You will never be able to create a network using conventional seismometers with that kind of coverage, density, and price. But since the fiber optic seismic observatory began operation in September 2. Mexico. In one particularly revealing experiment, the underground array picked up signals from two small local earthquakes with magnitudes of 1. The fiber optic seismic observatory successfully detected the 8. Mexico on Sept. 8, 2. Credit Siyuan YuanStanfordThe fiber optic seismic observatory is just the first step toward developing a Bay Area wide seismic network, Biondi says, and there are still many hurdles to overcome, such as demonstrating that the array can operate on a city wide scale. The researchers will describe their findings in the journal The Leading Edge in December. A paper focused on their signal processing methods will appear in the January edition of IEEE Signal Processing Magazine. You can read the preliminary announcement here in the Futurity Newsletter. FYI if you like to follow technical and scientific developments, the Futurity Newsletter is published by a consortium of universities to cover all topics of university research. Its simply great. FOA Members And Instructors Working To Repair Hurricane Damage in Houston, Florida and Puerto Rico. Last month we showed photos from Houston, Texas showing the damage caused by the recent hurricane. Of course that was followed by another hurricane that destroyed part of the infrastructure in Florida and Puerto Rico. We heard from some of our FOA contacts that damage to the power grid control systems was massive and we were told that in one case fiber cable was laid along the ground to replace cable lost when towers were damaged, waiting for the towers to be repaired. Our instructors have been working to train new personnel needed for the massive amount of repair work. HTB160XHSVXXXXXhXpXXq6xXFXXXx/Military-Tactical-Fiber-Optic-Patch-Cord-Connector.jpg' alt='Fiber Optic Patch Cord Company Lighting' title='Fiber Optic Patch Cord Company Lighting' />FOA instructor Jorge Aponte sent us some photos of the damage in Puerto Rico, the area most damaged by the Hurricane Maria. Damage to utility poles. Even underground cable plant is not 1. The survival rate for cell towers in the hurricane was extremely low the green indicates towers that survived. If you are interested in helping in TX. FL or PR, check online job sites, local utilities or contact the FOA at infofoa. Is This The End Of Real Fiber Optic Standards In The USWe just returned from a TIA standards meeting, which as usual had a few surprises. During the meeting, we realized we may be nearing the end of real fiber optic standards in the US. It was predictable. In fact I predicted it in 2. TIA announced that they were merging the old FO 4 fiber optic standards committee into the TR 4. The merger occurred because the FO committees which had been meeting for over 2. Most of the important topics had been covered component specifications had been standardized and about 2. FOTPs fiber optic test procedures had been written. Attendance was down, only 3 active committees were left and no one asked including yours truly was willing to assume the chairmanship. Since the FO committees had been meeting at the same time and location with the TR 4. TR 4. 2 had ongoing work adding fiber to the structured cabling standards, making fiber part of the TR 4. Or did it When I heard the news, I sent emails to several members of both committees expressing my concern. One of my sarcastic comments was Who decided a fiber optic technology group that covers anything related to communications fiber optics gets stuffed into a premises cabling group run by copperheads JH email, June 3, 2. Im now saying I told you so. Almost a decade later, at the meeting in Las Vegas last month, I made the comment in one of the subcommittee meetings that the document we were discussing was an example of how TR 4. The first really important example of this was the adulteration of OFSTP 1. I helped write in the late 1. The new version of OFSTP 1. ISO document that was created as a vehicle to require encircled flux mode conditioning in the multimode standards. Rather than being about how to test the cable plant, the majority of the new standard was about encircled flux. You had to go all the way to the back to Annex A to learn how to actually test a cable plant. The updates of OFSTP 1. FOTP 1. 71, many of the fiber optic standards have been rewritten to support the latest version of TIA 5. The older fibers that are still in wide use like 6. OM1 and the early 5. OM2 are not now recognized in these standards, confusing to many users who still have these older fibers in use. We know because they call FOA asking us questions. We tell them their systems are no longer recognized by the current standards and they need to refer to earlier versions that applied to them. Within the US, Id guess less than 5 of all fiber applications are in structured cabling, probably only 5. In the committees, the majority of the attendees are from companies specializing in structured cabling. So whats happening is not surprising. Im still amazed by some of the stuff I see, especially coming out of international committees. For example at the Las Vegas meeting, an IEC document IEC TR 6. MPO connectors. Look at how this document defined a connector connector component consisting of two plugs mated together in an adapter, for the purpose of providing frequent optical interconnectiondisconnection of optical fibres or cables, between two cables, or a cable to an apparatusThe rest of the world would call this a connection as the committee agreed when I pointed it out. Perhaps it was lost in translation, but can anyone tell me how two plugs mated together in an adapter connects to an apparatus like a pluggable transceiver And then there is this definition light source power meter test system