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(Short-, Medium-, Long)wave Radio Meets Digital Stereo

Posted by timothy on from the use-tubes-they're-smoother dept.

cryptec writes "Today shortwave radio will have some new life pumped into it as the German broadcaster Deutsche Welle will be the first full time shortwave broadcaster of DRM (Digital Radio Mondiale). DRM is a full stereo fully digital broadcast system. The quality of the broadcasts are close to that of FM radio. For samples check out this link." Akai adds this link to an article in the San Francisco Chronicle with some more information, like the involvement of the BBC and Voice of America in this undertaking.

18 of 194 comments (clear)

  1. Nice! by meringuoid · · Score: 4, Interesting
    Well, it sounds nice, over the web... Of course, that's before the /. effect strikes :-)

    Digital radio over SW sounds interesting. I wonder if old Auntie's going to pick this one up? I gather BBC services got cut over North America recently in favour of web broadcasts... maybe digital technology will allow that to be reinstated in the future?

    --
    Real Daleks don't climb stairs - they level the building.
  2. ham radio by tadheckaman · · Score: 2, Interesting

    amatuer radio might be able to use this, since they dont need a boat load of bandwidth, only a tiny bit. They allready have VHF and UHF digital radios, too, so I dont see why it wouldnt work on HF.

    --
    My potato gun was confiscated by the United Nations. They said I wasn't allowed to have weapons of mash destruction.
    1. Re:ham radio by Beryllium+Sphere(tm) · · Score: 3, Interesting

      At first glance it looks like the big win would be using the error correction protocols to get through noise and cope with hostile ionospheric conditions.

      "The RF bandwidth can be chosen between 4.5,5, 9, 10, 18 and 20 kHz", according to an article at drm.org. Ham voice transmissions already fit inside 3KHz.

      There's also a bucket of features which are great for broadcast, like redirect pointers to better frequencies, which are irrelevant bloat in the ham world.

  3. yet another avenue for Peer to Peer by victorvodka · · Score: 5, Interesting

    Say what you want to about the utility of digital music over short-wave, I think it's a fascinating development. It's just another big application of Peer to Peer technology, one completely bypasses the internet. It's not just music that can be broadcasted this way - files can be sent and they could contain anything - newspapers, video, software, worms - and they could come from anyone with enough power to broadcast them. If the use of such technology becomes widespread enough - look for this becoming just another way to suck data into your computer, no matter how isolated you happen to be.

    --

    The flag just makes more sense than the constitution. - Judas Gutenberg

  4. Isn't going to fly by ferreth · · Score: 3, Interesting

    'Ya know, I used to think short wave radio was cool - until I discovered internet broadcast. Now I can listen to stations around the world, without buying any extra gear.

    Maybe in the 3rd world, oh wait, the gear is going to be more expensive than SW radio - maybe not there either. Who is going to buy this to get the mass market price down? Not me.

    --

    W9x:Thanks for the make-work project Bill.

  5. Re:Redundancy for satellites... by ColaMan · · Score: 2, Interesting

    There's a commercial packet radio system around for long-distance trucking fleets that uses the meteor trail to do just that. It listens for a signal from home base then quickly sends a packet or two back. Good for digital store-and-forward of truck info etc.

    Maybe it was on slashdot? was a year or two ago now tho'

    --

    You are in a twisty maze of processor lines, all alike.
    There is a lot of hype here.
  6. Re:but then ... by Anonymous Coward · · Score: 2, Interesting

    Seems like some people still want to listen on shortwave.

  7. Not so special by poptones · · Score: 4, Interesting

    A receiver with a wideband IF output (ie just about any ham receiver), a PC, and a soundcard. That ain't so special; some of you need to free your minds, much less free your radios.

    1. Re:Not so special by wowbagger · · Score: 2, Interesting

      Not quite - the IF out on most ham rigs is 10.7 MHz. You are going to have a problem sampling that with your soundcard, as your soundcard's inputs will filter that right out.

      You'd need to bring that down with another mixer to below about 20 kHz so that the filters on the soundcard won't trash it, or you would have to bypass the filters on your soundcard and subsample it.

      --
      www.eFax.com are spammers
    2. Re:Not so special by poptones · · Score: 2, Interesting

      Not exactly. By "wideband" I mean post I-F but before audio filtering. This is fairly common even on those "world radio" sets you buy at consumer goods stores (I want to say wal-mart but I'm not sure if wallyworld has one. I'm confident, however, radio shack has more than one model like this). The "wideband" output will be something like 100-100khz instead of 100-10khz, and this can be sampled by a soundcard. back when FM stereo was new many FM radios were retrofitted just this way: take the IF output and run it into an external decoder. Only now a PC with a cheapo soundcard and can handle the bandwidth of an HF transmission.

    3. Re:Not so special by pe1rxq · · Score: 2, Interesting

      Wideband outputs are totally useless for drm.
      These outputs are past the demodulater, so you get a unfiltered basenband signal.
      You need a IF signal as that still has the properties of the RF signal. Most smallband FM rigs or AM rigs have a second IF of 455 or 473 Khz which can be mixed down to 12Khz rather easily. This can then be sampled with an audio card.

