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DIY Texting System For Really Underground Radio 98

Posted by timothy
from the nitpickers-will-come-out-of-their-caves-now dept.
Gulthek writes "Sixteen-year-old Alexander Kendrick has created a device that allows texting and other data transfer from almost 1000 feet underground. The tech could allow rapid emergency communication with the surface and opens the potential for scientific measurements without the need to continually visit (and disturb) the cave environment." There's some kvetching in the NPR story's comments that it's not the first use of cave radios, but that seems to miss the point.
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DIY Texting System For Really Underground Radio

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  • I guess Mom's basement goes really deep underground for this guy. Perfect technology for nerds everywhere! Why risk your pasty white skin getting outdoors to text?

  • by Anonymous Coward on Sunday January 31, 2010 @05:31PM (#30973984)

    This doesn't just apply to caving, it should work as well for mining no? Range shouldn't be an issue since if it uses radio then relays should be feasible.

    • Also submarine communications. The trouble is that the bandwidth is very very low.

      • Re: (Score:3, Insightful)

        by Darkness404 (1287218)
        Even with low bandwidth, a simple message of "Hey, I'm still alive down here, send help" shouldn't be too hard.
        • Re: (Score:3, Funny)

          by goldaryn (834427)

          Even with low bandwidth, a simple message of "Hey, I'm still alive down here, send help" shouldn't be too hard.

          That's what she said.

          Yes, my "bandwidth" is "low"

      • Re: (Score:3, Interesting)

        The Navy shore VLF/LF transmitter facilities transmit a 50 baud submarine command and control broadcast which is the backbone of the submarine broadcast system.

        More at http://www.fas.org/man/dod-101/navy/docs/scmp/part07.htm [fas.org]

    • Re: (Score:3, Interesting)

      by SaffronMiner (973257)
      No one has yet answered the Coal Mining Location Challenge: http://www.wearablesmartsensors.com/location_challenge.html [wearablesmartsensors.com] The is a much harder problem to solve than most people think, as explained at the link. The first thought is always "Use GPS". GPS does not work underground... etc. Range is an issue because Coal absorbs most radio waves. There are also limitations are power due to Intrinsic Safety Regulations.
      • Well, if more power is the answer, then change the regulations. Saying "regulations are the limit" seems weird.
        • Re: (Score:3, Informative)

          by solafide (845228)
          There's this thing called marcasite. It is often found with coal deposits, and is extremely flammable at temperature/pressure similar to that at the Earth's surface. Guess what a radio wave potentially exciting marcasite because it's overpowered will do --- it'll set the marcasite on fire, and as a result the whole coal bed. It's _intrinsic_ to coal mining, it's like breaking the gravitational laws --- you shouldn't try it.
          • OK, then the reason for low power is that it's dangerous, not because there is a regulation. I was just saying, the reason given originally for not using more power was "due to regulations."
            • Re: (Score:3, Interesting)

              by RockDoctor (15477)

              OK, then the reason for low power is that it's dangerous, not because there is a regulation.

              This may come as a shock, but some regulations are actually based on chemical reality. In this case, the purpose of "IS" designs of sensors, communication systems, etc, is to restrict the amount of energy in a hazardous area to below the amount that can produce a spark in an explosive hydrogen-air mixture. (I can't remember if it's at LEL or UEL, but WTF - it's still around 20 micro-Joules if I recall correctly). Sys

      • No one has yet answered the Coal Mining Location Challenge: http://www.wearablesmartsensors.com/location_challenge.html [wearablesmartsensors.com]

        I doubt anyone has really tried. The 'challenge' is on an obscure website, the 'challenger' cannot clearly be indentified, and the bits about 'pseudo science merely being science a few years ahead of the mainstream' are just weird.

  • by stox (131684) on Sunday January 31, 2010 @05:38PM (#30974074) Homepage

    Reduce your bit rate to a few bits per second, even fractional bits per second, and you will be amazed at how far you can get a signal with a minimum of power.

