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World's Smallest FM Radio Transmitter Created With Graphene

minty3 writes "The team used graphene's mechanical 'stretchability' in order to create a voltage controlled oscillator (VCO) – an electronic component that can generate an FM signal. The VCO was used to send and receive audio signals of 100 megahertz. The team used pure tones and more complex music signals to tune the VCO's output and found that both kinds of signals could be 'faithfully reproduced' by an ordinary radio receiver."

37 of 60 comments (clear)

  1. *world's smallest VCO by Joining+Yet+Again · · Score: 1

    Is the size of the VCO a big deal in manufacturing of any radio transmitter?

    1. Re:*world's smallest VCO by drinkypoo · · Score: 2, Insightful

      Is the size of the VCO a big deal in manufacturing of any radio transmitter?

      Only for people interested in listening in on other people without their knowledge. I can't imagine anyone wanting to do that, though. Besides, you'd need a barely visible microphone to make it useful.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    2. Re:*world's smallest VCO by Thanshin · · Score: 4, Interesting

      The world will change once someone builds a quad-copter with microphone and radio transmitter, all fitting in a 0.1mm cube.

      Politicians will have to never, ever, ever, say what they think.

    3. Re:*world's smallest VCO by Joining+Yet+Again · · Score: 1

      I'm happy to be viciously corrected by anyone who's done the sums, so... could a low power radio transmitter be powered by the very sound waves which are being picked up? Tiny microphone, tiny VCO+amp, tiny transducer -> everlasting bug.

    4. Re:*world's smallest VCO by Thanshin · · Score: 1

      It essentially depends on weak a sound you want to hear.

      It may be better to make it solar powered.

    5. Re:*world's smallest VCO by SuricouRaven · · Score: 1

      Because the fly on the wall is still too noticeable. We need the flea on the wall.

    6. Re:*world's smallest VCO by fuzzyfuzzyfungus · · Score: 2

      Because the fly on the wall is still too noticeable. We need the flea on the wall.

      If anybody is going to fulfill DARPA's request for hybrid electronic/biological cyborg surveillance insects, they'll need some pretty tiny electronic gear....

    7. Re:*world's smallest VCO by wbr1 · · Score: 3, Insightful

      You don't even need this when most people willingly carry a remotely accessible microphone and transmitter in their pocket.

      --
      Silence is a state of mime.
    8. Re:*world's smallest VCO by Joce640k · · Score: 1

      Politicians will have to never, ever, ever, say what they think.

      Other possibility: Stop hiring politicians who think things like that.

      PS: How about a link to an article that actually tells us the dimensions of the "smallest transmitter" and some of the the science behind it, not some news aggregator whose other headlines are things like, "3 Signs Your Relationship is in Trouble".

      --
      No sig today...
    9. Re:*world's smallest VCO by Muad'Dave · · Score: 1

      The actual size might not be a big deal, but if the atomically thin size provides better thermal stability or phase noise, then it's a major win regardless.

      --
      Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
    10. Re:*world's smallest VCO by lapm · · Score: 1

      How do you know they haven't done that all ready? What we see in civilian side is always few years back from Military/Super secret spy stuff. You dont think army spends all that money just for guns and ammunition do you?

    11. Re:*world's smallest VCO by CanHasDIY · · Score: 2

      You don't even need this when most people willingly carry a remotely accessible microphone and transmitter in their pocket.

      Except that the people willingly carrying microphones and transmitters aren't the people they need to be listening to.

      --
      An enigma, wrapped in a riddle, shrouded in bacon and cheese
    12. Re:*world's smallest VCO by n1ywb · · Score: 1
      --
      -73, de n1ywb
      www.n1ywb.com
    13. Re:*world's smallest VCO by sjames · · Score: 1

      You don't think people would want a compact all bands cellphone with a cheap efficient transmitter?

    14. Re:*world's smallest VCO by rot26 · · Score: 1

      Big fleas have little fleas on their backs, which bite 'em. And so on and so on, ad infinitum.

      --



      To ensure perfect aim, shoot first and call whatever you hit the target
  2. 100 Mhz audio? by radaos · · Score: 5, Insightful

    Audio signals of 100 megahertz? They have perfected ultrasound then.

    1. Re: 100 Mhz audio? by Kythe · · Score: 1

      Technically, it COULD be used to produce an ultrasonic signal, but since we're talking about a VCO, not a transducer, and since those frequencies are more often used for radio, I'm not sure why you'd describe it as an "audio" signal in any case.

      --

      Kythe
    2. Re: 100 Mhz audio? by Kythe · · Score: 1

      Reading the article more carefully, I'm guessing they used ultrasonic transducers for testing purposes. However, 100 MHz would obviously be used more often as a radio carrier.

      --

      Kythe
    3. Re: 100 Mhz audio? by Joce640k · · Score: 1

      Right!

      Whoosh!

      --
      No sig today...
    4. Re:100 Mhz audio? by Fnord666 · · Score: 1

      Audio signals of 100 megahertz? They have perfected ultrasound then.

      Given that they have "faithfully reproduced" the audio by using an ordinary radio receiver and that 100MHz is in the commercial FM broadcast band, it would be reasonable to assume that 100MHz is the carrier frequency being used.

