Find all your DIY electronics in the MakerShed. 3D Printing, Kits, Arduino, Raspberry Pi, Books & more!
web_sdr_graphic.jpg
web_sdr.jpg

Ham radio enthusiast PA3FWM constructed this impressive software defined radio, which is capable of capturing nine amateur radio bands (VLF, LF, MF, 160m, 80m, 40m, 30m, 20m, 15m) simultaneously. The system comes complete with a web-based interface that lets you control which band you would like to listen in on. The image that you see above (click for a higher-res version) shows a waterfall graph for each of the radio bands. Active transmissions show up as vertical white stripes, and you can move a small yellow filter to change the frequency that you want to listen to.

There is actually a whole community of people who run stations like this, which you can find at websdr.org. If you’re interested in amateur radio but don’t have one of your own yet, or would like to see what’s happening in other parts of the world, this could be a really fun system to play with!


Related

Comments

  1. mpechner says:

    I am a ham radio operator, call sign NE6RD. Living in a condo I have 3 ways to get my radio fix. First is I have access to a remote station W7DXX using client software to control the radio and skype for audio. Second is to load my radio and gear in the car and setup picnic portable. Third is web available software defined radios.

    The websdr radios are fun. They are located around the world, so you can listen in on the ham radio activities from radio around the world. I wonderful way to listen in on the world.

    For those who think it is archane, use a websdr to find a pile up on the weekend when a content is going on. A pile up is when someone is calling for others to contact them, calling CQ CQ. Then for what ever reason, dozens of people wait to contact that person. Sometimes the reason is that someone traveled to somewhere unique, maybe some atoll in the pacific that no one has operated from before, or maybe not in the last decade or so. People want to say they talked to that person, it is called getting in the logs.

    If you listen to a pile up, try to write down the call signs you hear. See if you clearly hear the one the calling operator chooses. You develop really great listening skills.

    What can I say. I am nerd who loves nerdy hobbies.

    1. Matt Mets says:

      Oh, that’s awesome! I’m still pretty amazed that this can work- I guess I need to go learn about bandwidth again.

  2. capt.tagon says:

    Ham radio has finally moved onto the next dimension. Being able to monitor all bands, find the activity and tune in. I’ve got to get some software up to do some signal decoding. 73

  3. Marcel says:

    Looking at the multiple bands like that makes me ask ‘does anybody use multiple bands for data transmission?’ — parallel send and receive if you catch my drift.

    (Are you permitted to send data over these bands?)

    [m]

    1. Alan says:

      One of the many great things about ham radio is that it’s an open frontier for experimentation. The FCC and its sister agencies in other countries place relatively few restrictions on amateur emission types, and even fewer on hardware or software designs. As long as you keep it inside the ham radio bands (no interfering with nearby commercial or military users, for example), and follow a few simple guidelines, it’s all good.

      High-frequency data modes are the fastest-evolving technology on the ham bands right now, with many folks around the world developing very clever solutions to the medium’s inherently narrow bandwidth.

    2. mpechner says:

      When talking to satellites and ISS, the send and receive are on different bands. So this is already done.

      I have never heard of anyone sending the same signal on the same bands simultaneously. Receiving a swath of signal and decoding it all is easier than having to send multiple discrete signals at once. It can be done sequentially. But simultaneous transmissions, means controlling multiple transmitters almost everyone with their own antenna.

      Keep in mind that ham radio assumes you transmit not broadcast. Meaning there is supposed to be someone on the other side. Or you are looking for someone to answer, calling CQ. http://www.eham.net/articles/7952

      This is different than CB, where some people broadcast, talked with not assumed audience.

      There are band plans and gentleman’s agreements where different modes are done.

      For instance, the US band plan showing the generic data/voice split is here: http://www.arrl.org/files/file/Hambands_color.pdf But if you are interested in PSK31, then a search gives you: http://k0swi.microlnk.com/LISTS/PSK31/PSK31%20FREQUENCIES.htm which is what all amateur operators agree to world wide.

      And if you want to do cross band, send on band and re-transmit on another. ex. transmit voice on 144.510Mhz and have something just hear it and retransmit on 446.100Mhz you need to read part 97 of the FCC rules. http://www.arrl.org/files/file/Part97_SinglePage.pdf This is different from the satellite where you ask on one frequency and get a response on another.

      You have the freedom to play. But you have to know the rules. This is why there are the 3 levels of amateur radio tests to takes. None of which require any morse code in the US anymore. A significant port of the test isn’t just electronics, but safety, part 97 rules, can common operating procedures.

      They once you get your license you can get a cool call sign like mine. NE6RD :D

In the Maker Shed