Connect with us

[OT?] Off-the-shelf radio beacon?

Discussion in 'Electronic Basics' started by Wildepad, Oct 26, 2007.

Scroll to continue with content
  1. Wildepad

    Wildepad Guest

    This is probably off-topic because it's for an sf story rather than
    something I'm actually trying to do, but I need a real-world answer. I
    will appreciate your sharing your expertise, knowledge, and

    Is there some sort of reliable beacon that is available off-the-shelf,
    is easy to use, and does not require government permits to purchase or

    It has to be quickly set up and easily guide someone to it from
    distances up to 100+ miles away.

    'Easy to set up' can include parking a trailer on the top of a hill,
    anchoring it, cranking up an antenna, folding out the solar panels,
    and driving in a ground rod.

    It cannot include anything requiring on-site electronics/rf knowledge.
    It also cannot take more than about an hour to deploy.

    'Easy to use' would be best as a handheld unit with an LED that lights
    when pointed at the unit, but it can also include holding up a
    transistor radio and sweeping it back and forth to get the general

    It cannot require rotating an antenna (ala the classic radio direction
    finder) because it is possible that the user will have to abandon
    their vehicle. Things like distance readouts or similar would be nice,
    but is nowhere near being required.

    Although it needs to be off-the-shelf for a variety of reasons, slight
    modifications to it are expected, most notably the addition of solar
    panels because it will have to operate unattended for a month or more.
    Any other modifications must fall within the talent/skill of a typical
    electronics amateur and cannot be something that could compromise the
    reliability of the unit.

    The 'no government permits' requirement is because the user will want
    to practice with it extensively before putting it to actual use, and
    they cannot afford having their name on file anywhere. (The wattage
    will have to be greatly reduced for such practice runs -- the idea is
    just to work out any bugs in setting it up and learning the quirks of
    the receiver.)

    Obviously, GPS would be ideal, but this is for use where there are no

    I thought there must be some military surplus radios, pre-packaged
    units for HAM field days, or other such things, but I cannot find
    anything that is close to the requirements of utter reliability, ease
    of use, and not needing extensive modifications.

    Does anyone know of something applicable?

    Any help appreciated.
  2. Jamie

    Jamie Guest

    Not to sound suspicious or anything, but it appears that you're
    trying to set up some drop or target points? What kind of business are
    you trying to get into where you can't have any one know about it
    and thus make it so the post can be abandon.

    Should we really take you seriously or what?

    I can tell you what I think it is but I won't.
  3. He is only trying to write some science fiction but wants to make it half

  4. Wildepad

    Wildepad Guest

    As I said, this is for a science fiction story.

    The basic premise is that a person is able to travel to parallel
    universes. In those universes which are so closely parallel that an
    'Earth' exists, a high percentage of the planets will be uninhabited.
    The protag wants to explore these as much as possible, but needs a
    reliable way to find their way back to the entry point so they can
    come home.

    Compasses can be unreliable (iron deposits can throw them off),
    inertial navigation is out of the question (the units are too big to
    carry by hand), and celestial navigation requires expertise.

    Except for its limited range, a radio system seems ideal.

    There are two main reasons for wanting to avoid anything in writing --
    first, for someone not especially interested in being a HAM, it would
    be long and difficult to learn enough to get the license required for
    most permits.

    second, there are five major fields which a person has to dip into in
    order to explore such a world and/or exploit anything they find. For
    two of those fields, it is impossible to not leave traces behind of
    your activity (unless you want to do things illegally). By keeping
    your name out of the other three fields, you won't be found by a
    cross-referencing search of all applicable databases, so overzealous
    government regulators, hijackers, blackmailers, etc. etc. etc. won't
    suspect what you're doing.

    IF I was interested in setting up drop points, GPS is easy, cheap,
    reliable, and perfectly stealthy.

