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Digital Signals Spark Static From AM Radio 176

Carl Bialik writes "Digital radio is touted as broadcast radio's golden ticket, but the transition to digital broadcasts is creating static and interference for many smaller AM stations that are still analog-only, the Wall Street Journal reports: 'The AM stations most affected are those whose neighboring stations -- nearby on the dial -- add a digital signal.' The WSJ adds, 'For some small AM operators, it adds insult to injury that the only company licensing the digital broadcast technology is one backed by the small stations' deep-pocketed competitors.' Critics question why the FCC only approved the technology from that big radio-backed company, Ibiquity."
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Digital Signals Spark Static From AM Radio

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  • by Alaren ( 682568 ) on Thursday March 02, 2006 @02:41PM (#14837057)

    "Critics question why the FCC only approved the technology from that big radio-backed company, Ibiquity."

    Silly critics. I don't think there's any question at all.

    • Sad part is that the same Azzhats (clear channel etc) will still own the bulk of the AM stations, The bulk of AM digital will be higher fidelity garbage, but it will still be garbage.

      There are a few good AM stations, but they are a small minority.
      • Sadly, co-channel interferance isn't something that is new.

        If you goto a larger city and scope the NTSC/DTV spectrum you will see interferance on every channel. A friend just did a large job in chicago and told me all about it. This in theory, wasn't supposed to be as a big of a problem as it is. The good news, DTV receivers handle it quite well and it's only temporary.

        All I can say to the AM folk...

        At least they didn't force the upgrades on you and force you to pay for their "work in progress" digital sig
  • by digitaldc ( 879047 ) * on Thursday March 02, 2006 @02:46PM (#14837103)
    The AM stations most affected are those whose neighboring stations -- nearby on the dial -- add a digital signal...Critics question why the FCC only approved the technology from that big radio-backed company, Ibiquity.

    Man, that Ibiquity seems to be all over the place these days.
  • by nietsch ( 112711 )
    Critics question why the FCC only approved the technology from that big radio-backed company, Ibiquity.
    What about: 'Because they payed the most money and the FCC does not mind creating monopolies when properly greased.'

    Once again, I am happy not to live over there, my middle of the road ideas would be considered ultra left wing in over there.

    • So, the FCC was happy to approve IBOC AM radio and not a competing technology, D-CAM but more than happy to let the market decide which digital cell phone standard should apply? If the broadcast standard a station wants to use does not cause adjacent channel interference why does the FCC care what technolog a station wants to use? In the case of IBOC, it does cause interference and shouldn't have been approved in the first place, but that's what happens when you have money and lobbyting power.
      • Who knows why the FCC really does things, but one can argue that broadcast bands should be limited in terms of modulation schemes because they serve the public at large over free airwaves, whereas cellular providers only serve their customers and often use purchased spectrum.

        Of course it probably would be better to let the market decide both issues.
  • Can someone explain why I need to by a $300 radio to listen to something that is not perceptibly different?

    At any rate it seems like another way to fleece the public.

    Anyway analog broadcasting should be preserved as they are easy to implment and use in the event of an emergency.
    • Re:Just like HDTV (Score:2, Informative)

      by SparkEE ( 954461 )
      So, that must mean you've never acutally watched HDTV signals on an HDTV set. If you had, there's no way you would think it is not perceptibly different.

      I currently have a tv with built-in HDTV tuner and a plain-old VHF antenna. I also have cable from comcast. Whenever I can, I watch over-the-air HDTV instead of the cable (which I'm paying for) just because the quality is so much better.

      (Why do I pay for cable then? 2 reasons, bundled with internet service, it's pretty cheap, and I get more statio
      • I'm fascinated by your comments because my views are similar to the grand parent.

        So you have killer OTA HDTV.

        But I don't see what's so *great* about having more when it generally means a plethora of re-runs, mundane cooking shows, and an automatic nipple of crap for kids to suck on.

        Is it the whole watercooler, "Did you see show XYZ last night?" thing?

        I pay $40/month for vaguely improved internet connection. If you put the difference between my 40/month bill and your total cable bill in the bank at the end
        • Without directly answering your questions (I'm not the OP), I have a few questions for you:

          1. Instead of buying CDs, buying MP3s, or even downloading music illegally, do you choose to tape your music on audio cassettes off of AM broadcasts?

          2. Assuming the type of music you like is never played on the radio, do you get your music by hand-recording live shows on cassette tapes?