  • by JoshuaZ (1134087) on Sunday January 31, 2010 @05:45PM (#30974154) Homepage
    The article also talks about how this could be used by scientists who are investigating or monitoring life in caves and that this could be used to help find useful substances being made by life in the caves. From the article:

    But scientists think one of the biggest threats to this emerging source of antibiotics is actually the scientists themselves. In fact, researchers believe the more they visit a cave, the less likely they are to find antibiotics. People contaminate the sensitive cave environment just by being there. Northup thinks that by connecting data recorders to Kendrick's radio, scientists could remotely transmit information about the cave environment. "So a cave radio that allows you to beam data to the surface rather than visiting it in person can be extremely valuable," she says. "It could save the cave."

    Frankly, this doesn't seem that likely since to check if something is a useful antibiotic it needs to be tested against actual cultures generally. However, this does have serious potential of helping and of increasing our knowledge base. General medical knowledge and more anti-biotics will likely save far more lives than using the technology just to rescue people who occasionally get trapped in caves.

    • by Genda (560240)

      Actually you could do "bio-assays on a chip", style testing, and simply send back the results of those tests... even pass no-pass tests could be very useful, at which point your robot could take a few dozen well chosen samples back up top for further analysis. Such assays could allow you to do hundreds or even thousands of simple tests, and you could use a relatively small robot (or a robot with great ability to move through small spaces like a snake-bot) so your access to places people can't even go, could

  • by Jerry (6400) on Sunday January 31, 2010 @05:47PM (#30974168)

    I recall reading a story a few years ago about some protesters at Berkely using audio amplifiers to transmit information between their various members and groups. They'd attach the ground lead of the audio output of a 200 watt audio amp to a 10-15' rod pounded into the ground. The positive lead was attached to another, shorter rod, pounded into the ground several feet away. To recieve, they'd switch the wires from the ouput to the input of the audio amp. The claim was that they could send voice as an electrical wave several miles. Don't know how true the story is, but it sounds like it might work.

    In central Nebraska, not far from Silver Creek, is a "Survivable Low Frequency Communications System" The wiki writes about it: http://en.wikipedia.org/wiki/Survivable_Low_Frequency_Communications_System/>
    "SLFCS single channel, receive only capability is provided at ICBM launch control centers. The single channel operates between 14 kHz and 60 kHz to receive commands from remotely located Combat Operations Center - Transmit/Receive (T/R) sites; this low frequency range is slightly affected by nuclear blasts.". The signal travels along and underneath the ground, i.e., Ground Wave propagation. Because the frequency was close the the 60 Hz power line frequency the two 1 KHz side tones were used to track power line faults.

    When I drove by the Sliver Creek antenna and tuned my radio below 550 Khz I could find a hetrodyne signal and listen to the characters being transmitted in 5X5 blocks of characters.

  • Finally (Score:5, Informative)

    by Junior J. Junior III (192702) on Sunday January 31, 2010 @05:51PM (#30974230) Homepage

    No more out of range problems while I'm in my mom's basement.

  • Cave Rescue (Score:3, Informative)

    by HarleyCanuck (616646) on Sunday January 31, 2010 @05:54PM (#30974270)
    "In a 1991 New Mexico cave rescue, it took 170 people four days to save a woman with a broken leg. The rescue team had to lay miles of telephone line in order to stay in touch with the surface." "If they'd had Kendrick's radio, the rescue time may have been cut in half." When we go caving, especially a new one, or a rescue, Who wastes time laying phone wire? Teams are two, each with a different colour string with a wire core for added strength. This way we can follow different pipes simultaneously if its a complex cave. If two can get them out we do. Otherwise one stays one goes back. With all the gear we have who wants to be carrying all this stuff. If it can be made smaller the better. I guess my point is more about the Mexico rescue thing. Cool Idea kid!
    • Re:Cave Rescue (Score:5, Informative)

      by Anonymous Coward on Sunday January 31, 2010 @06:35PM (#30974650)

      I do cave rescue, so I have some insights.

      The first problem is that unless encrypted, radio communications are not secure. We don't necessarily want the press snooping in on radio chatter, which might include things like if the patient has died- then it shows up on the TV news before the family finds out in a less public fashion. That's not very popular with rescuers.

      The second problem is that communications aren't always 100% in this fashion; based on the cave radio work that I've been part of, it can be pretty sketchy. We're doing the same things as Alexander- and he's doing great work, no argument- but it's not exactly new stuff. Hard-wire communications aren't always 100%, either, but they tend to be more reliable. Maybe radio will exceed that someday.

