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Communications Wireless Networking Hardware Science

Ham Operator Sets New Miles-Per-Watt World Record 403

Posted by timothy from the bend-it-like-an-ionospheric-layer dept.
DoctorPepper writes "A ham radio operator in New London, North Carolina correctly copied an 80 meter CW beacon in Wappingers Falls, New York, a distance of 546.8 miles. The kicker is, the beacon station, an Elecraft K1, was putting out 40.6 uW (40.6 millionths of a Watt) -- which works out to 13,467,980 miles per watt!"
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Ham Operator Sets New Miles-Per-Watt World Record More

Ham Operator Sets New Miles-Per-Watt World Record

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  • Even when it's horribly outmoded... (Score:5, Interesting)

    by fussili ( 720463 ) on Wednesday January 05, 2005 @07:03PM (#11269947)
    Ham Radio continues to excite. I think there's something romantic about it that draws geeks towards its coils - how else do you explain the way it has enthralled so many in its history? The venerable Woz is one. Can anyone else recall any Ham Radio enthusiasts who went onto bigger things in Tech?

  • errrr... (Score:4, Funny)

    by Capt'n Hector ( 650760 ) on Wednesday January 05, 2005 @07:04PM (#11269955)
    In english, please?
    • English: A loner geek geeked better than any other geek before him.
    • In english, please?

      I'll take a crack at it:

      Lyonay utray ealray eeksgay ivegay a atsray assray outabray isthray.

      That help?

  • Ham Geeks (Score:5, Interesting)

    by Mark_MF-WN ( 678030 ) on Wednesday January 05, 2005 @07:04PM (#11269959)
    Ham radio people are are truly the geeks' geeks. The mad-science of it all truly inspires.

    • Re:Ham Geeks (Score:3, Interesting)

      by Buzzygirl ( 846816 )
      I'm a female ham... and a rare breed, we are. Hams are often stereotyped as old, fat, geeky, hygenically-challenged white guys (actually, my one and only visit to a local hamfest somewhat confirmed this) but none of those traits describes me. Radio is old technology, but I have always found it fascinating, ever since my dad introduced me to the shortwave bands when I was a little kid. There was always something a bit magical about a signal traveling halfway around the world to be picked up on an old tube

  • Further applications? (Score:5, Funny)

    by IntelliTubbie ( 29947 ) on Wednesday January 05, 2005 @07:04PM (#11269962)
    So will this make it easier to bring Dennis Quaid back from the dead [imdb.com]?

    Cheers,
    IT

  • Previous record? (Score:4, Interesting)

    by UWC ( 664779 ) on Wednesday January 05, 2005 @07:05PM (#11269977)
    Does anyone know what the previous record was? I'm not at all familiar with hamming, though it strikes me as quite interesting based on this and the recent tsunami-related story (primarily the ensuing comments).

  • Ummmmm (Score:5, Funny)

    by Prince Vegeta SSJ4 ( 718736 ) on Wednesday January 05, 2005 @07:06PM (#11269981)
    Man A: A new record was set today

    Man B: what?

    Man A: 13,467,980 miles per watt

    Man B: What?

    Man A: Watt?

    Man B: What!?!?!?

    Man A: Watt!!!!

    Man B: Forget it, I'm not playing this stupid thing, go be an A$$.

  • HAM Geeks (Score:5, Funny)

    by Bender_ ( 179208 ) on Wednesday January 05, 2005 @07:06PM (#11269983) Journal
    omg.. after reading that article I got the feeling that there are people even more geeky than computer geeks.

    "I'm thrilled the record was set by an all-American team using all-American equipment." The Ten Tec receiver is manufactured in Severville, TN and the Elecraft transmitter is produced in California and offered as a kit.

    yes, so relevant...
    • Very relevant to those of us who decry the day IBM sold out it's PC Division to Great Wall Computers in China.

    • Re:HAM Geeks (Score:3, Informative)

      by harrkev ( 623093 )
      Actually, this IS kind of neat. Most of the ham market is owned by Japanese radios: Icom, Yaesu, and Kenwood. It IS neat using American gear.

      Plus, the Elecraft K1 is a kit. If you want one, you get a board, a metal box, and a bag full of parts. Some assembly required. For some people (like me), this is a feature, not a bug.