          3. Do you prefer the sound of music on record players, because the natural filters and background scratch are how "music is supposed t
        • Now, to more directly answer your question, I find that I'm actually watching a few new-to-air series this year, which I find quite enjoyable:

          Lost
          Battlestar Galactica
          Drawn Together
          Rollergirls
          Monk

          Perhaps I'm wasting all my time doing this. Perhaps. But for the first time in 4-5 years I'm not playing an MMORPG or indeed any PC games (except ones released more than 20 years ago). Maybe watching TV is less stimulating for my brain, but then again I used my "free time" last night while watching TV to research
          • FYI, Monk is several years old now. It's been bounced around various networks, which gives it the appearance of being new.

            Good luck on your changes to planning/zoning ordinances.
            • FYI, Monk is several years old now. It's been bounced around various networks, which gives it the appearance of being new.

              I meant "new" in that there are new episodes airing. I don't actually watch it "new new", because it is on at the same time as Battlestar Galactica, and my DVR only has one tuner. I just recorded all the episodes on USA's New Year's Day marathon, and finished watching them last night.

              Good luck on your changes to planning/zoning ordinances.

              Thanks. Of course being on the city planning a
    • Re:Just like HDTV (Score:3, Informative)

      by westlake ( 615356 )
      Can someone explain why I need to by a $300 radio to listen to something that is not perceptibly different? analog broadcasting should be preserved as they are easy to implment and use in the event of an emergency.

      IBOC (In Band On Channel) is both an analog and digital service. no changes in frequency, no adapters required for older radios.

      It is efficient and higher quality and still free to the user, which is why even the shortwave broadcast bands are going digital.

      It is in Ibiquity's interest to enco

      • enhancements such as pro-logic surround sound.

        Two points I would like to make about this.

        First, Pro-Logic surround sound is a matrix system. It can be implemented wherever there are two separate channels of audio. Implement discrete surround and I will be impressed.

        Second, once you have implemented it, what are you going to use for source material? Music, in general, is two-channel stereo. New recordings could be made in discrete surround, but what about the very large corpus of existing work?

  • to listen to AM radio, usually the morning shows are the Howard Sterns & I'm rushing to get to work. Now PM radio tends to be more informative.
  • by Anonymous Coward
    My TV was so old that when I added a DVD player, the power button on the DVD remote also sent an "8" signal to the TV, thereby changing the channel. The company that made the TV had already been out of business for at least 10 years when I got the DVD player. I guess they never anticipated someone would have a clash of technologies more than two decades apart.

    Oddly enough, I have one of those "emergency" flashlights that would also change the channels on yet another ancient TV.

    And in yet another case, we ha

    • My parents flipped out after they built their new house because the fireplace would suddenly come on when they weren't home. Turns out the neighbor's garage door opener was the same frequency/channel as the remote to the gas fireplace.
      • A remote control for a fire? Now that's lazy.
        • Actually, it's super common in new houses these days, and the whole thing makes a lot of sense. Since the fireplace is gas instead of wood-burning, there's just an IR sensor that turns on the gas. The fireplace can be sealed too (glass or whatever), instead of open to the room. Plus, there's no chimney all the way to the top of the house, only a vent that goes directly out the back of the fireplace to the outside.

          I almost defy you to show me a house $200k around here that doesn't have one. Plus, this is
          • Actually, it's super common in new houses these days

            Just because it's common doesn't mean it's not lazy.

            Since the fireplace is gas instead of wood-burning, there's just an IR sensor that turns on the gas.

            See, lazy. You don't even have to chop and haul wood. What's the point? You don't get the wonderful smells of burning wood. You don't get a nice bed of coals for roasting marshmallows. You don't even get the satisfaction of starting a fire yourself. Starting the fire is more than half the fun of having
  • This will be a tough call for some of you. Lots of small AM radio stations are Christian stations. Prejudice against big business or prejudice against religion -- which prejudice will win?

    • Neither. Lots of small AM radio stations are Progressive/Liberal news/talk, like Air America [airamericaradio.com]. Can't imagine why Big Media would want them silenced.
    • I was going to object to the wording "prejudice against religion or big business". but it really made me think...

      I'm also prejudice against evil, greed, hate, ignorance, murder, stealing, corruption and encouraging child-molestation through practices like abstinence and denial.

      I suppose if you are not prejudiced against the latter group, you are quite likely to embrace the former.

