Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror
×
Communications Technology

70th Anniversary FM Commemorative Broadcast 109

Anonym1ty writes "A special commemorative FM broadcast Saturday, June 11, at noon (EDT) will mark the 70th anniversary of Edwin H. Armstrong's first public demonstration of wideband frequency modulation (FM). The transmission, from Experimental Station WA2XMN (reminiscent of Armstrong's W2XMN call sign) will be on Armstrong's original 42.8 MHz frequency and will emanate from his landmark 400-foot Alpine Tower in NJ. The program will tell the tale of FM's difficult birth, as well as its impact on present-day communications and will include excerpts from a recording of a 1941 test broadcast of the New England Yankee Network. For those unable to receive 42.8 MHz FM, the broadcast is being retransmitted by WFDU-FM on 89.1 MHz and via the Web. Rebroadcasts will take place June 14 and 16 at 7 PM (EDT)"
This discussion has been archived. No new comments can be posted.

70th Anniversary FM Commemorative Broadcast

Comments Filter:
  • Clear channel (Score:3, Insightful)

    by cataclyst ( 849310 ) on Friday June 10, 2005 @06:45PM (#12785652) Homepage
    Good thing that FM radio has been used for so much good since then. 70 years later, and half the stations play the same 5 songs, over and over and over...

    Wonder if he saw that coming...
  • Also available to everyone via immediate download via BitTorrent
  • Radio (Score:3, Insightful)

    by treff89 ( 874098 ) on Friday June 10, 2005 @06:47PM (#12785670)
    Hasn't radio been one of _the_ most important inventions of all-time? We use it for everything now: 802.11x, microwaves, television, some Internet... lots of stuff to do with digital. :P It's been so incredibly useful that it's actually quite a nostalgic event that's about to take place.
    • Re:Radio (Score:2, Informative)

      by cataclyst ( 849310 )
      I dunno about FM's role, however.. not all RF waves are Frequency Modulated.... [like AM, for example]
      • Re:Radio (Score:5, Informative)

        by insignificant1 ( 872511 ) on Friday June 10, 2005 @07:19PM (#12785829)

        Well, FM was and is still important. Popular modulation schemes include both frequency modulation and amplitude modulation, but either is appropriate in different settings.

        One advantage to FM is its relative immunity to certain kinds of noise (often noise is additive, and hence the amplitude is affected directly by noise whereas the frequency is less affected).

        FM is the precursor to (and was at the time) more noise and jam-resistant schemes. The tradeoff is it requires greater bandwidth than AM to transmit a given signal.

        Check out this wikipedia link to find out more about different MODULATION [wikipedia.org] schemes...

      • Phase modulation for example -- needed for most digital radio.
    • Radio waves were not invented, they were predicted by Maxwell and discovered by Hertz.
  • by SeventyBang ( 858415 ) on Friday June 10, 2005 @06:47PM (#12785671)
    ...why does everyone flaunt Marconi when Tesla had voice transmission long before Marconi's public demonstrations were nothing more than Morse?

    • I think it's because Marconi was the first to use run-on sentences like yours.
    • by Anonymous Coward
      Congratulations! You've mentioned one of the "Slashdot top 10 Absolutely flawless person, organization or technology who was unfairly beaten down by The Man" (TM). Your selection was:

      ( ) BeOS
      ( ) Hydrogen-filled Dirigibles
      ( ) Alpha Microprocessors
      ( ) Bell Labs
      ( ) VAX/VMS
      ( ) Betamax
      (X) Nikola Tesla
      ( ) Xerox PARC
      ( ) Alan Turing
      ( ) Amiga

      You can pick up your prize at the front desk.
    • by davmoo ( 63521 ) on Friday June 10, 2005 @10:02PM (#12786688)
      Now that someone else has given you a useless wise-ass grammar nazi reply, I'll try to give you one that actually answers your (very valid) question.

      Because Marconi knew how to work public relations and his supporters. Its the same reason that Edison gets so much credit when Tesla had more to do with how we use electricty today than Edison ever did.

      For a good example, look at how the Smithsonian treats Marconi and Edison in relation to how they treat Tesla. Then look at the records and see how much money Marconi and Edison supporters and family donate to the Smithsonian.

      Tesla was so busy actually inventing useful things that he didn't have time to work the press. Since Marconi and Edison didn't do all that much themselves, they had plenty of time to "press the flesh".
  • by kevcol ( 3467 ) on Friday June 10, 2005 @06:48PM (#12785677) Homepage
    Armstrong also once was working on a live radio transmitter when his finger touched the bare leads of a capacitor.