      The Emily Mobely rescue would probably have taken about 100 hours with radio, same as it did with hard-wire communications. She was in a bad spot when she broke her leg, and Lech is a technically challenging cave- long hauls without a lot of space to work, that kind of thing. Because of Emily, people who have been injured in Lech have "self-rescued." Only a severe, debilitating accident that immobilized a patient would be cause for such a large, intensive rescue as hers.

      • You've been in Lechuguilla Cave? That's fantastic and I'm jealous!

        For those who don't know, a lot of the footage from Planet Earth: Caves was shot there. Here's a clip [youtube.com]. It is, I think, the deepest known cave in the US and has some completely unique rock formations. Unlike most limestone caves, this one was carved from the bottom up by sulfuric acid. Due to the delicacy of the cave environment, the Planet Earth crew is probably the last film crew to be allowed access. They did a great job of showing of

  • by westlake (615356) on Sunday January 31, 2010 @06:26PM (#30974556)

    Developed by Los Alamos National Laboratory, the Through-The-Earth Communication system proved capable of sending two-way, very-low-frequency (VLF) voice signals from the surface of the mine to depths exceeding 300 feet at the experimental mine operated by the National Institute for Occupational Safety and Health (NIOSH).

    The Through-The-Earth Communication system was developed for the U.S. Department of Energy at Los Alamos National Laboratory's Superconductivity Technology Center with a development team led by David Reagor. The technology has also earned a prestigious R&D 100 Award from R&D magazine.

    The system uses VLF electromagnetic radiation in the range of 3 to 30 kilohertz (kHz) and digital audio compression to transmit wireless voice and data signals through the earth. Materials that block higher radio frequency (RF) signals, such as rock, concrete, metal, and high-density ore bodies, do not restrict its signal

    Incorporating Sprint/Nextel i325 mobile phones, supported by Raytheon's JPS Communications ACU 1000 cross-band repeaters, the Through-The-Earth Communication system demonstrated its capabilities in the Lake Lynn Mine, which is composed of several long tunnels used for mine safety experiments. The mine consists of nonflammable limestone with a tunnel height of about 10 feet and an overburden of up to 370 feet. Test Of Through-The-Earth Communication System Exceeds Expectations [wirelessne...online.com] [August 2007]

    VLF appeals to radio hobbyists because of its exotic associations with both natural science and submarine warfare. To get started all you really need is a PC and a home-made antenna. Radio Waves Below 22 Hz [www.vlf.it]

  • by alanw (1822) <alan@wylie.me.uk> on Sunday January 31, 2010 @06:33PM (#30974622) Homepage

    for half an hour with a transmitter waiting for my friends on the surface to radio-locate the position on the surface vertically above me.

    The transmitter fits in a 6 inch diameter tube - you'd never get an antenna like the one in the photo down a Yorkshire cave. The one used on the surface is much bigger, though.

    The next project is to produce a cheap transmitter that a cave diver can carry into an aven and leave (they don't want to have to hang around), in the hope that once located a dig can be done from the surface directly above.

    Here's a links to a UK cave radio web site
    http://caves.org.uk/radio/ [caves.org.uk]

    • I agree, it seems way too big and unwieldy to go caving with. Especially for UK and Alpine caving. Something like the System Nicola cave radio would be better. It's small, lightweight and fits into a small peli case, making it perfect for caving and cave diving. Although, I'm not sure if they're in production yet. Here's the only site I could find with information on it (although it does get a bit technical as it's aimed for DIY hobbyists): http://naylorgr.perso.cegetel.net/cave_radio/ [cegetel.net]
      • The System Nicola Mk 2 has been in operation for a good many years in the south of France, and now the designer, Graham Naylor, is pressing on with a completely digital version, the Mk3. UK Cave Rescue Teams have been using the Heyphone [bcra.org.uk] since 2001. In 2004, Beat Heeb designed [bcra.org.uk] a mobile phone sized device for sending and receiving text messages underground. Both the Nicola Mk 2 and the "mobile texter" have ranges of ~1000m, I can't remember what the operating range of the Heyphone is.
    • by Dare nMc (468959)

      you'd never get an antenna like the one in the photo down a Yorkshire cave.

