In the last month, I worked over the optimization of my remote radio station. I have a Yaesu FT897D in my parents QTH in a wonderful open position and I would like from my house in city.
It was not a big problem to setup a remote station using a notebook running the HRD server and controlling the radio via CAT. I had some minor problem in obtaining the best voice modulation using the notebook soundcard. I’m working on it and I hope to solve it quickly. For the voice connection actually I use a classical skype connection. Everything is working quite well despite the frequent crashes of HRD, probably due to the low bandwidth of my parents QTH.
Furthermore I would like to save a notebook only for this activities so I started investigating on Rpi and its implementation. As many of you know in the raspbian distribution there are already the hamlib library and various tool for CAT control (see hamlib net control) . The Yaesu FT897 is poorly implemented but there is the possibility to improve the basic controls.
The other brick completing the set is the Wolfson Audio Card for Raspberry: it is a powerful low cost soundcard that can be fitted on raspberry giving the possibility to a) recording audio and b) using some nice DSP voice feature. The drivers for this card are going to be integrated in the latest version of raspbian kernel distribution, but it is possible to do a lot already with the 3.10 kernel (follow this user guide for installing it).
For the audio part I’m going to use the VoIP smartphone software linphonec that is compatible with wolfson audio card (doing some hacking for downsampling to 8kbit the streaming).
I also verified the the Kernel 3.10 support the USB-CAT cable based on my Prolific 2303 chipset.
Actually I have all the pieces of the puzzle in my hand and I’ll update this post as soon with details trying to provide a step-by-step tutorial.
PS: I was thinking to name this project
RASPAM “rasp-ham-remote” but I open to suggestion 🙂
UPDATE (Dec 29, 2014): Thanks to Giovanni Moretti ZL2GX from New Zeland for name suggestion that for the moment sounds an improvement for the project name. About the Wolfson Audio Card: I think that the support from the producers is still unsufficient. I’m following the GITHub contribution from wolfsonmicro stuff and the last activity was one month ago.