    • Re:HAM Geeks (Score:3, Interesting)

      by TheGavster ( 774657 )
      See, there's this association of amazing electronics coming from Japan. This goes to show that American stuff isn't dead. Yet.

      Now, who's for embargos on goods produced by underpaid workers? Let's bring the minimum wage to the developing world!
    • omg.. after reading that article I got the feeling that there are people even more geeky than computer geeks.

      Being a computer geek who works with a HAM geek... yea, there are people who make computer geeks look, well, hardly geeky at all by comparison. HAM radio operators often fit in that group. What's really shocking is that anything is still actually manufactured in the U.S...

  • Hmm.. check your math (Score:5, Insightful)

    by Ckwop ( 707653 ) * on Wednesday January 05, 2005 @07:06PM (#11269987) Homepage
    I don't think the math is right there. If it's a straight mast then the wave front will spread out radially.

    So increasing the power wouldn't give you a linear increase in distance like the OP seems to believe it would.

    Simon.
    • But the ratio between miles traveled and power used works out correctly.

      I am sure that the early records were set with more than a watt even though decreasing the wattage wouldnt have a linear effect.

    • Yes you are right. This does not scale, distance and attenuation do not have a 1:1 slope. Thus, one watt at a million miles would be unbelievably weak signal than one microwatt at one mile.

      -S

    • Re:Hmm.. check your math (Score:3, Insightful)

      by rsw ( 70577 )
      The correct way to do this is to distribute the radiated power over the surface of the sphere at the radius in question. Thus, one measures it in terms of power per square meter, i.e., field strength.
    • I don't think the measurement is provided as a predictor of how many watts you'll need to send a signal a given distance with the equipment; it's just a ratio normalized to one watt for the sake of comprehension.

    • Re:Hmm.. check your math (Score:5, Informative)

      by frdmfghtr ( 603968 ) on Wednesday January 05, 2005 @08:55PM (#11271051)
      Right...the power drops off as the square of the distance, when you are operating in the far field.

      The far field of an antenna starts at a point where the radiated wavefront is practically flat. One such measure of this distance is

      2* D^2
      R = ----------
      wavelength

      where D is the largest dimension of the antenna. With a satellite dish, this is the reflector diameter typically; with a monopole ("stick") antenna it is the antenna length. There are other measures that are also used to calculate the start of the far field, but I can't recall them now; I will say that whichever one yields the furthest distance is the thumbrule used.

      Your orientation to the radiating antenna also plays a role. A "stick" antenna (dipole or monopole) has more energy radiated perpendicular to the mast than along the mast axis. In free space with no reflections, you can stand at either end of a stick antenna and not receive squat, as long as you are in the far field. Thus, you must also consider the gain of your antenna in the direction of interest. A stick antenna has about 3dB gain perpendicular to it, and negative infinity gain along the antenna axis.

      The actual equation to get the power density Pr when distance r from the source is:

      Pt * Gt
      Pr = ----------
      4pi*r^2

      Pt = Power radiated
      Gt = Gain of your antenna

      That's why the change in power to distance isn't linear. May have been long-winded but I spent most of the afternoon doing power density calculations so it was fresh in my head.

  • Obligatory... (Score:3, Funny)

    by Anonymous Coward on Wednesday January 05, 2005 @07:07PM (#11269991)
    Watt did you say? Turn it up...

    Ohm my! That Hertz!

  • It is non-linear (Score:5, Informative)

    by frakir ( 760204 ) on Wednesday January 05, 2005 @07:08PM (#11270005)
    Even most directional antennas will not give you linear 'watt to distance' amplification.

    In worst case it is a power^1/3. So for 40 milliwatts to 1 watt amplification you'll get some 30x distance (at worst), but never 2500x, unless some wicked atmospheric conditions happen.
  • yeah? so watt?

  • Whiners. (Score:5, Insightful)

    by RobertB-DC ( 622190 ) * on Wednesday January 05, 2005 @07:09PM (#11270015) Homepage Journal
    From the comments at the article site:

    While the ability to receive a very weak signal is always interesting (and exciting for QRPP operators), converting results into "miles per watt" is an absolutely useless way to express results!!

