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Amateur Lightwave Tricks

Posted by timothy on from the weighs-nothing-says-much dept.

HobbySpacer writes: "According to an ARRL article, some Hams are moving to really high frequencies with experiments using lasers & LEDs. The tests include cloudbouncing, moonbouncing, laser radar and an infrared laser on an amateur satellite. See the Lasercom Manual and this paper for intros. Meanwhile, other amateurs are looking for alien lasers pointed our way."

30 of 96 comments (clear)

  1. Yikes by Wrexen · · Score: 2

    Apparently the moonbouncing site is being updated from at least beyond Alpha Centuri, seeing as how its design dates from circa 1996. *cowers under desk from BLINK tag flashbacks*

    1. Re:Yikes by NanoGator · · Score: 2

      Shit dude, I misread that. I thought you were implying they bounced radio signals off of Alpha Centauri. Heh. That'd be seriously cool if they got that to work. Something like that would prove that SETI could recieve a radio signal from another star. (or possibly prove that it can't...) That'd either improve SETI's funding, or cause them to rethink their approach.

      --
      "Derp de derp."
  2. Highest usable frequency? by Tablizer · · Score: 3, Interesting

    I wonder what the highest usable EMS frequency is. An advanced alien civilization would probably be using the highest usable frequency rather than a frequency that is easiest (for us) to generate.

    They might be broadcasting in gamma waves or X-rays for all we know.

    --
    Table-ized A.I.
    1. Re:Highest usable frequency? by T3kno · · Score: 3, Interesting

      Since you insist on creating this advanced alien civilization in our image, you must realize that any advanced alien civilization would therefore be able understand our primitive communications methods and be able to respond using the same said methods. The reason there is no response is because no one is listening.

      --
      (B) + (D) + (B) + (D) = (K) + (&)
    2. Re:Highest usable frequency? by flewp · · Score: 2

      Huh, interesting. Or, the reason there isn't a response is because radiowaves generated by us haven't left our planet till very recently in a cosmic state of mind and it hasn't reached those who are indeed listening.

      Nah, you're arguement is much, much better.

      --
      WWJD.... for a Klondike bar?
    3. Re:Highest usable frequency? by Tablizer · · Score: 2

      (* ....advanced alien civilization would therefore be able understand our primitive communications methods and be able to respond using the same said methods *)

      I meant *intercepting* rather than bi-directional communication.

      --
      Table-ized A.I.
    4. Re:Highest usable frequency? by Tablizer · · Score: 2

      (* We wouldn't recieve anything back for another million or billion years if this was the case. *)

      Perhaps they sent it a million years ago, so we would be getting it now. Besides, I am proposing merely detection or interception, and not two-way communications.

      The alien scenario was partly to stimulate thinking about what limits the frequency used to broadcast. Is it the technology to send and receive, or the nature of the wavelength *itself*?

      Our limit may be the sending and receiving technology we have. However, these may be moving targets as we learn more; and technically advanced beings may be using really high frequencies.

      Perhaps even something like gravity waves or quantum twin particles. Who knows whats possible.

      Engage!

      --
      Table-ized A.I.
    5. Re:Highest usable frequency? by Tablizer · · Score: 2
      [Aliens] might be broadcasting in gamma waves or X-rays for all we know

      I just thought of something if this was the case.

      Every time somebody gets a dental X-ray here, some alien's garage door may be opening up.

      "Dammit, Bleem, you still havn't not fixed it right. It opened by itself again!"

      --
      Table-ized A.I.
  3. Alien lasers by DFossmeister · · Score: 2, Funny

    If I see any aliens with lasers pointed at me, I plan to run! I'm not taking any chances.

    DFossMeister

    --
    No Not Again! Its whats for dinner.
  4. Amateur Lightwave Tricks by NanoGator · · Score: 3, Funny

    "Amateur Lightwave Tricks"

    Shit, I got excited because I thought this was a thread about using Lightwave 3D.

    --
    "Derp de derp."
  5. a comprehensive laser guide by lingqi · · Score: 3, Informative
    Since we are talking about lasers and LEDs etc, so unless everyone reading here knows *that* much about lasers -- i would recommend the following site for everyone:
    Sam's Laser FAQs

    I have spent days pouring over the mass abundance of information there -- and it has convinced me that building a kilowatt CO2 laser to burn though buildings really is something everyone should consider doing for fun.

    --

    My life in the land of the rising sun.

    1. Re:a comprehensive laser guide by Tablizer · · Score: 2

      (* I have spent days pouring over the mass abundance of information there -- and it has convinced me that building a kilowatt CO2 laser to burn though buildings really is something everyone should consider doing for fun. *)

      Osama Jr. has come of age it seems.

      --
      Table-ized A.I.
    2. Re:a comprehensive laser guide by lingqi · · Score: 2

      heh... not that i want to use it for terroist purposes -- but there are some really neat properties about it.

      1) not in the visible spectrum
      2) really f* powerful -- compared with milliwatt laser pointers etc. this *burns*
      3) does not pass though glass (good and bad) -- good - can burn holes through glass; bad - mirrors will cost ya.

      too bad the power requirements means no reasonabbly portable units can be constructed and say, carried in a backpack (ala laser troops in Akira). might be able to mount it on a humvee though.

      --

      My life in the land of the rising sun.