      Jeroen

      --
      Secure messaging: http://quickmsg.vreeken.net/
  8. Software defined radio! by tweakt · · Score: 3, Interesting
    This is a perfect application for Software-Defined Radio... see GNURadio.

    It's already been used to decode HDTV signals.

    Slashdot also covered this technology a couple years ago.

    1. Re:Software defined radio! by wowbagger · · Score: 2, Interesting

      I am well aware of GnuRadio - in fact, if you look at the FAQ, you will see I am quoted in it.

      Also, I do Software Defined Radio for a living.

      However, the point of my previous message is that the average person with the average receiver is not going to be able to receive this signal.

      --
      www.eFax.com are spammers
  9. Citizen's bandits by poptones · · Score: 4, Interesting
    Actually, it's never occurred to me until now that this same technique could (as another person here suggested) be applied to p2p communications. The FCC pretty much abandoned 11 metres long ago; there are several folks around here who still dabble in CB and not one of them is strictly "legal" - sliders, amplifiers, and even FM gear are all the norm on the band. It's awash in noise and crap but might actually be usable if some modern DSP methods were applied to communications. And, because it is (unofficially) unregulated, there is an opportunity for pretty much anyone with a CB and a PC with a soundcard to get involved.

    In an area where 802. gear is pretty much useless because of line of sight issues, this might be just the ticket. There is more bandwidth in an HF carrier than in a phone line, and using low cost DSP tx/rx front ends it would even be possible to utilize two or three channels at once.

    Hmmmm.... I think I need to go visit the neighbor.

  10. I like it! by zakezuke · · Score: 2, Interesting

    There are those who would be critical of such things, but I like it! Ham radio to broadcast digital media will open a new door to... dare I say it, multi-casting! Why bother broadcasting on the net when you can actually recieve digital media over shortwave / ham and not have it suck up your bandwidth. Took us long enough to converge these two technologies.

    Bit-torrent is a pretty cool and hip standard in it self, but imagine releases sent digitaly via the airwaves, using a simple 50ft long wire that can reach between seattle and finland. Not perfect mind you, even the best sets are going to have some unrecoverable packet loss, but hey. Not exactly ideal for let's say a linux distro, but through the use of checksums I can see how such a broadcast service could get you most of what you need, and anything that fails you can just download via standard means.

    And as a bonus... to people who have a broadcast license, could open the door to ham based ISPs. While a dated technology, short wave / long wave is a proven one. While i'm sure statalight would no doubt be superior, land based access would be cheeper to deploy, and can even be based on older tube technology.

    This is something i'd use, even if just to get music from overseas.

    --
    There is no sanctuary. There is no sanctuary. SHUT UP! There is no shut up. There is no shut up.
  11. Acronyms by Luke-Jr · · Score: 2, Interesting

    This is the 3rd definition of DRM now...
    1. Digital Restrictions Management (M$)
    2. Direct Rendering M(anagement?) (XFree)

    --
    Luke-Jr
  12. Re:Aww... by AndroSyn · · Score: 2, Interesting

    You realize that me, you and probably like 2 other people know who Welle:Erdball is, which is unfortunate because you've got to give a band credit that actually uses a C-64 as an instrument. Also, hell they've got a song called Bill Gates Komm' Fick Mitt Mir(translates out to "Bill Gates Come Fuck with me").

  13. Ten-Tec's RX-320D is a DRM-enabled receiver by Anonymous Coward · · Score: 1, Interesting

    See:

    http://www.tentec.com/Amateur.htm

    for a relatively inexpensive DRM-enable receiver...

    however, you will need to purchase a binary-only, proprietary decoder in order to receive DRM... this is an insidious enticement...

    i have the 'plain' rx-320, which works well with Linux, and is a wonderful broadcast AM and shortwave receiver... there are several Linux clients for the rx-320, and i ported the xclass libs and rx-320 client to NetBSD...

    the rx-320 is unlike other 'PC radios' in that it can run standalone after being programmed via its serial port... controlling the radio is via a basic set of seven controls, but you can use the controls to change frequencies, volume, line out, etc., along with implementing scanning, band sweeps, and of course, use its DSP for filtering received signals...

    DRM in shortwave is not a good idea unless an open-source solution for the decoding is implemented... fortunately there is at least one such project, and if digital shortwave takes off, there's hope for some free solutions...

    otherwise, you're going to pay, pay, pay! and don't expect a Linux version!

    i don't expect DRM to take off... too many countries don't have the money to change over the equipment, there are too many SW receivers out on the market, and a basic SW receiver can be manufactured and sold for less than US$10...

    one of the best 'deals' for SW receivers is the Sangean ATS-505 (also once sold by Radio Shack, and liquidated at $50)... you'll want a receiver that can also receive USB (upper sideband) all the SW bands, and has 1kHz tuning (many of the cheaper ones only offer a subset of the SW bands and 5kHz tuning)...

    detailed pics and specs on the rx-320 are here:

    http://www.tentec.com/TT320.htm

    p.s. some folks spend $2000+ on receivers, but you can get almost the same capabilities in a Yaesu FT-817 - and while you're at it, get your FCC license and become a ham operator - basic entry for Technician Class is a 35-question test (in the U.S.)... learn CW (carrier wave), aka Morse code, take another 35-question test and you'll be able to talk with folks around the world!