    The whiner goes on to say:

    At 1.5 MHz data in CCIR Thirteenth Plenary Assembly (vol VI report 264-3 p 108) shows attenuation increases ~10 dB when path length goes from 500 km to 1000 km. Doubling skywave path length at 500 km when at 1.5 MHz increases loss 10dB, NOT 3 dB. Doubling distance again (same frequency) from 1000 km to 2000 km results in an additional ~15 db loss! 2000 km to 4000 km is about 22 dB more loss. This is based on measured data.

    While most of the numbers leave me with a blank look, one thing is clear: the poster missed the point. The accomplishment is cool because of the geek factor, not because it's going to lead to a new radio in your car. Therefore, the measurement of the achievement doesn't *have* to be "useful".
    • This doesnt have anything to do with whining, 15million km per watt is simply FALSE.
      Its a cool archivement, but you still shouldnt post bullshit claimes...
    • So, hows the sig to noise ratio thing going? ;~)

    • While most of the numbers leave me with a blank look, one thing is clear: the poster missed the point. The accomplishment is cool because of the geek factor, not because it's going to lead to a new radio in your car. Therefore, the measurement of the achievement doesn't *have* to be "useful".

      Would you feel the same way about someone bragging about their CPUs clock frequency? That's the same situation: getting excited about a practically useless measurement. Just as most computer geeks know that MHz is

  • According to the article, the receiving operator was using a 1,000 foot antenna. I'd be more impressed if the antenna were smaller.

  • Miles per Watt? (Score:5, Informative)

    by c++ ( 25427 ) on Wednesday January 05, 2005 @07:11PM (#11270046)
    This seems an odd way to compare accomplishments. If you use this metric, then you reach the false conclusion that doubling wattage doubles distance. Since signal strength deteriorates with distance squared, a better metric might be miles^2 per Watt.

    Example using round numbers. Philip transmits 10 miles using a 10W transmitter. Sally transmits 19 miles using a 20W transmitter. If you use miles per Watt to compare, it looks like Philip achieved better results, when in fact Sally did.
  • now we should realy start wearing the tinfoil hats

  • Yawn (Score:4, Funny)

    by codepunk ( 167897 ) on Wednesday January 05, 2005 @07:12PM (#11270053)
    My cell phone can talk around the world on it's itty
    bitty power output.

    • Re:Yawn (Score:5, Informative)

      by chill ( 34294 ) on Wednesday January 05, 2005 @07:27PM (#11270208) Journal
      My cell phone can talk around the world on it's itty bitty power output.

      No, it can't. That is why there are those little bars showing signal strength. You're lucky the newer digital units can get two miles to a tower (where it is then pumped thru an ATM link over a T-1 to the landline network).

      Funny, fine. But to whomever modded that post "Informative" needs to go back to school.

      -Charles
    • Yup. So could mine, until several of the cell towers around my place were blown down or knocked off the air by Charley's 180MPH gusts in August.

      If I had needed to, I could have sent messages back to my family simply by walking outside after the storm with my 2m handheld and checking in to the local message traffic net.

  • Why would you measure miles/watt? (Score:4, Informative)

    by exp(pi*sqrt(163)) ( 613870 ) on Wednesday January 05, 2005 @07:13PM (#11270070) Journal
    It's as sensible as measuring distance travelled/max acceleration of a car. There simply isn't a linear relationship between these things and so dividing one by the other doesn't give you anything interesting. If we start dividing random variables by each other and reporting the result on /. we'd never get to read any interesting news.

  • power is 1 over r _squared_ (Score:5, Informative)

    by WillWare ( 11935 ) on Wednesday January 05, 2005 @07:15PM (#11270087) Homepage Journal
    40.6e-6 / (546.8 ** 2) = 1.35790386 × 10**-10

    The units here are watts per square mile. Your typical FM radio station has a range of maybe 50 miles and is running maybe 10 kwatts, so they're doing 4 watts per square mile. This guy is doing much better. My own power/distance record, back when I was active in ham radio, was 7000 miles on about 25 watts, or 5.10204082 × 10**-7 watts per square mile.

