The Australian Silicon Chip magazine has written an article about a kitset for a 100KHz to 2 GHz receiver based on the RTL-SDR that they are selling. Note, you will need to pay in order to be able to read the entire article.
Completing the kit gives you a radio with two antenna inputs, a 5-band preselector, an RF amplifier and an upconverter for the HF bands.
Over on the Gough’s Tech Zone blog, Gough has posted about his experiences in trying to obtain an E4000 RTL-SDR. He found that finding a real E4000 on ebay was tough, with most vendors claiming to have “upgraded E4000s” which were in fact R820T’s.
The E4000 tuner is becoming rare as Elonics, the manufacturer has shut down. The newer, still in production R820T tuner is in many ways better than the E4000, but the E4000 is still useful for some applications that require the higher frequencies that it can tune to.
If you want an E4000, we know for sure that Nooelec sells a Terratec version that has the E4000 chip.
A Radio Astronomer by the name of Dr David Morgan has released a tutorial/paper he wrote detailing how he uses the Funcube dongle Pro+ as a tool for radio astronomy. The Funcube dongle Pro+ is a software defined radio similar to the RTL-SDR, with higher cost, but better performance in some areas.
Dr Morgan uses his Funcube dongle with the SpectrumLab Windows software, which is a specialized audio analyzer. For the hardware, David uses a 3m focal plane dish antenna and a 1200 MHz high pass filter.
The paper goes into good detail about some of the technical side of radio astronomy, shows how to calibrate the telescope using the sun and also shows several measurements made. We note that the same procedures could also likely be done with the RTL-SDR.
A few days ago we posted about how Domi aka Domonkos Tomcsányi wrote on his blog about decoding and decrypting GSM signals from your own cell phones. Domi also did a talk at the CampZero conference which has now been uploaded to YouTube. His slides can be obtained from this link.
Marc Higginson-Rollins of the University of Kentucky has published an academic styled paper in conjuction with Dr. Alan E.E. Rogers of the MIT Haystack Observatory showing how they used an RTL-SDR to implement a Small Radio Telescope (SRT).
In the paper they discuss how they dealt with the frequency drifting and offset problems common in the RTL-SDR. They also show how they dealt with the center spur by correcting the bias that it introduced and how they filtered out RFI noise from a nearby radar station and electronics.
Using the RTL-SDR and SRT they were able to measure the spectra of several well known regions of neutral hydrogen emissions, and measure the galactic rotation curve shown below.
Wavesink Plus, the paid version of the trial version of Wavesink has been released on Google Play. Wavesink Plus is an Android app which has FM+RDS, DAB+ and DRM+ receiving and decoding capabilities when connected to an RTL-SDR dongle via a USB OTG cable.
We gave Wavesink Plus a test today on a HTC One X Android phone and were pleased to discover that it works perfectly. The user interface has been tidied up from previous versions, and DAB+ has been added. There is now also auto tuning functionality, which will automatically find a station.
In further testing we found that the latest version of Wavesink was fast and snappy and was able to load DAB+ stations quickly, and decode them with clear audio. FM radio also sounded clear and RDS information loaded quickly as well.
Download the trial version here and buy the full version from this link.
Rishi Patel has written on his blog about his radio astronomy project which involves an RTL-SDR and an impressive homemade horn antenna.
The horn antenna is constructed from cardboard foam and aluminium foil and is mounted on a telescopic mount. The horn then connects to a waveguide feed which is constructed out of a large metal can. The antennas waveguide then connects to a microstrip filter and LNA before finally connecting to an RTL-SDR. Rishi then uses a simple python program to gather the IQ samples from the RTL-SDR, and then draw the power spectral density plots.
With this setup Rishi was able to detect the Hydrogen line. Rishi also used a second even larger horn with a different design to plot the spectrum shown below of the Cygnus (red), Cassiopeia (green), and Cepheus (blue) constellations.
A while back we did a small write up on receiving and analyzing cellular GSM signals with the RTL-SDR. Now blogger Domi has taken it further and has done an excellent big write up on his blog showing how to receive, decode, and also decrypt your own cell phone GSM signals with the RTL-SDR.
Domi’s big write up is split into four posts. It starts with an introduction to GSM, then focuses on setting up the environment and required software, then uncovering the TMSI (step to be released later), and then finally shows how to actually receive and decrypt your cell phone data such as voice and SMS messages.
