Running WSPR on a Raspberry Pi 2

Image icon WSPR 3.9 running on Raspberry Pi 2169.34 KB
Image icon Decoded spots 299.26 KB
Image icon The little workhorse632.29 KB

After receiving a Raspberry Pi 2 from Element 14 Australia, the first thing I attempted was to compile and run WSPR 3.9 with a Signalink USB Soundcard (IC-7000 with a dipole converted from a broken G5RV). I followed the instructions of G4FRE ( except for an updated URL for the SVN repository (and using revision 2840 of the WSPR code). I will try to compile and run WSPR 4 later.

The Pi 2 consumes about 35% CPU while decoding spots (see attached screenshot of WSPR 3.8 for a sample of received spots) and takes anywhere between 10 and 15 seconds for a decode. I am pretty happy with the results of running WSPR for about an hour this evening. Pi 2 is running the latest Raspbian available as an image from the official website. uname -a shows the following -

Linux raspberrypi 3.18.7-v7+ #755 SMP PREEMPT Thu Feb 12 17:20:48 GMT 2015 armv7l GNU/Linux

For anyone attempting to compile WSPR, here are the steps I followed (except for one difference in the SVN repository location and code version, rest of the steps from G4FRE's blog post)

Run an update

sudo apt-get update

Install pre-requisites

sudo apt-get install build-essential subversion python2.7-dev python-numpy python-imaging-tk python-pmw libportaudio2 portaudio19-dev libsamplerate0-dev gfortran cl-fftw3 python-dev hamlib-utils

Grab revision 2840 of the WSPR source code

svn co svn:// -r2840

Configure WSPR

$ cd wspr
$./configure --with-portaudio-include-dir=/usr/include --with-portaudio-lib-dir=/usr/lib/arm-linux-gnueabihf

Force Hardware floating point processor to be used
Edit the Makefile with your favorite editor and ensure Line 5 reads as FFLAGS = -g -O2 -fno-range-check -ffixed-line-length-none -Wall -Wno-character-truncation -Wno-conversion -Wtabs -fPIC -mfloat-abi=hard and Line 9 reads as CFLAGS = -Wall -O0 -g -Wall -O0 -g -mfloat-abi=hard

Compile WSPR

$ sudo make

After compilation finishes (it took about 6 minutes on the Pi 2), you can run WSPR GUI with $ ./wspr

I connected the Signalink USB card to the Pi 2 after turning on my transceiver. aplay -l and arecord -l reported the Signalink in the list of playback and recording devices.

I am yet to try transmitting with the Pi 2, that is the next step. It is incredible to think about a $35 credit card sized capable of doing so much!

Update: Soon after I finished writing this post, I got the Pi 2 to key the transceiver and run a few WSPR cycles, first on 14Mhz and then on 10MHz.