4x RTL-SDR R820T2 Receivers
A wideband noise source that can be switched in software
USB Hub so only one USB connection is required
A calibration board for synchronizing samples with the noise source
A shielded metal enclosure
Internal cables for connecting the two boards and noise source
The KerberosSDR has been around a while now, (in point of fact: end of life as of 2022) but it still is one of the most popular products on the SDR market, put simply its unique!
Four RTL SDR's are nestled together in one package give you an opportunity to develop an RF direction finding solution with functions on par with much more sophisticated kit. Using little more than 4 tiny antenna's, an Android phone and a Raspberry Pi you can triangulate a signal to a specific area in some cases a few meters!
including:
Pinpointing the source of VHF/UHF noise, pirates, interference, jammers, unknown signals etc using radio direction finding (RDF)
Using passive radar to monitor aircraft that do not transmit ADS-B
Monitoring vehicle or marine traffic with passive radar
Direction finding for amateur radio fox hunts
Determining the location of rescue or stolen asset beacons
Combining multiple small dishes to create a large dish for radio astronomy via beam forming.
Using the four tuners as standard RTL-SDRs. e.g. two for trunking, one for ADS-B and one for weather satellites.
Pitfalls might include inexperience with Linux, drivers, getting everything linked together however with some elbow grease and patience tracking down your first RF source is a hoot!!
getting the KerberosSDR running on a windows machine for initial testing and evaluation is not as straight forward as one might think, but I have found the wonderful software from Simon Brown (https://www.sdr-radio.com/console) works realy well and for an absolute treat when it comes to noise reduction SDR# offers some of the best results I have ever heard, best of all both are free.
EI7KN gave me some realy useful links to software that helped me replace the incorrect drivers MSW installed called Zadig (https://zadig.akeo.ie/) then as if by magic a plethora of devices appeared amongst the device manager list.
Once the drivers are sorted, you can switch the individual SDR devices in and out as you need them, so for the developers amongst us this offers fabulous opportunities and flexibility especially when it comes to forms of diversity reception or direction finding.
In conclusion, if you are looking for a Raspberry Pi project or perhaps develop some interesting android/linux application then this offers oodles of fun in a silver tin.. Grab one while you can as they are becoming harder to find, the KrakenSDR has replaced it but does have a hefty price tag..
Good luck with your project, whatever it maybe.. Gaz