    IF I was interested in setting up target points, instead of placing a
    trailer-mounted unit or other large package on the site, I'd just lay
    out the explosives when I'm there.
  5. Guiding something to it is much easier than the reverse. You have much of
    the high frequency end of the radio spectrum to use. Any transmitter can be
    detected and the location pinned down using receivers with directional
    You can probably build a suitable transmitter in a device not much bigger
    than a matchbox.

    Google tracking devices and search through simple electronic circuits. Look
    for devices which help the owner to find his model aeroplane. Just beef it
    up a wee bit.

  6. Wildepad

    Wildepad Guest

    I picture it as 'fox-and-hound' on a larger scale. The problem I'm
    having is finding something that will work over a large distance.
    That's the kind of thing I need, but my protagonist isn't into
    electronics, at least not enough to feel confident building something
    that his life might depend upon. (I hate it when the main character
    "just happens" to be an expert in absoutely every field they

    Asking someone to build it for him would raise questions (what would
    you think if someone asked you to make such a thing and then hemmed
    and hawed when you asked what they wanted it for?).

    So I'm stuck with either finding something off-the-shelf or figuring
    out some other way for him to find his way back to his starting point
    from up to 100 miles away in uncharted territory where he might not be
    able to retrace his route.

    A writer has to get this sort of thing right because the readers won't
    have the required suspension of disbelief for the big issues if
    there's an obvious mistake in the rw stuff.

  7. Suzy

    Suzy Guest


  8. Wildepad

    Wildepad Guest

    All sorts of things can happen, from engine failure to getting stuck.
    Because that gets your name put in databases and lets others know what
    you're doing which, while not technically illegal, can open you up to
    all sorts of regulations and/or hijacking, blackmail, etc.
  9. Rich Grise

    Rich Grise Guest

    Shop boat and airplane stores and clubs and such, and ask for "survival
    beacons" or the like.

    Good Luck!
  10. Rich Grise

    Rich Grise Guest

  11. Rich Grise

    Rich Grise Guest

    Hope This Helps!
  12. Rich Grise

    Rich Grise Guest

    Then you need some entirely new technology, to go hand-in-hand with
    whatever gets him from one parallel universe to the next - if radio
    waves could do that, we'd be swamped with cross-dimensional interference
    pretty much 24/7.

    Is he the only one with this ability, or is he a member of some
    organization; is it a secret, or general knowledge? If he's an agent,
    and the organization he's working for is using it for nefarious
    purposes, then just give him a little James-Bondesque tracker, which
    uses the same principles as the cross-dimensional portal, which you
    don't have to explain anyway.

    If he's a rogue, and wants his own tracker that's safe from them,
    then either he or an accomplice needs to be McGuffin, or whatever
    that guy's name was that can make an Enigma out of bottle caps. ;-)
    (or a mnemonic memory device from stone axes and animal skins. ;-) )

    I'm kinda partial to parallel universe stories - wanna collaborate
    on "Star Trek: Empire" with me? It starts right when Zefram shoots
    the Vulcan scout, and they strip the ship, and form the Empire, and
    all the stories that can arise from that. :)

    Good Luck!
  13. Wildepad

    Wildepad Guest

    Thanks . . . but :(

    I should have mentioned that I thought of that sort of thing (focusing
    mainly on the beacons used in light planes because they seem to have
    the longest range).

    The problem is that they have a small transmitter and the receiver
    uses a large directional antenna, which is exactly the reverse of what
    is needed in this scenario.

    Also, part of the backstory is how the protag practices with all the
    equipment, and I don't know how the authorities would react to your
    setting off such beacons dozens of times when no one is actually in

  14. Wildepad

    Wildepad Guest

    Um, no. Hardware generally falls into two categories:

    1) invisible in context (because of generations of blasters and ray
    guns, ST's phasers were readily accepted as just part of the scenery).

    2) so crucial that their method/construction/operating principles must
    be explained in detail (a hazardous prospect because a single error in
    theory or mechanics will ruin the story for a reader).