    You might wonder how it's remotely possible for there to be a gap of seven to ten orders of magnitude. Why aren't we bothered by FM radio stations on the other side of the world? There is a qualitative difference between the behavior of radio waves above and below about 30-50 MHz (the FM band starts at 88 MHz). Conditions permitting, the lower frequencies can refract in the ionosphere and come back down to earth along non-straight-line paths. That's why shortwave radio stations on other continents can be heard.

    • Um, i seem to work for a few 100kW @ 1500ft radio stations. The absolute local stations in BFE are maybe 10-20kW, but i guarentee there's stations out there who can be heard in places they really shouldn't be. (WLS-FM for instance is 175kW blasting the entire midwest) Believe me, height matters greatly.

  • Spread spectrum (Score:5, Interesting)

    by morcheeba ( 260908 ) on Wednesday January 05, 2005 @07:18PM (#11270114) Journal
    Commenting on his remarkable success, Bill said "I've spent 25 years on 80 & 160 listening to below noise level signals ..."

    Below noise signals sounds paradoxical, but people do it all the time. If you're in a noisy restaurant, you can pick out individual noises even though they are much quieter than everyone else. The key is that you have an idea of what you expect to hear - you generally know the tone of their voice, know what sounds make words, know what words make understandable sentences.

    Imagine if the signal had been spread-spectrum. Spread-spectrum signals are stealthy because, they to, can be recovered from below the noise floor. Basically, with an idea of what to expect, the receiver's processing can effectively raise the signal above the noise floor [maxim-ic.com]. Instead of sending short tones for each bit, a series of tones are sent for each bit (a chip) - one chip for zero, and a different chip for one. It's a lot easier process a sound and see which chip it sounds closer to than it is to see if one particular tone is there or not.

    So, in summary, this guy's brain played a lot in the reception to pick out a signal from the noise. I wonder if the next record will be set with a spread spectrum transmitted signal and a digital processing receiver.
  • I'm thinking that this is a case where less traffic in the Ham world of frequencies has made it easier to get more distance. It's easier to hear someone in a empty room than one full of yapping people.

    Anyone got any numbers on how crowded the frequency spectrum involved is, and how much it's changed.

  • Just to be a nitpicker... (Score:3, Informative)

    by RichDice ( 7079 ) on Wednesday January 05, 2005 @07:29PM (#11270235)
    What about the Voyager spacecraft? Signals from those are still being received, they're about 90 AU from Earth right now, and though (after around 3 minutes of looking) I couldn't find the watts they're putting into radio transmission, I did find that the whole spacecraft operates on 315 watts. (Or at least it did when it was at its full power -- which it isn't now.)

    For maximum pessimism, say that it's currently putting its maximum 315 watts into "phoning home" -- I work this out to 26.1 million miles per watt. (My guess is that realistically it's more like 1e3 times that.)

    Sorry HAM-guy, but Voyager still kicks yer butt.

    Cheers,
    Richard

    • Re:Just to be a nitpicker... (Score:4, Informative)

      by Gordonjcp ( 186804 ) on Wednesday January 05, 2005 @07:59PM (#11270515) Homepage
      Voyager uses (iirc) eight watts. Yup, eight. Twice as much as a CB radio. To put this in perspective, turn on your car's sidelights (not dim-dip, just the parking light bulbs). That's about eight watts of light. Now imagine how hard that would be to see from the far end of a supermarket car park (try this late at night when the big Asda on the edge of town is shut). Now imagine how hard that would be to see from a mile away.


      Now imagine how hard that is to see from 7 billion miles away.

  • Can I have this in libraries of congress per watt? Or diameters of earth per 21 gigawatts? (I think I messed up the reference.) Is miles per watt a useful scale? What does that mean?

    I think I know what watts are, I know what miles are, and I somewhat understand the concept of ham radios. I still don't understand a relationship between the three (maybe I'm being stupid).

    Anyone care to explain to the unwashed masses what this means?

