Home of Student Hobby Electronics. Inspired by a talk on Software Defined Radio (SDR) during a TinkerSoc night, and motivated by the rocketing number of hits the society’s website after their blog post about SDR was featured on Hack-A-Day.
I decided to try it out for myself! SDR works due to the RTL2832 chipset which has a very wide frequency receiver range. This chipset is used in a lot of the USB TV tuners out there, however not all of them. A list has been compiled on the Osmocom.org website where they also have a huge amount of information about SDR. Having brought myself a USB TV Tuner off Amazon for £14 and free shipping it is clear that this is a really inexpensive way to get into amateur radio. The USB Tuner arrived at my house at university on the day of the fifth Raspberry Pi Jam, it seemed like an ideal opportunity to combine the two interests.
RTL-tcp is a sub program of RTL-sdr which is a command line interface program for controlling the TV tuner. To start with I checked that all dependencies were installed. A $40 Software-Defined Radio. The last time I ventured into the waters of software-defined radio (SDR) was seven years ago, when I reviewed Matt Ettus’s Universal Software Radio Peripheral.
While it’s an excellent product, the basic motherboard at the time cost US $550; daughterboards for different frequency ranges cost $75 to $275 [see “Hardware for Your Software Radio,” IEEE Spectrum, October 2006]. And I spent more than a few frustrating hours compiling the needed software on my MacBook Pro. This time I was able to get my feet wet for about $40—and the software took about 2 minutes to download, install, and run. This minor miracle was made possible by Finnish engineering student and Linux developer Antti Palosaari. Digital radio enthusiasts immediately began adapting open-source tools that can translate I/Q information into audio and data streams. Different receiver dongles pair the RTL2832U with different radio tuners, so the exact range of frequencies that can be received varies.
Raspberry Pi as Remote Server for RTL2832u SDR. Introduction Note: Since this project was posted it has been brought to our attention that RTL2832U / R820T sticks may not be fully supported in the RTL drivers used here.
The RTL2832U / E4000 sticks work fine. One of the often overlooked features of the RTL drivers for the RTL2832U SDR sticks is the TCP server. The TCP server allows you to send data from the RTL2832U stick across your home network to a remote PC running a program to process the data back into SDR information such as SDR Sharp. While the Raspberry Pi is not quite powerful enough to run current programs to decode and process the SDR data from the RTL2832U stick, it can do a very good job of running the rtl_tcp server. This means that you can plug the RTL2832U stick directly into the Raspberry Pi and wind up with a very small and portable SDR radio server.
Demonstration Video Why would you want to do this? There are several reasons you might want to do this. 1. 2. 3. 4. 5. 6. Geting it Going 1. 3. 4. Potential Problems.