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Science Technology

Amateur Lightwave Tricks 96

Posted by timothy 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."
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Amateur Lightwave Tricks More

Amateur Lightwave Tricks

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  • Cripes! (Score:1, Troll)

    by morhoj ( 573833 )
    That had to be the single largest concentration of annoying websites in a single post!

    Music, blinds, awful colors, oh my!

  • 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*
    • 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.
      • Um, that would be seriously cool as Alpha Centauri is a little over four light years away so they would have had to start in 1994 to try bouncing a signal off of it...
    • "Amateur Lightwave Tricks"

      The flashy lights werent so bad. But they were on a black background. And there was a looping soundwave also. I think these people are focusing too much on HOW to communicate, and not WHAT they are communicating..
  • Instead of lasers, why don't they look for ill-tempered Seabass...
  • Yep, light's great for communicating with cats. That, and hitting low passing clouds... Glad that's cleared up.

  • Highest usable frequency? (Score:3, Interesting)

    by Tablizer ( 95088 ) on Tuesday June 25, 2002 @06:24PM (#3765851) Journal
    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.
    • 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.
      • 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.
      • (* ....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.
      • The reason there is no response is because no one is listening.

        Bill O'Reilly is faced with this reality every day on his radio program...

    • [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!"

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

    DFossMeister
  • Lasers in space? They don't have to look far. In fact, NASA knows about a giant "laserbeam" [uncoveror.com] on the moon!
    • I have no reference websites to be slashdotted, but on a more serious note NASA did in fact have something to do with a laser on the moon. I forget why, but they bounced a laser off a mirror that was set up on the surface by Apollo astronauts. Come to think of it, it was some experiment to find out how far away the moon is. Although I'm sure that they would have figured that out before they sent the Apollos... Perhaps someone knows more about it?

  • Amateur Lightwave Tricks (Score:3, Funny)

    by NanoGator ( 522640 ) on Tuesday June 25, 2002 @06:28PM (#3765874) Homepage Journal
    "Amateur Lightwave Tricks"

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

  • If people are using different "bands" of electromagnetic radiation to communicate and/or conduct interstate commerce, does that then bring such communication within the purview of the US Government's regulatory ability?

    I don't know (and don't have time to look it up right now) if the FCC's regulation applies to "radio transmissions" or "electromagnetic transmissions" and if it does, does one need a license to use this "new" medium?

    What about NOAA [noaa.gov]? If people are hitting clouds, should the National Weather Service get involved?

    *shrug* just a thought...

    • Re:FCC (Score:2, Interesting)

      by Quixotic137 ( 26461 )
      Ham radio operators are allowed to use all frequencies above 300 GHz. Light falls into that category.
    • 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.

  • a comprehensive laser guide (Score:3, Informative)

    by lingqi ( 577227 ) on Tuesday June 25, 2002 @06:32PM (#3765893) Journal
    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 [repairfaq.org]

    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.

    • (* 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.

      • 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.
    • Another excellent, and more visual, introduction to lasers is Britney's Guide to Semiconductor Physics [britneyspears.ac] :)

  • Ronja (Score:4, Interesting)

    by cr0sh ( 43134 ) on Tuesday June 25, 2002 @06:46PM (#3765948) Homepage
    What lasercomm discussion would be complete without it?

    From the Ronja homepage [mff.cuni.cz]:

    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...

  • Alien waves... (Score:2, Flamebait)

    by josh crawley ( 537561 )
    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 ;)

    • If I was an interstellar commuter (alien), I'd transmit information in the form of directed gravity waves.

      This assumes a few things, but I'll let that slide in lieu of my preferred response: If you had that degree (or better) of control over gravity, why send a message at all? Why not just warp space and make contact in-person?

      Surely you would have the time, you could adjust your local gravitational field to slow the passing of time relative to you.

  • oops (Score:4, Funny)

    by bilbobuggins ( 535860 ) <bilbobuggins@[ ]tjunt.com ['jun' in gap]> on Tuesday June 25, 2002 @06:50PM (#3765967)
    Hams are moving to really high frequencies

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

  • Fun with long-distance lasers (Score:3, Informative)

    by Beryllium Sphere(tm) ( 193358 ) on Tuesday June 25, 2002 @06:50PM (#3765969) Journal
    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.
  • "Hams are moving to really high frequencies "

    OK... that's just freaky... there are pigs on our airwaves?

    What type of shows are they offering?

  • I broke out my telescope to search for some alien lasers, and oh god! MY EYE! IT BURNS IT BURNS!
  • Meanwhile, other amateurs are looking for alien lasers pointed our way

    I hope they remember not to look directly into the beam.

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

    -Vic

  • 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.
    • Someone's been reading a little too much Niven.
    • and that pinpoint of green light was probably a thermo-nuclear reaction several thousands of miles across or even an explosion that was millions of miles across.

      I highly doubt that a super weak laser beam wound be as visible as a massively powerful output of a STAR.

      please people ,get real. a laserbeam that would be visible from alpha centauri from earth, the laser equipment would be the size of australia and the output optics would be the size of texas.

      little pissant beams that are 10KW to 100KW in power are not noticable over space distances.
  • Dammit, when you said 'Lightwave' and 'amateur' I thought it was an article about computer animators! :/
  • I've been designing electronics for aerospace for years both at government facilities and at private companies like my present, Surrey Satellite [sstl.co.uk]. Yes, in this small company we make entire spacecrafts, from micro and mini satellites (LEO) to big GEOs hopefully soon.

    ..And let me tell you that it is quite funny to hear the term "AMATEUR SATELLITE". Come on, what the hell is this supposed to be? If you put a satellite out in space and have it working for a couple of years then you are not an amateur regardeless of any other consideration.
    • 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)

  • Did you... (Score:2, Funny)

    by lord_codah ( 587194 )
    make the quote sign with your fingers when you said "laser" and did you say it aloud like "layyyyserrr"? Just wondering.
  • From the article:

    My sister (a four cat owner) suggested purchasing one of those inexpensive laser pointers to keep the cats busy. Sure enough, two of our three felines, Molly and Junior, love chasing the laser beam wherever I happen to point it--typically all over our family room

    I could have sworn I've seen this before:

    http://www.delphion.com/details?pn=US05443036__ [delphion.com]

  • it says "do not look at beam with remaining eyes..."

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