  • 1000 Miles per watt award (Score:3, Interesting)

    by leighklotz ( 192300 ) on Wednesday January 05, 2005 @07:39PM (#11270333) Homepage
    The 1000 miles per watt award [qrparci.org] is fairly easy to get. I exceeded it twice recently, when I worked ES5MC in Estonia [wa5znu.org] from California with 4.5 watts with my Elecraft KX1 [elecraft.com] and a pack of AA batteries and a 28ft wire in a tree in central California, and OH9SCL in Santa Claus Land [wa5znu.org] (Rovaniemi Finland, news [mercurynews.com], news [nytimes.com]) with the same radio from a parking lot by the San Francisco Bay.

  • Shannon limit? (Score:3, Interesting)

    by Doc Ruby ( 173196 ) on Wednesday January 05, 2005 @07:49PM (#11270437) Homepage Journal
    Is there a theoretical maximum limit to how far a single bit can be propagated in 1.0 watt of laser power at, say, 1m wavelength? Photons don't seem to accelerate from their quantum ground state before emitting from an electron shell, so does their max-velocity travel consume any energy? Aren't the photons traveling in a spiral path around the axis of their direction, which consumes energy to move their tiny mass equivalence off their inertial path?

  • Ham Radio (Score:3, Interesting)

    by cantrade ( 125062 ) on Wednesday January 05, 2005 @07:59PM (#11270504)
    Yes it is out moded and full of old geezers that sit in their garages and talk to others like them. But I never cease to be amazed that I can sit at my meager station and with 25 watts talk to someone in Nome, AK or in the middle of the Indian Ocean. Nerdy and Geeky for sure but still totally interesting.

  • Obviously never heard of the inverse square law... (Score:3, Informative)

    by GrahamCox ( 741991 ) on Wednesday January 05, 2005 @08:12PM (#11270659) Homepage
    Miles per watt indeed! What tosh.
  • By my calculation, the true miles-per-Watt would "only" be about 16K miles, if the transmitter is omnidirectional, which would make its signal strenght decrease with distance-to-the-power-of-three: ((1/0.0000406)^(1/3))*546.8 (just over 15909) miles is the distance you could reach with one Watt, if 0.0000406 Watts gets you 546.8 miles.
    (of course, if it's a record using the dumb/linear way of calculating it, it's still a record when calculated the other way)

  • This is stupid (Score:4, Insightful)

    by KFury ( 19522 ) * on Wednesday January 05, 2005 @08:33PM (#11270848) Homepage
    'Miles per watt' is a stupid, meaningless metric. Since watts dissipate by the inverse square law, it's completely false to say that (for example) a an efficiency of 0.001 watts at one mile equates to 1 watt at 1000 miles.

    If I wanted to break this 'record' I would simply replicate the experiemnt from a distance of 273 miles (half the distance) where I could pick up the signal with 1/4th the required signal strength (inverse square law) and suddenly I have a 'record' of 26,935,960 miles per watt! Heck, if we put the transmitter on the same circuit board as the receiver I could create an 'efficiency' that would let me contact quasars with a hamster wheel.

    Bah.

  • Miles per watt? Get a unit. (Score:3, Interesting)

    by SETIGuy ( 33768 ) on Wednesday January 05, 2005 @09:48PM (#11271448) Homepage

    What kind of unit is miles per watt? I could see watt per square mile, or preferably watt per square meter.

    If 80 meter radiation penetrated the ionosphere, the detection at a range of 880 km would be about 5*10^-17 W/m^2. I'm fairly sure 80 meter bounces both from the ionosphere and the earth itself, which results in some amplification over the inverse square law value.

    In contrast the detection threshold for SETI@home is about 5*10^-25 W/m^2, or a factor of 100 million smaller.

  • In my amateur radio days (Score:4, Interesting)

    by Daath ( 225404 ) <(kd.redoc) (ta) (pl)> on Wednesday January 05, 2005 @11:37PM (#11272141) Homepage Journal
    In my amateur radio days, I was a very popular conversation - I had a small 5W radio, and I built my own di-polar antenna, I was in Nuuk (capital of Greenland), and I had conversations with southern Brazil, Japan and others - I talked to a lot of people in the UK, and they had trouble believing that I was in Greenland - They said that it sounded like I was in their back yard with a 50W radio ;)
    They were all VERY happy to receive my QSL-card ;)
    Oh, if anyone remember me, I was 45SR101 ;)

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