  6. Re:FCC by Quixotic137 · · Score: 2, Interesting

    Ham radio operators are allowed to use all frequencies above 300 GHz. Light falls into that category.

  7. Re:Cats by NanoGator · · Score: 5, Funny

    "Yep, light's great for communicating with cats."

    I laser-guided a cat up my mother's leg once. I don't remember if it was the band-aids or the ruined stockings that cost more, heh. That was a boring weekend I spent in my room, though.

    :)

    --
    "Derp de derp."
  8. Ronja by cr0sh · · Score: 4, Interesting

    What lasercomm discussion would be complete without it?

    From the Ronja homepage:

    Build your own optical data link from common elementary parts - Ronja is an Open-Hardware optical datalink that connects two PC's point-to-point. Ronja's design is licensed under the GNU Public License: you get all the necessary documentation and construction guides free. The construction costs are minimal; it's probably the cheapest wireless system ever. The operation is very
    reliable and immune to interference.

    Take note, people - when the USA Patriot Act enforcers of protocol come, laser may be the only way to comm...

    --
    Reason is the Path to God - Anon
  9. Alien waves... by josh+crawley · · Score: 2, Flamebait

    Why would an intelligent alien culture transmit in a low-density solution like light? That's so low bandwidth (in my opinion). If I was an interstellar commuter (alien), I'd transmit information in the form of directed gravity waves. It travels at the speed of light (perhaps faster), and has IMMENSE data storage due to the quark-size waveform. Why mess with LOS light when gravity is Line-Through-Everything?

    Other than that, amateur light proects are cool ;)

    1. Re:Alien waves... by Tablizer · · Score: 2

      (* Then again they may not be a technologically advanced alien society. Alien != superior *)

      Well, if they are *inferior*, we reallllly *don't* want to contact them anyhow.

      Even equal is a questionable level. They would probably either try to convert us to some funky religion that bans smiling, or spam the hell out of us:

      "Increase All Four of Your Penises by 300 Percent!"

      (Their demographics targeting is not any better there either.)

      --
      Table-ized A.I.
  10. oops by bilbobuggins · · Score: 4, Funny
    Hams are moving to really high frequencies

    I was like 'what? lunch meat I can't hear?'
    God, it's been a long day...

  11. Fun with long-distance lasers by Beryllium+Sphere(tm) · · Score: 3, Informative

    http://www.llnl.gov/urp/science/lgs_www/lgs.html

    They're using a laser to create what looks like a star, above most of the atmosphere. Naked-eye visibility! I wonder how much modulation you could put on it for long-distance communication.

  12. Re:Laser Rangefinding by captain_craptacular · · Score: 4, Funny

    If they'd only remembered to reset the odometer on the Appolos before they left they'd know for sure!

    --
    They who would give up an essential liberty for temporary security, deserve neither liberty nor security
  13. Am I the only one? by krs-one · · Score: 2

    That thought that this article was related to the 3D modeling program?

    -Vic

  14. Re:Cats by scott1853 · · Score: 2

    I'm too lazy to go find the link but somebody has a patent on using a laser pointing device to get a cat to move around. Sadly, I am being serious.

  15. Re:Alien Lasers... by ColaMan · · Score: 2

    That's the sun, hotshot. Try looking for lasers at night.

    --

    You are in a twisty maze of processor lines, all alike.
    There is a lot of hype here.
  16. Green light in Murcheson's Eye (nebula) by Caractacus+Potts · · Score: 2


    If you live in the Northern hemisphere and have at least a 6" Dobsonian reflector telescope, you can check out one of the potential "alien" laser sources by looking at the nebula known as "Murcheson's Eye", also known as D-M073. A pinpoint of green light was once observed in this nebula.

    1. Re:Green light in Murcheson's Eye (nebula) by shogun · · Score: 2

      Someone's been reading a little too much Niven.

  17. Re:Alien Lasers... by Tablizer · · Score: 2

    (* That's the sun, hotshot. Try looking for lasers at night. *)

    Dammit! You are ruining my Darwin Award submission candidate. Hush it!

    --
    Table-ized A.I.
  18. Re:FCC by Andy+Dodd · · Score: 2

    As another poster pointed out, hams have full privileges over 300 GHz.

    Most likely, the FCC has declared the optical region to be an unlicensed band, if not explicitly than implicitly.

    Any regulations on optical transmissions fall under other laws (FAA regulations on lasers, possibly disturbing the peace if you light up your neigbor's bedroom with your comm system, etc.)

    In general, use common sense and no one will care.

    --
    retrorocket.o not found, launch anyway?
  19. The definition of the term "Amateur" by Andy+Dodd · · Score: 2

    I once read an article describing the meaning of the word "amateur" in the case of amateur radio.

    In this case, it's "amateur" in the Olympic sense of the word - One who practices an art but is not paid for it. (As opposed to professional, which implies "for pay") - Think of amateur figure skating. Some of the best figure skaters in the world are considered "amateurs" simply because they do not skate for money. (As opposed to professional skaters, such as those in the Ice Capades)

    --
    retrorocket.o not found, launch anyway?
  20. Did you... by lord_codah · · Score: 2, Funny

    make the quote sign with your fingers when you said "laser" and did you say it aloud like "layyyyserrr"? Just wondering.