intimidating.

I've got no idea. That could definitely be an interesting use of the hardware!

The US military can do all of that with satellites already.

The US can do all that with their remote monitoring sites, the satellites are needed only when the transmitters are out in BFE where there are no remote receivers sites.

Easiest way of dealing with that would be to have someone else drive. As for the reasons to have one : it's really for hobbyists who want to experiment with direction finding or passive radar.

I don't think that's quite true. Using the app on screen is perfectly legal if it's in a holder. So far as I can tell once it's set it's just the same as using sat nav. "You can use devices with hands-free access, as long as you do not hold them at any time during usage. Hands-free access means using, for example: a Bluetooth headset voice command a dashboard holder or mat a windscreen mount a built-in sat nav The device must not block your view of the road and traffic ahead." Taken from www.gov.uk/using-mobile-phones-when-driving-the-law#:~:text=It's%20illegal%20to%20hold%20and,videos%2C%20or%20browse%20the%20web.

What's the point? So you can call in artillery to their location. Duh.

I have done this work with older & less sophisticated gear & it took a lot longer because I was alone, bearings being taken only while stationary. With this KrakenSDR I could work faster & with safety in mind.

So you can train an antenna (such as a yagi) on the location of a transmitter if you are in a fringe reception area. Or identify the source of an interfering signal. Or just to see what you can do with SDR. In my case, finding the user of a system was very helpful. I have since updated the Radio Reference database, and now anyone who lives in the area will be able to monitor the system with more information, and download the correct data onto their scanner.