      Thanks, this really helped me understand some stuff. Mod the parent up!
    • This will be a tough call for some of you. Lots of small AM radio stations are Christian stations. Prejudice against big business or prejudice against religion -- which prejudice will win?

      How about prejudice against misuing the public radio frequencies?

      I couldn't care less if it's Christian programming being stomped on, or Howard Stern. Of it Howard Stern was getting stomped on by Christian programming.

      They should bloody well keep the radio waves working correctly without spilling over onto other frequenci

      • The FCC requires stations not to interfere with each other outside of their core broadcast areas. The article complains about an HD Radio station interfering with a non-HD Radio station in an area which is outside the non-HD Radio station's core broadcast area.
  • A simple 4 step process:
    1. Buy radio station neighbouring a competitor's band.
    2. Broadcast FCC legal digital interference.
    3. ???
    4. Profit!

    Major lawsuits coming? Anyone?
  • by sweet 'n sour ( 595166 ) on Thursday March 02, 2006 @03:02PM (#14837250)
    I recently purchased a car stereo with digital support and can say that the AM digital stuff sounds absolutely terrible! You really hear the digital artifacts... tinny, cellphone-ish sounds. Also, the analog signals aren't in sync with the digital ones so that when the stereo goes from one to the other, you either miss something, or hear the same thing over again... typically around 4 seconds worth. Get into an area where the AM signal isn't too great, and the stereo repeately goes back and forth between analog to digital. It's enough to drive you insane.

    Hopefully digital AM will get dropped as people realize how terrible it sounds.

    FM, on the other hand, sounds great and doesn't have the sync problem.

    If I can only figure out how to turn off the digital AM support in my stereo!!!

    In case this is just a fluke, here are the details:
    AM 740 in San Francisco.
    Headunit: Kenwood KDC-890
    Digital Box: Kenwood KTC-HR100

  • by Anonymous Coward
    I am a broadcast engineer.

    This "HD Radio" is actually called IBOC (in-band, on-channel). Radio works by changing the amplitude (AM) or the frequency (FM). You're only permitted to change it by a certain amount--your bandwidth--otherwise it will interfere with adjacent stations. By adding more information, the digital data stream, you're using increased bandwidth.

    The other big issue with AM is overnight. Most AMs power down or sign off at sunset because the atomosphere changes overnight and AM travels mu
  • by dhickman ( 958529 ) on Thursday March 02, 2006 @03:19PM (#14837377)
    I love it, another untested closed standard.

    The AM MW mode should be left alone. The band that it is used in the US is not that reliable for digital modes, but it is very reliable for AM transmision to local areas.

    This band/mode is essential for emergencies. Everyone in the US has an "AM" radio somewhere in the house or their car. It will just work.

    Has the FCC rated this HD radio as an actual mode?

    I have started to experiment with drm on my HF equipment and in fact i am upgrading to a SDR-1000 in a month or so.

    With my existing equipment, I have heard a few of the DRM broadcasts on HF Shortwave and they are impressive. I have heard that you can broadcast it with a SDR-1000.

    DRM is an open standard based on mpeg4. In fact this is the standard for european countries. There is GPL code for both listening and transmitting it.

    http://en.wikipedia.org/wiki/Digital_Radio_Mondial e [wikipedia.org]

    KB0FHF
  • Ah, those Yankees (Score:2, Insightful)

    by rueger ( 210566 )
    It's worth noting that the "digital" radio referred to is the In Band On Channel (IBOC) system used only by the U.S., and manufactured by Ibiquity.

    The rest of the planet wisely chose a system that was entirely digital, and which consequently does not have these problems, while the Americans, defending the inalienable right to own radio stations using 1930s technology, or some such thing, fought for a system which sqeezes a digital audio stream into their existing AM or FM signals.

    An all round bad idea, and
    • IBOC is a depricated term. It is now HD Radio [ibiquity.com]
    • Re:Ah, those Yankees (Score:3, Interesting)

      by Detritus ( 11846 )
      The "rest of the planet" is a gross exageration, try Western Europe, South Korea and Canada, with limited availability of radios and small audiences. It's also based on a broadcasting model that is a poor fit for the United States.
    • 1930s technology (if unaltered) would work just fine. People would be getting a quality analog signal, there would be minimal interference, everyone would be happy. The problem is using y2k technology overlaying 1930s technology.

