Monday, October 23, 2017

Run your own Web SDR with OpenWebRX on Raspberry Pi

There's quite a few excellent remote receivers running WebSDR but unfortunately the author has decided only to give the software to agree to make their server publicly available. I think it's a pity that this software is not available for people wanting to share their home receiver with, perhaps, a few friends. It's also a pity that this software isn't open source.

An alternative is the excellent OpenWebRX by András Retzler.

In the ARNSW home brew group we have a regular contact on 80 or 40m but often we can't hear each other due to local noise. It's been proposed that we place a remote receiver at a low noise location and all listen over the web. One idea is to have a fixed receiver simply stream the audio, another is to set up a web SDR. I'm investigating running this on a Raspberry Pi.


The software is available from GitHub here.

There's a few dependencies summarised here:


  • git clone https://github.com/simonyiszk/csdr.git
  • sudo apt install rtl-sdr
  • sudo apt install libfftw3-dev
  • sudo apt install libusb-1.0-0-dev
  • sudo apt install cmake


Everything is in the readme to build and install, I did little except follow the instructions and install missing things as they came up. Let me know if you're stuck.

Because I'm currently running an RTL-SDR in direct sampling mode I had to build a fork of rtl-sdr that supports this.

OpenWebRX is a terrific piece of software, easy to build and run, and I want to thank Andras for his contribution. If you do have a fast internet upload and a permanent receiver you can add yours to the list.

Update

The RTL-SDR doesn't work very well on HF like this so I've now switched to using a HackRF One that's working quite nicely.


The AGC is rather savage but it's good to listen to overall.

4 comments:

Cale M. said...

The WebSDR author must get that request constantly. I've also emailed him asking if he had a "personal use" version of the software. No dice. Fortunately, OpenWebRX is becoming a much better alternative.

powernumpty said...

In defence of WebSDR I requested the code a few years back but when I realised the sound card I purchased for the Softrock (192kHz under Windows) had drivers limited to 48kHz on linux and the spare PC I considered using would be eating 95 Watts for 48kHz of HF I gave up,(this was a good few years back). If he had too many like me it must be frutrating to waste emails, I honestly did start with good intentions.
These days with PI's and KiwiSDR I'll stick with OpenWebRX. Back then I didn't have the kit but did have decent noise levels, now I have the kit and high noise (QRM).
Stu

Unknown said...

It these actually work decently on HF. I've got a couple of Kiwis and SDRplay and they're not that good (The kiwis are especially nice) and their bandwidth is pretty small, but it's easy to overcome that with multiple profiles ( "40 low, 40 high" etc.).

The new version of OpenwebRX supported by Jakob, is particularly nice with its digital decoders, etc.

Giotis said...

Hi, I am trying to use the Openwebrx with a Raspberry and Hackrf One but I have problem on the gain settings. I have an external LNA that need the power supply from the Hackrf but I am not able to find the parameter that enable it.

Are you so kind to post your config_openwebrx file so I can start from your values?

Thank you and congratulations for your blog pages, you are always one of my source of inspiration for new projects