      --
      'The tyrant will always find pretext for his tyranny.' - Aesop's Fables
    5. Re:100 Mhz audio? by bill_mcgonigle · · Score: 1

      The attitude in the GP post of feeling superior for sarcastically pointing out someone minor mistake is not going to make people think you are smart. Don't mod up people for just being an asshole.

      QFT.

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    6. Re:100 Mhz audio? by magic+maverick+ · · Score: 1

      You've got a strange name there Mr 666. You trying to be edgy or something? But I can't help but think that you're not a nice person, whenever I see your name I get all upset.

      --
      HELP MY ACCOUNT HAS BEEN HACKED BY AN ILLIBERAL ART STUDENT SET TO DESTROY THE INTERWEBZ!
    7. Re: 100 Mhz audio? by sjames · · Score: 1

      The graphene has a natural frequency that is changed by mechanical tension (like a guitar string). They tuned it to 100MHz. Then, an audio transducer modulated the mechanical tension (and so, the frequency of the graphene) to produce an FM radio signal.

  3. The actual size by Thanshin · · Score: 2

    Strange to claim it's the "World's Smallest" and not give it's size.

    I'd guess 4m x 10m?

    1. Re:The actual size by Thanshin · · Score: 1

      I meant micrometers. For some reason, /. didn't like the [micro].

    2. Re:The actual size by Joce640k · · Score: 1

      Strange to claim it's the "World's Smallest" and not give it's size.

      You must be new here.

      Don't ever expect Slashdot to link to a proper article instead of a crappy news aggregator site.

      --
      No sig today...
    3. Re:The actual size by Sockatume · · Score: 1

      Looks like the superstructure is about 6x6 micron, with the oscillator in the middle being a 2-4 micron diameter circle of graphene.

      --
      No kidding!!! What do you say at this point?
    4. Re:The actual size by Sockatume · · Score: 1

      Any reasonable definition of nanotechnology simply requires that one or more component be in the nanometre range; given that the vacuum gap in the oscillator is 5-200nm depending on the device, that sounds fair.

      --
      No kidding!!! What do you say at this point?
    5. Re:The actual size by mcgrew · · Score: 1

      Don't ever expect Slashdot to link to a proper article instead of a crappy news aggregator site.

      Don't blame slashdot, first blame the submitters -- they're the ones supplying the links. Next, blame yourself for not voting down stories with shitty links and then submitting your own with a good one.

      And since you got me to post this offtopic answer, Buy my book! Or at least read it. Just to make up for the downmod!

  4. Significant new type of oscillator by Anonymous Coward · · Score: 5, Informative

    What they have demonstrate is how a graphene structure can be made into a tunable oscillator by constructing a rather crude but working FM 'radio-transmitter' using one.

    Its significant because older mechanical oscillators were based on crystals or MEMS stuctures that are rather more 'large' than "a one atom-thick graphene sheet" and in practical applications often require considerable space and volume on a circuit board or inside a die package.

    If this structure could be incorporated into the microlithography process that is used in making 'electrics chips' then a large external component could be omitted from designs. You could also include multiple independent oscillators on the same die that requires them allowing for more precise control of frequencies needed.

    AC cause I can't be bothered to login - more Karma for dev/null ^^

  5. Re:Range? by Kythe · · Score: 1

    If it's just a VCO, it would really depend on the transmit amplifier in any case.

    --

    Kythe
  6. Supplementary information by martyb · · Score: 3, Interesting

    What they have demonstrate is how a graphene structure can be made into a tunable oscillator by constructing a rather crude but working FM 'radio-transmitter' using one.

    You are correct. And crude is an apt choice of wording... From the supplementary information (scroll to the bottom), there are links to: pdf containing data on setup, testing, and characterization as well as a .wav file (confusingly labeled "movie"). It appears to be a sample of a transmitted sound sample of "Gangnam Style!"

    The sound quality of this sample is more on the order of a noisy AM radio broadcast, but given the technology being used, quite impressive, nonetheless.

    FWIW, there is a (somewhat) better write-up at redorbit.

    And, yes, the 100MHz in TFS refers to the carrier frequency, which is but one of several that they tested. But, it also happens to be in the FM radio band and hence the (attention-grabbing) title.

    1. Re:Supplementary information by TheCarp · · Score: 1

      > It appears to be a sample of a transmitted sound sample of "Gangnam Style!"

      And another opportunity to Rickroll entire communities is lost.

      --
      "I opened my eyes, and everything went dark again"
  7. Cool but... by shellster_dude · · Score: 2

    Wake me up when they have created the world's smallest graphene violin!

  8. The power of graphene by Applehu+Akbar · · Score: 1

    So this is what brings us those tiny PBS relay stations we briefly encounter in a cross-country drive?

  9. Finally! by havana9 · · Score: 2

    We can broadcast the world's saddest song on the world's smallest violin with the smallest FM transmitter!

  10. Tinfoil hat time by vlueboy · · Score: 1

    Think of the implications this can have for us with the NSA bundling it. I wouldn't be surprised if this similar tech is already snooping on us.
    No amount of de-wiring the obvious attack points will help. Seriously, the world is getting extremely inconvenient to live in when it comes to computing we can trust.