      This is not unusual in the US, in any area of technology. I've seen USians build major roads with nothing more than sand for a foundation - 2000AD cars running on 2000BC infrastructure. Sure, the roads break up badly, and I'm certain there are many accidents and deaths on US roads a

      • This is not unusual in the US, in any area of technology. I've seen USians build major roads with nothing more than sand for a foundation - 2000AD cars running on 2000BC infrastructure. Sure, the roads break up badly, and I'm certain there are many accidents and deaths on US roads as a result, but cheap & quick seems to be the in-thing. Thomas Telford these guys are not.

        In what state?

        I was about to call BS on that, but then I remembered about this thing called "The South," and I thought maybe I'd check
        • South Carolina, specifically Charleston. They use a thick layer of plain sand, add a thin layer of gravel (which they crush) and then they spray the pulverized rock with blacktop. Or it might be coffee grounds. Hard to tell.
  • In particular, it causes neighboring FM stations to disappear if they are lower-powered or further away (a common experience when listening in the car). For example, when 107.7 in San Francisco turned on IBOC, it made 107.5 from Santa Cruz (the famous KPIG) disappear from the south bay.

    In my experience, it also degrades the analog FM signal (of the IBOC broadcaster) with additional multipath.

    It's sad that the FCC will go after 2 watt pirate broadcasters, but not care about interference on a much larger

  • For the same reason that the FCC keeps certifying cell phones, CD players, and laptops that interfere with planes [slashdot.org]. Clearly the FCC cares more about corporate profits than their stated mandate of preventing interference in the radio spectrum.

    Heads need to roll at the FCC, they are not doing their job.

    -- Bob

  • A guy working at a radio station once told me that the large networks pretty much own the market. It used to be small independent radio stations, but not anymore. Like record labels. There are some small ones, but they occupy such a small marketshare that they are almost neligable.
  • I'm not sure why any of the broadcast stations are bothering with it. If they really cared about audio quality, they wouldn't have an Optimod cranked up to 11 in their audio chain. Most people wouldn't believe how good a properly run AM or FM station can sound, they've never heard one.
  • IThe worst source of noise in the AM, FM, VHF, and UHF spectrum comes from the poorly designed and shielded switching power supplies that are now almost universally used. I use the HF spectrum for communication, and my power supply for my laptop wipes it out. It even interferes with my TV. I know its the supply as I am an electrical engineer who has done some design work for these types of power supplies. Plus, as soon as I turn off the supply, the interference goes away. Unfortunately, it is very ha
  • The question is... (Score:4, Informative)

    by Alioth ( 221270 ) <no@spam> on Thursday March 02, 2006 @05:40PM (#14838598) Journal
    The real question is - why is it only in the US that these odd technology hacks are being used - the rest of the world is using DAB for digital broacast radio. It seems like the US is the only place that WON'T be using DAB.
    • The real question is - why is it only in the US that these odd technology hacks are being used - the rest of the world is using DAB for digital broacast radio. It seems like the US is the only place that WON'T be using DAB.

      Because the US needs an IBOC solution, which DAB isn't.

      Besides, DAB isn't exactly taking the world by storm, as you imply. There are a lot of problems with the system (such as smaller stations having to depend on the largerones), which is making DRM (Digital Radio Mondiale) on 30MHz+ loo

      • Well, in the case of 240v 50Hz, it is better - at least I can power an electric kettle off a normal wall socket without having to wait forever for it to boil. 240v is MUCH more practical than 110. I don't need special supplies to run a tumble dryer - that just runs off a normal wall socket too.

        Real Man's electricity, is 240v. If it ain't strong enough to electrocute, what's the use? :-)
        • Well, in the case of 240v 50Hz, it is better - at least I can power an electric kettle off a normal wall socket without having to wait forever for it to boil.

          You can on 120V as well (and 50/60Hz doesn't change anything). In fact George Foreman-branded electric grills have been quite popular for some time.

          The voltage really doesn't matter, it's voltage times current. I don't know what current your typical wall outlets can support, but 20 amps is pretty standard in the USA, and there are very, very few item

  • by jejones ( 115979 ) on Thursday March 02, 2006 @06:08PM (#14838827) Journal
    All you have to do is look at the AM stereo fiasco [wikipedia.org].
  • You know, the slashdot uproar when industries fail to standardize is matched only by the uproar when they do standardize. Why did they only approve one? The stakeholders (manufacturers, stations, govenment) got together and made a decision to go with an established technology. The last thing we needed was a radio format war.
  • FM: 96K bit

    AM: 32K bit

    They use a codec similar to AAC.

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