    Yes, he was the worlds first FM Shock Jock.
  • for us linux users (Score:5, Informative)

    by xbmodder ( 805757 ) on Friday June 10, 2005 @06:49PM (#12785685) Homepage
    To play it via linux:
    mplayer -cache 128 http://64.92.199.76/WFDU-FM [64.92.199.76]
    --
    I hope we can setup some mirrors so during the broadcast they don't get slashdotted. anybody know how to convert asf to mp3? if so someone setup a mother stream. I am writing up a script right now for dynamic redirection on their server.
  • AM v. FM (Score:2, Interesting)

    I think this is particularly cool considering FM almost didn't make it out of infancy. Armstrong worked for RCA and they had so much invested in it that they tried to kill it. He had to pay to put up his own transmitter. RCA even tried running an FM smear and fear campaign. HAHA
    • Armstrong didn't exactly work for RCA, but they certainly worked against him.

      I highly recommend the book Man of High Fidelity: Edwin Howard Armstrong by Lawrence Lessing, if one is fortunate enough to find a copy. (I bought my Bantam Books paperback copy some 30 years ago.)

  • by G4from128k ( 686170 ) on Friday June 10, 2005 @07:00PM (#12785748)
    AM radio's susceptibility to interference makes it fun and useful for "listening" to electronics. For example, an AM radio will let you listen to transmissions on an ethernet cable and tell if it is plugged in and handling traffic. Old programmable calculators make the most interesting sounds as they chug through their calculations. Another plus is that you can hear lightening strikes from a great distance and listen as they approach or recede.
  • by __aaclcg7560 ( 824291 ) on Friday June 10, 2005 @07:05PM (#12785772)
    Any company selling a vacuum-tube radio for the 70th anniversary? I always did love the orange glow from the back of the radio console.
    • I have an old vacuum tube radio. It hasn't been plugged in since forever.

      My MIL was going to throw it out when we were cleaning out her mother's house. Everything is intact, and it's sitting here in the living room, fitting in with the rest of the furniture.

      I've just never come up with the stones to pull the tubes, map their location, dust everything, etc. Everything which needs to be done before I'm willing to plug it in. On top of that, electricity is one of my three phobias. If I ground myself wi
  • by tekiegreg ( 674773 ) * <tekieg1-slashdot@yahoo.com> on Friday June 10, 2005 @07:06PM (#12785778) Homepage Journal
    Why we can't listen to 42.8 on a radio anymore? Forgive me but I'm just a radio newb who just has one in his car. Thanks!
    • You can pick up this frequency with a scanner.
    • The way radio works is that your car radio has to "tune" to the frequencies that you are listening to. Tuning means you have a little pure-tone synthesizer in your car that produces pure tones at different frequencies.

      Now the real reason why it doesn't tune that low in frequency is because there is virtually no demand to listen to amateur radio bands. And it costs money to make that synthesizer generate more frequencies than required. So you have to pay more money to tune into those frequencies, in the

      • It was actually an FM radio band back before FM broadcasting got moved up to 88-108 MHz. Now it's part of the public service band, as in police, utility companies, forest rangers, etc.

        As was pointed out above, most scanner radios will receive that frequency just fine.
        • There was also a certain element of the AM establishment trying to quash FM -- RCA, I believe, but I don't remember for certain. The frequency shift obsoleted a lot of radios, and I think that particular swatch of low VHF was reallocated to television. It set FM back for years, which was having troubles enough because the owners of FM stations insisted on having them simulcast AM programming instead of doing original programming.

          I suspect commercial FM radio wouldn't really be viable without stereo as well
      • by Anonymous Coward
        Why do people automatically assume that if it is outside the 2 well known broadcast bands that it is amateur radio bands? This is why there has been such a problem with BPL. It seems like most people think that there are the AM broadcast, FM broadcast a handful of TV stations and the rest of the spectrum is in the possesion of the amateurs. Please look at http://www.ntia.doc.gov/osmhome/allochrt.html [doc.gov]
        and tell me what 42.8 has to do with amateur radio.
        • Sorry, it's land mobile / government exclusive (in the USA), dunno what that means. But whatever. It is of no use to Sony to make a tuner to work with 42.8 MHz. Thought it was amateur because of the nostalgic broadcast on it; not something I'd expect in other bands.