      FYI the antenna as transported was several short sections of PVC and a roll of wire. I have a hard time imaging a cave that is navigable by people that couldn't somehow shove say 1 meter sections of PVC into. If your saying the caves never expands to a size greater than a 2m diameter cube, then I agree they couldn't set it up.

      • by alanw (1822)

        Whilst there are places which open up, the part of the cave we wanted to locate was a lot less than 2m wide and high.

  • so this is the bin laden comm system?

  • by SuperBanana (662181) on Sunday January 31, 2010 @06:48PM (#30974758)
    Well, what is the point, then?

    VLF systems have been in use for decades to communicate with the US Submarine fleet, not because of interference, but because it passes through just about everything and has a very, very wide propagation. Unfortunately, the power levels are so high that people wonder/suspect it's causing nature / health problems for nearby residents.

    I mean for fucks' sakes, this stuff was in use by the German navy during WW2- 70 years ago. All this kid did was apply the obvious, and apparently, it's so obvious, someone thought of it 40 years ago. More info:

    http://en.wikipedia.org/wiki/Very_low_frequency

    Also, the kid didn't implement any sort of retransmission or error correction. That makes it pretty useless for both emergencies (imagine: "person has 3 hours to live" instead of "30 hours") and scientific data collection. It's also pretty standard these days.

    • by gandhi_2 (1108023)

      the kid didn't implement any sort of retransmission or error correction

      No kidding, if only there was some sort of layered protocol scheme whereby some facilities could be implemented at various other layers.

    • I mean for fucks' sakes, this stuff was in use by the German navy during WW2- 70 years ago. All this kid did was apply the obvious, and apparently, it's so obvious, someone thought of it 40 years ago.

      This stuff was used in World War One:

      http://www.rexresearch.com/rogers/1rogers.htm [rexresearch.com]

      James H. ROGERS

      Underground & Underwater Radio

      ( Static-free Reception & Transmission Underwater & Underground )

  • by Like2Byte (542992) <Like2Byte AT yahoo DOT com> on Sunday January 31, 2010 @07:26PM (#30975068) Homepage

    First. I applaud this guy for making such a neat device. Listening to the story break on NPR this morning was rather captivating. The reporter made the device sound relatively small - something able to fit easily within a single cave-bag after disassembly. After seeing the antenna array, though, I thought my eyes would pop out of my head. There is no *way* a group of cavers are going to carry this contraption around *as it is*. It is certainly a prototype and the device certainly has merit but, for the sake of the device and the caver(s) carrying it, it is hoped (at least by me) that it becomes a lot smaller and still able to transmit/receive with the surface counterpart.

    You see, a device as large as the one in the pictures on the webpage would be unwieldy in many, if not most, caves in the US as most US caves are not walking passage. In its current form it would suffer a lot of abuse and probably become submerged in water, covered in cave mud, bumped, sat on, kinked, bent, folded, dropped, hoisted, scraped and buffeted from a normal days wear and tear. If the antenna wire itself became broken trouble would certainly ensue. So, I don't see the current form of cave rescue going away any time soon. (The cave-trip leader has a designated person that did NOT go on the cave trip to call by a certain time. If the trip leader has not called that person by that time a cave rescue is supposed to be carried out.)

    Don't get me wrong - this is a very cave-worthy pursuit and many a caver would feel better about having this technology along for the trip - as long as the equipment could withstand the journey. Otherwise, it's just more dead weight.

    Second. For the story itself - caving is not 'relatively safe.' It's more along the lines of relatively dangerous. Why? Anyone entering a cave with the attitude of 'relatively safe' is bound to get hurt. Very recently there have been people who went out for a day of caving and came back sans one member. See this story [cbs5.com]

    I didn't know this guy but it seems arrogance killed him. Hate me for it if you have to but he went into a passage where 2 other people had to be rescued from years earlier. It's shameful that the cave owners/grotto overseeing the cave didn't have the foresight or fortitude to prevent future tragedies by closing that passage or making the cavers sign a form detailing that particular passage as off-limits. He died a slow death as hypothermia set in while he was upside down in a passage. He was supposed to be experienced. I heard about his story while he was still alive and I prayed that he could hold on long enough for a solution to extricate him could be found. I'm heartbroken and angry for his needless death.

