W SPR receiver with the Banana PI the ideal complement to the DDS WSPR transmitter
(Translated into English by: DL8CQ)
With the U02 DDS synthesizer a powerful WSPR TX is available that produces a superbly accurate WSPR signal due to direct digital synthesis. Of course you want not only to send but also to receive. For this small single-board Linux computers are an ideal solution.
As a first step the Banana-PI was converted into a powerful WSPR RX, together with a normal transceiver. In a later step, we will replace this transceiver by a self-made unit.
The following steps are basically valid for all Linux-based computers, i.e. not limited to the Banana PI. Prerequisite is an ARM Cortex A7 (or higher), with the NEON core mathematics, and preferably a dual-core processor.
The steps under Linux can be quite tricky, if no appropriate instruction is available. Therefore I did a number of trials to find the most efficient solution.
As best WSPR decoder finally the solution of K9AN was found. This C-Porting has over the stock K1JT software a few advantages in the decoding quality. But what is even more important, it needs only two additional software packages. In contrast, the K1JT software requires a huge number of additional libraries which are difficult or impossible to find or install.
The operating system:
Even though I am rather a friend of openSUSE, in this project working with Lubuntu was easiest. Here all the required software packages were easy to find and install.
Installation of the operating system, see HERE .
I have worked out two solutions, which will be described separately:
WSPR receiver as pure console solution without manual operation, fully automated operation.
WSPR receiver with comfortable user interface with ARM-Linux X-Windows.
Conclusion:
A small Linux minicomputer is all you need to receive WSPR spots. I recommend a dual-core computer as the Banana PI because always two processes must run the same time, the recording and the decoding.
To send WSPR spots we don't need this mini computer because we have a much better solution, which also contains the complete RF branch and requires no transceiver: the U02 DDS synthesizer .