KN0CK Miniature HF Upconverter Rev. 4 Now for Sale

Update: KN0CKs products are now available at http://www.kn0ck.com/HF_SDR/.

The fourth revision of the miniature HF upconverter for the RTL-SDR by KN0CK is up for sale, now that revision three has just sold out. Revision four has a 120 MHz oscillator, and is capable of receiving the 6m band.

Check out the release post over at KF7LZE’s blog, and the product sales page at the Easy-Kits store.

Receiver Opened Up

Tracking of Low Earth Orbit Satellites with the RTL-SDR

Over on travisgoodspeed.blogspot.com, Travis shows us an interesting project where he set up a satellite dish that automatically tracks and receives moving satellites, such as those in low earth orbit. Travis uses an old satellite dish salvaged from a maritime vessel as the receiving dish, a RTL-SDR for receiving the signal, and a BeagleBone for motor control and running rtl_tcp. The dish motors use satellite positional data from celestrak.com to automatically track a desired currently visible moving satellite.

tracking_satellite

GR-Air-Modes GNU Radio ADS-B Decoder for the RTL-SDR Updated

Reddit user bistromat has recently updated the GNU Radio based Mode S ADS-B decoder gr-air-modes. He has added Google maps view, a legend and zoom support to the azimuth map view, and has restructured the underlying code. The new gr-air-modes requires the latest GNU Radio 3.7 version.

Check out the original post here (with cute puppy included), and clone the latest version via github from the following link.

https://github.com/bistromath/gr-air-modes

gr-air-modes google maps screenshot

 

Decoding RDS in GNU Radio with the RTL-SDR

DangerousPrototypes.com have brought to attention a GNU Radio RDS decoding project from the website at Anotherurl. Check out the original post here. Anotherurl uses a GNU Radio Companion flowgraph and a .NET program to decode FM RDS messages. RDS is an acronym for Radio Data System, which is used in FM radio transmissions to embed information such as radio station and programme/song information. Some conventional FM radios display this information on an LCD screen. The popular SDRSharp SDR receiver also has RDS decoding built into it’s FM receiver already, but a GNU Radio implementation is very useful for learning how RDS works.

GNU Radio RDS Decoder

via dangerousprototypes.com

Combining Multiple RTL-SDRs for Improved ADS-B Reception

Over on Gough’s Tech Zone blog, Lui has posted a writeup about his experiences with combining multiple remote RTL-SDR ADS-B receivers to privately obtain ADS-B aircraft data from multiple antenna’s at multiple locations. His setup is shown in a diagram below. He has one remote antenna connected to a Raspberry Pi, one to a remote PC and one to his main PC.

Combining Multiple ADSB Receivers

In order to do this he used the Linux based dump1090 ADSB-B decoder and hub software on his main PC. Lui was even able to compile and run the ADS-B hub portion of dump1090 on his Windows PC using Cygwin, but was unable to get the decoder part to work. It doesn’t matter though because the dump1090 hub can receive data from any ADSB decoder, such as ADSB#. His results look very promising as can be seen by the timelapse of plane traces in the image below.

nearairport

Lui also has some other interesting ADS-B + RTL-SDR posts that you should check out where he tests ADS-B reception with a Mini R820T dongle.

rtl_acars.c Compilation Install Video

Yesterday we posted about the command line rtl_acars ACARS decoder. Today on YouTube, Pawel Janowski has posted a video showing how to download, compile and run the rtl_acars.c code on Linux.

Pawel has also posted the compilation instructions on his blog (in Polish but the console commands are easy to discern from the text).

ACARS from DVB-T (RTLSDR)

RTL_ACARS Console Acars Decoder for RTL-SDR

On the Osmocom mailing list, Andreas has posted his work on a console based ACARS decoder for the RTL-SDR. Check out the mailing list thread here, and original post here. The second post on the thread shows how to compile it under Linux. Andreas writes

I have combined “rtl_fm” with Thierry Leconte’s (GPL’ed) acarsdec library code and created “rtl_acars” which can directly decode ACARS flight info messages to the console. Confirmed to compile on OSX 10.6 (not possible for me to check if it also compiles under Windows and *nix). Feel free to add it as another proof of concept to your distro unless you consider it too much of a quick&dirty hack.

Only the source code is available, and you will need to compile it yourself. The code can be found here.