          And you might have problems with BPL because... well... what is BPL?

    • Yeah, really. It only goes from 88 to 108. I often wondered what kind of great stuff we might be missing on, oh say, 75.
      • IIRC, 72-76 Mhz is used for low-power short-range communication systems such as hearing aids. Yes, that's right, hearing aids. Ever go to a movie theatre, church, auditorium, etc., that has signs up that tell hard-of-hearing people to "ask for a receiver?" - those systems usually run in the 72-76 band - I'm not sure of the exact channel frequencies - but they are very popular in schools where deaf or hard of hearing students are in school.

        The great thing is, that these systems take the program audio - that
      • Old radios in Germany were perfectly capable of tuning way under 88. They only had some mechanical lock that prevented listeners from tuning that fare. By removing the lock as a kid I could listen to police car transmissions :)
      • BTW, some people here in Finland complain they can't receive 87.5-88.0 MHz, that has FM public radio transmissions here in Finland. Apparently that is part of FM band, but some radio sets tune only 88+ MHz.
    • Funny, I just wrote a report on this for a class.. I'm posting this too late for it to be moderated I think, but I hope someone reads it:

      On June 27, 1945, the FCC moved the FM band to 88-106 MHz. It has originally occupied the 42-50 MHz band. This may appear to be only a small change, but the story behind it is immense. Edwin H. Armstrong had invented frequency modulation in the early 1930s (it was patented in 1933, and his paper, "A Method of Reducing Disturbances in Radio Signal by a System of Frequen
  • by Saint Aardvark ( 159009 ) * on Friday June 10, 2005 @07:07PM (#12785779) Homepage Journal
    ...as part of his book Free Culture [sourceforge.net] (available now if you sign up as a member of the Free Software Foundation [fsf.org]. Do it today!). Before you think it's boring, or that things today are completely different from how they ever have been, read:

    As our own common sense tells us, Armstrong had discovered a vastly superior radio technology. But at the time of his invention, Armstrong was working for RCA. RCA was the dominant player in the then dominant AM radio market. By 1935, there were a thousand radio stations across the United States, but the stations in large cities were all owned by a handful of networks.

    ....Armstrong's invention threatened RCA's AM empire, so the company launched a campaign to smother FM radio. While FM may have been a superior technology, Sarnoff was a superior tactician. As one author described, "The forces for FM, largely engineering, could not overcome the weight of strategy devised by the sales, patent, and legal offices to subdue this threat to corporate position. For FM, if allowed to develop unrestrained, posed ... a complete reordering of radio power ... and the eventual overthrow of the carefully restricted AM system on which RCA had grown to power."

    ....Armstrong resisted RCA's efforts. In response, RCA resisted Armstrong's patents. After incorporating FM technology into the emerging standard for television, RCA declared the patents invalid--baselessly, and almost fifteen years after they were issued. It thus refused to pay him royalties. For six years, Armstrong fought an expensive war of litigation to defend the patents. Finally, just as the patents expired, RCA offered a settlement so low that it would not even cover Armstrong's lawyers' fees. Defeated, broken, and now broke, in 1954 Armstrong wrote a short note to his wife and then stepped out of a thirteenthstory window to his death.

    ....This is how the law sometimes works. Not often this tragically, and rarely with heroic drama, but sometimes, this is how it works. From the beginning, government and government agencies have been subject to capture. They are more likely captured when a powerful interest is threatened by either a legal or technical change. That powerful interest too often exerts its influence within the government to get the government to protect it. The rhetoric of this protection is of course always public spirited; the reality is something different. Ideas that were as solid as rock in one age, but that, left to themselves, would crumble in another, are sustained through this subtle corruption of our political process.

  • American radio stations register with the FCC, and get a station name of a few letters. West of the Mississippi, stations get an initial "K"; eastern stations get an initial "W". Why those particular letters? Why choose "W", the longest and most difficult letter to say, as a generation of Websters have rediscovered three times over?
    • I always heard it was because one of the first stations, like WWJ or something, was sponsored by something that started with a W. It was just an acronym, but it stuck.

      yahoo [yahoo.com] feels differently, but they don't seem to know any more about it than me.