    Thirdly. One part of the radio broadcast that this story didn't relay is a story of the famous (or is it infamous) rescue of Emily Davis Mobley from Lechuguilla Cave very near Carlsbad, New Mexico. I think the broadcast mentioned that this (the Lechuguilla cave rescue) was the reason why he invented this device. (I remind you to see the above paragraph on caving being relatively safe. Still think so?)

    You Tube of the rescue: http://www.youtube.com/watch?v=J7I7bXcSWK8 [youtube.com]
    Wikipedia Entry: http://en.wikipedia.org/wiki/Cave_rescue [wikipedia.org]

    Fourth. If you want to know more about caving visit Emily's website: http://www.speleobooks.com/ [speleobooks.com]

    Finally: If you still don't believe me that caving is dangerous just you try cave diving. Near 100% fatality rate where 'accidents' have occurred. The rule of thumb is is something goes wrong while cave diving - you have two minutes to live.

    Here's the official website for caving accidents in the Americas - http://www.caves.org/pub/aca/ [caves.org]

    FYI, There's NO FN WAY you'd get me to cave dive.

    • by drinkypoo (153816)

      I'm heartbroken and angry for his needless death.

      Angry I can understand; what an inconvenience for the rest of you! But heartbroken? This guy is a Darwin award nominee at best.

    • caving is relatively safe

      (sorry, couldn't resist)

      my dad was an avid spelunker before i was born. thank god/darwin he kept the relative danger to a minimum, or i wouldn't be here

    • by jc79 (1683494)

      I didn't know this guy but it seems arrogance killed him. Hate me for it if you have to but he went into a passage where 2 other people had to be rescued from years earlier. It's shameful that the cave owners/grotto overseeing the cave didn't have the foresight or fortitude to prevent future tragedies by closing that passage or making the cavers sign a form detailing that particular passage as off-limits

      I'm a professional outdoor activities instructor, and I've had friends who've died while participating recreationally in the sports they love. It's an accepted part of what we do. Surely it's up to an individual to assess the risks themselves and make judgements on what they consider acceptable. Why should the cave owners be considered responsible for someone's safety? "Volenti non fit injuria" - ie if you know the risks and do it anyway, you've only yourself to blame when you get hurt..

      I'm not a caver,. bu

      • by Like2Byte (542992)

        You know. That's a good perspective and one I take at whatever I do.

        This entire discussion pertains to 'wild caves' - not commercial caves.

        Caves in the US are largely kept 'under wraps' - cavers don't discuss caves with non-cavers for fear of someone attempting to spelunk while not having a clue as to what they are doing. How it works in most grottos in the US is that the new caver comes to a few meetings so the group can gauge whether or not the new guy (or gal) is simply someone looking for thrills or to

        • by jc79 (1683494)

          Thanks, that's really interesting.

          In Scotland, the legislation allowing for access to open land (which includes caves) specifically absolves the landowner of liability in the case of a person coming to harm by a natural hazard - otherwise every mountain and cliff would have to have warning signs along it.

          I'm pretty sure the law in England and Wales has similar provisions, although access to land is not a right as it is in Scotland. It seems daft to make the landowner responsible for persons outwith their co

    • by RockDoctor (15477)

      Very recently there have been people who went out for a day of caving and came back sans one member. See this story[http://cbs5.com/national/utah.cave.dealth.2.1337554.html]

      Hmmm, interesting. Another "Neil Moss" event. "Film," as the jargon-file entry goes, "at eleven." There are a number of "Neil Moss" concrete lumps scattered through the caves of Britain and I would safely assume Europe too. That America has them too is no surprise. One of my fellow cave-diving trainees made the mistake of bringing some s

      • by Like2Byte (542992)

        Being a little more precise, I think that you're hearing the darkness beckon, and you're about to go from stage 2 to stage 3. Or you're trying to square your public claims of "hardness" with your fear of the darkness. Don't worry ; fear is rational ; no-one who matters will think the less of you for declining the opportunity (apart possibly from yourself). What people won't thank you for would be not getting proper training if you decide to start to bubble, as you sound enough a member of the caving fratern

        • by RockDoctor (15477)

          It's just the video I've seen of cave divers pushing their tanks through a squeeze makes me shiver.

