GQRX and SDRPlay RSP1A

I’ve own a SDRPlay RSP1A SDR and since I use Linux I’ve never used SDRUno, just CubicSDR that works fine with the RSP1A.

Nevertheless one thing that annoys me on CubicSdr is that we can only pipe audio out from the application, while on GQRX we can pipe data out through UDP, and hence we can pipe it out to basically anywhere and not be dependent of the audio interface and audio routing on the local PC.

But the truth is that I never was able to make GQRX to work with SDRPlay. I’ve followed some tutorials around the net such as this: http://thomasns.io/gqrx.html and this http://dk3ml.de/2019/01/12/running-sdrplay-with-gqrx-on-ubuntu-18-10/ but at the end I always had this, even with the latest versions of GQRX that support SDRPlay:

GQRX SDRPlay

While I can hear the FM station at the above frequency the frequency panadapter has a hump at the middle and that’s it, not exactly what I was expecting.

Well the issue is that GQRX at startup does not setup SDRPlay RSP1A propertly and so it shows the above behavior.

So if we get the initial GQRX settings for the SDRPlay:

SDRPlay Settings

it looks fine, but as we’ve seen the end result is not as expected. So what we need to do is to re-enter the settings again in a certain order to make this work:

  1. Stop the data capture, without exiting GQRX (press the Play button)
  2. Edit the Device settings and choose any other than SDRPlay, and then choose again SDRPlay again. Make sure Bandwidth is set to 0.6Mhz.
  3. DEfault SDRPlay Settings
  4. As we can see the default Input rate is set to 2MBps.
  5. Press Apply, and if we start the capture it should work now, but we have a RSP1A,so…
  6. Open up again the settings and change the Input Rate to the maximum that RSP1A supports: 10MBps

The end result is this:

Proper SDRPlay on GQRX

And now it works as it should.

Conclusion:
While a bit annoying it’s good to see GQRX working fine with SDRPlay RSP1A. Still through GQRX we can’t control the FM and DAB notch filters, which CubicSDR can.

CubicSDR and Arch Linux (Again…)

Again quick note if installing CubicSDR in Arch Linux:

Arch Linux LiquidDSP package current version on the repository is 1.3.2.

Using this version of liquiddsp or liquiddsp-git breaks CubicSDR compilation, and hence if installing CubicSDR from AUR fails:

cannot convert ‘double’ to ‘liquid_ampmodem_type’

The solution to solve this issue is to use the package manager to remove the offending 1.3.2 version and manually install the 1.3.1 version, and then also install manually the CubicSDR according to the CubicSDR install instructions..

Not ideal, but it will get things done.

Simple instructions:

pacman -R liquiddsp liquiddsp-git
mkdir liquid
cd liquid
wget https://github.com/jgaeddert/liquid-dsp/archive/v1.3.1.tar.gz
tar xvzf v1.3.1.tar.gz
cd liquid-dsp-1.3.1/
./bootstrap.sh
make -j4
sudo make install
sudo ldconfig

Until CubicSDR upgrades to use LiquidDSP version 1.3.2, this is the interim solution.

SDRPlay, CubicSDR on Arch Linux

This is just a simple post for writing the instructions for installing and using SDRPlay RSP1A (Should work for other versions) and CubicSDR on Arch Linux. I’ve previously installed most of the supporting software manually on my PC, and also had trouble installing the SDRPlay driver on Arch Linux with the SDRPlay installer on my PC. Since I have a lot of QRM (Noise) in my home, the next step was to use a portable computer to move the SDRPlay outside.

So, the following instructions are much more streamlined, since all the required software is on the AUR repositories, and so no “hacking” is needed.

Installing yay AUR package manager
If necessary we should install a AUR package manager. There are several ones, but as far as I’m aware, for now the yay is the currently maintained AUR package manager:

git clone https://aur.archlinux.org/yay.git
cd yay
makepkg -si

We can now use yay.

Installing CubicSDR with SDRPlay support:
If before installing CubicSDR we install HamLib support we will have a new menu on CubicSDR for rig control, otherwise it wont appear.
Then we need to install the SDRPlay driver, Soapy support and also CubicSDR.

yay -S hamlib
yay -S libsdrplay
yay -S soapysdr-git
yay -S soapysdrplay-git
yay -S soapyremote-git
yay -S soapyrtlsdr-git
yay -S cubicsdr-git

I’ve also added support for remote devices and the ubiquitous RTLSDR dongles.
CubicSDR will take a while (20 minutes, it will depend how fast is your computer) to compile, mainly because of the wxgtk widgets.

After it ends just connect the SDRPlay to the computer USB port, and execute CubicSDR. If the SdrPlay does not appear on the device list, press the Refresh button:

And that’s it, no fuss install, at least for me.