      • Still searching. BTW, though Yahoo cited an early source for the system of letter assigments, they don't answer why those particular letters were chosen, whenever they originally were. But then, the "answerer" calls the questioner's mistake (that all US radio stations names start with "W") a "semantic" mistake, so I don't expect precision or rigor from them.
      • Probably Westinghouse
    • Re:Letter Imperfect (Score:2, Informative)

      by SPY_jmr1 ( 768281 )
      Two seconds on google... http://earlyradiohistory.us/recap.htm [earlyradiohistory.us]
      • Re:Letter Imperfect (Score:3, Interesting)

        by Doc Ruby ( 173196 )
        And 5 minutes reading that history page reveals only

        "I don't know why K and W were chosen for the initial letters, or why the Bureau thought it necessary to split the assignments into two geographic groups"

        And that you either didn't read the question, or the answer, or maybe both. But at least now we all know you don't, which my own Google search did not reveal.
        • Re:Letter Imperfect (Score:3, Informative)

          by SPY_jmr1 ( 768281 )
          *grumble*

          You would be correct.. I didn't read the history page that closely.

          Therefore: "Here is a possible explanation as to how the USA got W and K, no documentation on this but sounds plausible. The USA had unofficially used N for North America (e.g., NBZ, Boston), also A for America. The letter "N" in morse is dah dit, adding a dah to N gives dah dit dah which is "K'. Letter "A" in morse is dit dah, adding a dah to A gives dit dah dah which is "W"."

          source: http://www.ac6v.com/history.htm/ [ac6v.com]
          • That's closer, but not exactly compelling. After all, why add a "dah", not a "dit", especially when it would yield a letter so hard to say? Of course, I can't deny that claimed origin, but it's not distinguishable from a contrivance atop coincidence. The US had a vast fleet, huge territory (needing lots of radio), and a legitimate (Tesla) claim to inventing radio itself. Why couldn't it just choose whichever letters most convenient, instead of one which is the least convenient?

            I'm hoping, by posting in a t
            • As somebody with a WD call, I think WD has a nice sound to it. dit-dah-dah, dah-dit-dit. They obviously had me in mind.

              hi.

              I'm also amazed from time to time how many /.ers seem to know a bit of Morse.

    • The starting letters for call stations of radios was set by international standards, the US got K and W, why they chose to split it there i dont know
      • As well as K and W the US also gets N and some of the possibilities starting with A. N and A just don't get used for comercial broadcast stations.

        I've always wondered if US aircraft tail numbers starting with N have somthing to do with using tail numbers for radio call signs.
        • I've wondered the same thing, though "callsign" has a somewhat different meaning in aviation than in radio.

          Yeah, the US has a rather large chunk of namespace. A and N seem to be mostly used by military and amateur stations -- almost everything else is W and K. Usually if you buy a license for your GMRS walkie-talkies (you did buy a license didn't you?) you get a W callsign.
    • Re:Letter Imperfect (Score:3, Informative)

      by soren42 ( 700305 ) *

      Actually, US radio call signs begin with A, W, K, or N. The FCC has decided which service classes may use which call groups (e.g., broadcast stations are only assigned calls starting with W & N).

      The entire alphabet is maintained by the International Telecommunications Union (ITU) and its precursors. The earliest assignment of these call letters to the US dates back to early radio in 1913, and has been maintained ever since.

      73 de N4JCK
      • Here's the whole list [wikipedia.org], if anyone is interested.
      • Do you know why those letters are the ones available? Specifically "W", which has so much to recommend against it, at least in America.
        • A, K, N & W



          A stands for America



          in morse code it is .-



          K is like an A in morse code with a dah before it -.-



          N is like an A only backwards -.



          W is like an A with a - after it .--



          We have more people (stations) in the US than most other countries, we needed more letters.

          Yup that is why we have A, K, N & W.

          • That's the most plausible explanation I've "heard". Do you have any citations to show its historical accuracy?
            • Also, the prefixes are a result of international agreement. Before the agreement hams had calls like 3FG. The holder of 3FG became W3FG afterwards. This implies WARC or its predecessor(s) sat down and devided up the alphabet. Presumably countries had some influance over what they got, so we can assume the US wanted A, K, N and W for some reason.

              Some of the others sort of make sense, G for Great Britan. F for france. Canada gets only some of C.
            • That's the most plausible explanation I've "heard". Do you have any citations to show its historical accuracy?