          You don't do it on every dive. Not even every second dive, unless you're particularly masochistic [GRIN].
          But analyse : why do you find such scenes particularly disturbing? If you were doing the same manoeuvres with the same bottles (OK, yes they do add up to a small bomb ; but you've carried and set charges before, haven't you?) in the air, would that freak you? Of course not (that, by the way, is the reason t

  • Carrier Wave (Morse code) would be way more useful than packet for rescue work. The only issue is that the splunkers would need to learn it. CW is a simple on/off sequence. It travels far, and is understandable even with a noisy signal.
    • by ndege (12658)

      Carrier Wave (Morse code) would be way more useful than packet for rescue work. The only issue is that the splunkers would need to learn it. CW is a simple on/off sequence. It travels far, and is understandable even with a noisy signal.

      You might consider reading a bit about PSK31 packet [wikipedia.org] as it is much lower bandwidth than CW. The clear advantage of CW is that you can use a "transmitter" that doesn't require electronics. ie: a rock banging against another rock.

      I posted a comment with more detail on PSK31 earlier see here: http://tech.slashdot.org/comments.pl?sid=1531648&cid=30977832 [slashdot.org]

  • It looks like there's a need for an approach along the lines of RFC 2549 [faqs.org], but using chiropteran [wikipedia.org] rather than avian carriers. Assuming that they can be trained, the bandwidth will be higher and the weight and volume to be carried by both cavers and rescuers considerably less.

  • by BitZtream (692029) on Sunday January 31, 2010 @08:56PM (#30975960)

    Seriously.

    If you're leaving a sensor in a cave or mine to gather data, its going to be there a while. Take a spool of wire with you on the way in and just hard wire the thing for data and power.

    Wireless is rarely the right way to do things, especially stationary things.

    • by fotbr (855184)

      As long as the cable survives a mine fire, or a mine collapse, then running a cable is fine. If you can't guarantee the cable's survival, then wireless is probably the way to go.

  • Alexander didn't "invent" anything. It's been known for decades that VLF waves will penetrate where other, higher, frequencies won't.
     
    But VLF doesn't get used much in the real world because of it's low bandwidth, high power requirements, and the size and fragility of the antennas required.

    • by iamhassi (659463)
      That's what I was thinking. They've been doing wireless communication for almost as long as submarines has existed. I'm sure 1940's sciencists are rolling in their graves right now.

      The problem I heard with underground is that VLF required a very long cable. From what I heard submarines would let out a cable hundreds, sometimes thousands of yards long to commuicate. Maybe just 1,000 ft underground wouldn't need hundreds of yards but I'm sure it still needs a few dozen, far too much to carry down with
      • by fluffy99 (870997)

        The receiving antennas are not nearly that big for subs (maybe you're confusing them with the towed acoustic arrays?). In fact the receiving antenna for surface ships is generally under 10-meters in diameter. Its the transmitting antenna that has to be enormous.

        It appears this is basically using VLF using very directional antenna both in the mine and topside. Hence the reason for a large antenna that has to be assembled. This is also the major downfall as you need to accurately aim and locate both antenn

  • Each of end of the antenna is a 6 foot wides, geodesics sphere. The caver has to put it together to be able to comminucate with the surface. I guess its not that easy sending signals though solid rock, without a big antenna. Maybe they could make it smaller with a neutrino beam?

    ---

    Ham Radio [feeddistiller.com] Feed @ Feed Distiller [feeddistiller.com]

    • Methinks that antenna looks like the fabled Octoloop [www.vlf.it] (look about 3/4 down the page). Granted, it provides some useful antenna gain, but another disadvantage (in addition to its' large size), is that it has a very narrow beamwidth. This would restrict reception on the surface to a very specific location which would be hard to determine in a rescue situation if the rescueres don't know where the transmitter is located.

      None-the-less, there is probably some niche applications for this (fault monitoring?) and

      • Let me correct myself. The Octoloop has a very narrow _null_ (not beamwidth). In a recue situation, the rescuers on the surface could use the antenna's null to direction-find the transmitter.

  • > There's some kvetching in the NPR story's comments that it's not the first use of cave radios, but that seems to miss the point ..

    It is a valid point - not the first ues. It does demonstrate skill for a sixteen-year-old to be ables to design and construpt the device. An amalgam of VLF radio and a digital device. Communication underground has always been a problem. Leaky lines [ieee.org] are one such solution, either active or passive.

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