    (Ever read any 19th Century sf which contained rockets? The need for
    showing that such things could be real sometimes resulted in augers
    feeding gunpowder into the rocket motor.)

    If the protag uses gosh-wow tech, it falls into the second category,
    creating a lot more work and opening many pitfalls. But a radio
    direction finder is familiar to almost everyone and only needs a
    mention that it's there.

    In this particular case, it gets a bit of time center stage because
    gathering the necessary gear without raising anyone's suspicions is an
    important part of the story.


    This is set in the very-near-future. For a variety of reasons, the
    government maintains strict control over the use of the technology,
    and it is reaping the benefits of being able to sell/assign access to
    useful worlds.

    As per human nature, a black market forms. Here, this takes the form
    of a series of people/groups who each do a specific thing.

    Someone with a full-rigged-finder in a secure lab opens a microscopic
    hole to a parallel universe. They then sell those coordinates (which
    fill a flash drive). The value is determined by whether the connection
    is energy positive (such as opening into the middle of a sun),
    negative (the vacuum of space), or neutral (either solid or
    significant gas, such as found if there is a planet at the site).

    People who buy the neutrals open a slightly larger hole and take
    samples. Their customers pay varying amounts according to whether
    there is ore that can be mined, valuable gases which can be pumped
    out, etc.

    This protagonist buys coordinates that open on or near the surface of
    a world with an Earth-like atmosphere without any trace of organic
    compounds. He collects samples over as wide an area as possible, but
    his main contribution is surviving a week on that world, which shows
    that it is relatively harmless. (He's basically a value-added

    He was once part of a team, but they disbanded when they made an
    incredibly valuable find which let the powers-that-be in the group
    retire comfortably and left the grunts (like him) to shift for
    themselves. Most joined other teams, but he decided to strike out on
    his own.

    How the portal works needs no description because he doesn't know --
    he just rents time on an illicit machine owned and operated by someone
    else in the black market.
    In my experience, collaborations never work out.
    And since I have no idea what that means, I'm obviously not the person
    you want writing it with you! :)
  15. David Harmon

    David Harmon Guest

    On Thu, 25 Oct 2007 21:29:18 -0500 in sci.electronics.basics, Wildepad
    In the USA there are no permits required to purchase amateur radio
    equipment; only to operate it. And the basic technician license is
    pretty easy anyway.
  16. Wildepad

    Wildepad Guest

    Maybe it's easy for you. It sure ain't for some of us. :)

    I've been messing around with electronics for about 50 years. (When I
    started, it was all vacuum tubes and selenium rectifiers, with some
    rumors about doped crystals.)

    I've designed and built many small circuits (power supplies,
    'gameshow' buttons, interface to drive a stepper from a Centronics
    port, etc.). Nothing major, and no rf, but I sort of know my way

    When they dropped the Morse requirement for a license, I decided to
    look into it and got a sample test. I didn't understand what half the
    questions meant, and in those portions that I sort-of knew what they
    were talking about, I had no idea how to figure out the answer.

    I think it has to be one of those things you're interested in learning
    before you have a hope of getting the hang of it enough to pass the
  17. Martin Blume

    Martin Blume Guest

    Why not assume that a gadget has been invented that allows
    celestial navigation? You take a "CNAV" gadget (size of a
    GPS receiver), point it at the sky (ok, you need visibility),
    it takes a snapshot of the sky, correlates the stars with
    its almanac (you might have to feed in correct local time
    beforehand) and after some calculation spits out your local
    It might even be possible to do interstellar locationing.

    The rest is left as an exercise to the reader.

  18. Jamie

    Jamie Guest

    that's my question, "WHY" :)

    sounds like a way to innocently acquire information.

    I've been around far to long to say so otherwise.
    oh well.
  19. Suzy

    Suzy Guest

    Innocently? Sounds the opposite to me...
  20. Jamie

    Jamie Guest

    Well, make it appear that way:)
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day