              I have heard it in ham radio theory classes... and read it in books... but I can no longer remember the sources. -But it was from several sources. Should I run accross one of them, i'll try to remember to atleast make a reference to it in wikipedia

  • by Bananatree3 ( 872975 ) on Friday June 10, 2005 @07:09PM (#12785792)
    It is possible to transmit FM signals unlicenced, as you can probably find from your iTrip, etc. You can find the regulation on it here: http://www.fcc.gov/mb/audio/lowpwr.html [fcc.gov]
  • Will there be a rush on Thomas Salter Crystal Radio sets in the morning amongst the radio ham community? And is 70 really a birthday worth going to town for? 75, or 100, yes. 70?
  • WLW (Score:4, Interesting)

    by Deathlizard ( 115856 ) on Friday June 10, 2005 @07:40PM (#12785930) Homepage Journal
    Maybe it's just me, but I always thought WLW was a more interesting station.

    500,000 100% modulated watts is a little crazy. you would have to practially feel it on a humid day.
  • by argoff ( 142580 ) on Friday June 10, 2005 @08:25PM (#12786180)
    I'm serious. While FM is nice, there are a lot of new technologies that permit digital communications over multiple frequencies (or even multiple directions on the same frequency) that are simply better than FM and and are held back for no other reason than cumbersome regulations and the notion that frequencies should be disected into chuncks of teritory like property. Property is about things that have real natural limits in supply and demand, not about things that have regulatory limits simply for the sake of locking in an industry and a particular technology.
    • "Property is about things that have real natural limits in supply and demand..."

      And the FCC was created because the airwaves are subject to those limits and somebody had to decide how to share them. Spectrum is like land, they aren't making any more of it.

    • by connorbd ( 151811 ) on Saturday June 11, 2005 @12:16AM (#12787379) Homepage
      The only way to accomplish this would be to rebuild the entire radio communications system from the ground up, and not allow anyone to use anything else. That is so not going to happen -- the problem is akin to tearing down a city and rebuilding it from the subterranean level up. It's not that it isn't possible -- it's just that it would cost so much money and displace so many people that there's no reason on earth why anyone should think it a good idea. (The few cases where such a thing is possible -- postwar Germany, Kabul, Beirut, Nero's Rome, Banda Aceh -- it's been because of war or natural devastation.)

      People who make this assertion don't really understand the nature of radio waves. You can't simply switch everyone over to a 5GHz spread spectrum scheme -- the propagation characteristics are very different at 1100 KHz, 25 MHz, 100 MHz, 460 MHz, 900 MHz, and 2.4 GHz (to take a half dozen frequencies in commonly used areas). The regions above about 6 GHz are pretty much useless for anything but short-range communication, satellite communication, and radar, while the CB bands at 27 MHz are superbly unsuitable for their intended purpose because they're potentially capable of worldwide propagation given proper ionosphere conditions.

      If you want an idea of what an unregulated radio world, look at a shortwave guide and see what the US offers. How many of them aren't religious broadcasters? How many of them broadcast far-right tripe? Look at the CB bands and see what kind of crap goes on there, in a 40-channel swatch that the FCC gave up on enforcing years ago. Eventually you'd have nothing but a vast swatch of radio anarchy, with jammers, rednecks, and general troublemakers shouting down anyone they don't like.

      Or you could just google the callsign KG6IRO or name Jack Gerritsen and find out why that fellow recently went to jail for what he did with his ham radio equipment. Talk all you want about the nobility of your cause and giving the airwaves back to the people, but if there was such a thing as radio anarchy, there'd be a lot more douchebags like Gerritsen out there.
  • People still have them? I thought they went out years ago once satellite radios [sirius.com] came into being.
  • Anyone else notice 1337 engraved at the top of his transmitter building?
  • See? (Score:3, Interesting)

    by iminplaya ( 723125 ) on Friday June 10, 2005 @10:24PM (#12786819) Journal
    FTA:
    Throughout the 1940s he continued to lose money on promoting FM radio, fighting protracted patent litigation, and attempting to ward off regulatory attempts. He desperately craved recognition, bringing lawsuits and writing letters to the editor in an effort to demonstrate his accomplishments. Colleagues recognized his brilliance but viewed his desire for glory as obsessive and unnatural. Ill and despondent, in 1954 Armstrong put on his evening coat, hat, and gloves, and stepped out the window of his thirteenth-floor Manhattan apartment.

    THIS is what IP law will get you.

This is the theory that Jack built. This is the flaw that lay in the theory that Jack built. This is the palpable verbal haze that hid the flaw that lay in...

Working...