Back from Dayton! (And a Raspberry Pi update)


I’ve just returned from this year’s Dayton Hamvention, and met up with some folks from Virginia Tech who are successfully using the FCD+ with the Raspberry Pi. Briefly, they are using their RPi’s to allow remote reception from LF to 2GHz. They’re using a recent Raspian Wheezy image together with some code to stream the full 192kHz span over UDP (I guess similar to the code that I wrote recently for OpenWRT & the FCD+ together with GnuRadio), plus a version of Alex Csete’s FCDCTL to remotely set the frequency.

Once I have more details I’ll post a how-to here. I’ve long been convinced that the RPi and the FCD/FCD+ are perfectly do-able, but I had difficulties with earlier Raspian Wheezy releases and its USB stack as well as the use of Qt to control the FCD/FCD+ on the RPi, so I’d been waiting for a more stable software platform which it looks like we now have.

The FCD+ stock is still good so follow this link about ordering details, or to order right now here’s a direct link straight to the shopping cart.

Many thanks, Howard

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9 Responses to Back from Dayton! (And a Raspberry Pi update)

  1. Stefan Wagener says:

    Hi Howard,

    Glad you came. Was great talking to you.

    73, Stefan VE4NSA

    • admin says:

      Hello Stefan

      You too, I will see if I can get hold of some technical diagrams for the satellite for you!

      Many thanks, Howard

  2. Ricardo EA1APM says:

    This is so interesting. I would like to install my FCD and Rpi in a waterproof cabinet in my roof, with a short coax run to the antenna, and then UTP to the shack. I always thought it was a matter of time to make it work so I’m glad to see it is possible now. I’m eager to learn more.

  3. Ken, N4AI says:

    Sure was a pleasure shaking your hand at Dayton Howard.

    Thanks for making the exchange for me.

    Sounds exciting about the RPi.

    Hope to see you again soon.


    • admin says:

      Hello Ken

      You too: I have a handful of units here that need looking at, I’ll be looking at them this week.

      Many thanks, Howard

  4. Tony Abbey says:

    Hi Howard

    Great news about the RPi – us in the Radio Astronomy community have been waiting for this for some time – I had been putting such usage on hold with my insufficient Linux knowledge to get down to understanding the basic incompatibility which was causing multiple frequency writes to the FCD to eventually freeze, preventing using it for spectrum analyser-like scanning with the Pi. On a different issue, have you been following the plots Jim LeSurf put on the FCDPP Yahoo Group showing the strangely different noise floor from the I and Q outputs? I’m not sure whether there are too many newbie questions on that group now for you to follow the more interesting technical discussions.


    • admin says:

      Hello Tony

      I’ll take a look at those comments: it’s been pretty busy over the past few weeks, but RPi is on my list to document.

      The Yahoo groups on the FCD/FCDPP are a welcome independent community, and as well as the Yahoo groups, I receive many questions from a number of sources, and it’s quite hard just keeping up with those for one person as you can imagine! The huge benefit of the Yahoo groups are that typically the breadth of end user experience is far greater than mine alone, so it is very much appreciated.

      Many thanks, Howard

  5. Jan, ON7UX says:

    An example of working FCD+ with Raspberry Pi is discussed by Alex, OZ7AEC.

    • admin says:

      Hello Jan

      Many thanks, I was aware of that, although there is some description of the device hanging. I believe that since Alex’s note there has been a lot of work done on the RPi’s USB stack which has generally been acknowledged to need some work. As I understand that most of the USB host stack is implemented inside the GPU, it’s not been open for Joe average to debug.

      Many thanks, Howard