SSTV beacon based on a Raspberry Pi

The Budapest hackerspace did some joint work with a local ham radio club and created an SSTV beacon housed inside a CCTV case that takes an image of its environment and transmits it using slow-scan television over ham bands.

As the title says, the build uses a Raspberry Pi to process the image taken from its camera and then transmits it over the air using a Ricofunk UHF transceiver with a main frequency of 433.425MHz. On the software side, PySSTV is used to convert images to frequency/time tuples, UNIXSSTV then creates the actual audio file and finally sox plays it. To avoid screwing up the Raspberry SD card, every part of the filsystem is either mounted in read-only mode (things like /home and /usr) or uses a ramdisk (things like /tmp and logs).

The plans, schematics and source code are available, so they hope that other hackerspaces will join the ranks!

Comments

  1. fartface says:

    Not really a new idea. SSTV beacons have been running on linux for over a decade.

    It’s just showing that the rasPi is still king for tinkering.

  2. Chris C. says:

    With a hangover and before coffee, first impression: “Why is there a saltine cracker on top of that Pi?”

  3. JackTheVendicator says:

    Since it’s on 433 MHz, could be used unlicensed inside the 25 KHz channels there?

    • Robert says:

      In my opinion you would be better off transmitting via the Ham bands as they tend to have more people listening for this kind of thing. Even if you don’t have a license you can still receive all you want.
      It makes me wish I had a HT that I could dedicate to being a transmitter for my pi.

  4. Strain Reliever says:

    The photo of this project shows an inexpensive “Cannon” connector. It is an important component that everyone should be familiar with.

    For those not aware, they can be purchased at most radio shacks. They are excellent! They are really heavy duty, with the locking collar that provides great strain relief. And they are Cheap! With some RTV they can be extremely weatherproof, but still fairly easily disassembled.

    Their availability at rat shack relates to their use as CB microphone cables.

    • DainBramage1991 says:

      Their use is not limited to CB. Many older and higher-end ham radios use them, as well as many commercial radios. They are a pretty standard connector for radio microphones. Typically, CB mics use the 4-pin version of the connector (the version you’ll find at Radio Shack), and other types of radios use other variants. I think the 8-pin version is most common, at least in my experience. My Icom and Kenwood radios all use them. These can be obtained through HRO (Ham Radio Outlet) and probably other sources.
      I’m not 100% certain, but I believe they are properly referred to as 1/2″ DIN connectors.

      • RunnerPack says:

        You can also find them on eBay as “aviation connectors”. I recently got 10 pairs of the 7-pin variety (for about US$1.13/pair) and used three of them to replace the 0.1″ headers used for axis motor connections on my MaxNC mill. It actually turned out quite slick-looking, and they’ll probably outlast the mill since I won’t be dis-/re-connecting them very often, if at all.

  5. eb4fbz says:

    Try easypal, it’s digital sstv, incredibly high quality.

  6. LA8IMA says:

    How does it handle ptt?

  7. Gerrit. says:

    You also can use the Raspberry Pi as transmitter, using PiFM.
    http://www.instructables.com/id/Raspberry-Pi-security-Slow-Scan-Television-Camera/

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 92,441 other followers