consisting of a light source LS, power meter PM and associated test cords used to measure the attenuation of installed cable plantThats also crazy reference test cords the ISO standards uses the term cords instead of cables are not considered part of the test equipment. There was more the document used back reflection an obsolete, incorrect term, reflectance and return loss interchangeably often in the same paragraph without defining any of the three terms. And what it purported to cover, testing MPOs, was incomplete and confusing. You are better off going to the FOA Guide page on MPOs http www. MPO. html which explains the issues in understandable language. We know these standards are written by manufacturers for manufacturers weve been told that many times by TR 4. Whats a userdesignercontractorinstaller to doFOA responded to this a few years ago, creating what we called 1 page standards, simple explanations of the test methods with clear drawings. Can a single page explain what is covered in a 3. Yes it can check them out. FOA Standards. JH Fiber Optics Used In Aerostat Tethers. Frequently asked questions on fiber optics. The Fiber Optic Association. Tech Topics Frequently Asked Questions The FAQs We get questions all the time, so we have started putting those we feel have general interest on this web page. As it grows larger, well index it for convenience. Heres more testing FAQs too. Looking for more informationTry the FOA Online Reference Guide or the Tech Topics index The Questions We Get Most Often Can you explain to me in simple terms what the difference in fiber optics and traditional copper cables We get this question so often, and it is such a complex issue, we created a whole web page to answer it Do signals really travel faster in fiber optics You know that sending communications at the speed of light means the speed of light in glass about 23 C, but you might be surprised to know that signals in UTP unshielded twisted pair cables like Cat 5e travel at about the same speed 23 C. Coax, meanwhile, has a faster NVP nominal velocity of propogation, about 0. C, due to its design. Fibers speed is not referring to the speed of the signal in the fiber, but the bandwidth potential of the fiber. Can you give me a definition of structured cablingStructured Cabling refers to a standardized cabling architecture, specified by EIATIA 5. US and ISO 1. 18. It uses twisted pair and fiber optic cables to create a standardized cabling system designed for telephones and LANs built by many manufacturers. The nomenclature here is even less precise. Vendors also refer to this as structured cabling, data voice cabling, low voltage cabling and limited energy cabling. What is a better way of communication,wire or fiber optics The telcos and CATV companies use fiber optics because of economics. Its greater bandwidth and lower attenuation allow longer distances and more channels voice or video per fiber pair. Typical fiber specs are more than 1. Try this for some more reading. Im a tech coordinator at a k 1. Depending on what you read and who you talk too and which way the wind is blowing, the decision on whether to wire CAT 5 or fiber is a toss upIn your opinion, which is more cost effective for a building that is trying to set up a solid switched backbone that will be usable for 5 1. Ive headed a school tech committee myself and work with local schools had kids in school locally both now in college and theyre asking the same question. Many are looking very seriously at fiber. Many schools are now wired or wiring with a fiber optic backbone and Cat 5 to the desktop. That will support Fast Ethernet, which will probably be good for 5 years. It requires local hubs which require conditioned power and UPSes, and the total cost is probably more than an all fiber network today or equal. WIth fiber, you get more potential bandwidth, but you also get rid of the hubs and all their additional needs, like power, space, management, etc, You can buy 1. Base SX NIC cards for jsut over 1. Gemflex www. gemflex. M Volition connectors which save on the cable plant. And you can upgrade at least to GB Ethernet. With copper, Im afraid you buy into a cable of the year club. The industry has already written off Cat 5, has been selling Cat 5. E extended which has finally become a standard, now is pushing Cat 6. A a year or more away from being standard and talking about Cat 7 The FOA Online Reference Guide has a complete section on cabling, fiber and copper, plus wireless. On General Fiber Optics. Can People On Omegle Hack Your Computer. What are some of the uses of. The biggest use is telephony, followed by CATV. LAN backbones, connecting hubs. Next is connecting remote. The building management and. EMI requirements. Fiber is not often used to the. Gigabit Ethernet will drive even more fiber into networks. UTP applications will be too difficult to install. Will intelligent buildings use fiber optics or copper wiring to carry voicedatavideo throughout the structure Both. Fiber will be used when the distances are longer than 9. Gigabit Ethernet. Most backbones will be fiber. Desktop connections to telecom closets will be copper for the near future, until network managers find out what a telecom closet really costs Phones will continue to use copper until we all go to voice over IP. Video CCTV uses fiber for distances over about 1. Can you please tell me what the difference between, d. B and d. Bm when you are trying to test fiber optic cable. Fiber optic power measurements are generally made in a log scale of decibells or d. B actually named after Alexander Graham Bell that has a scale of 1. B for every factor of 1. The equation is actually d. B1. 0 log power 1power 2 d. B is therefore a ratio measurement 1. B and 1. 00 times less is 2. B, etc. For ABSOLUTE measurements, you must have a reference point. If we use 1 milliwatt of power as our reference, our equation becomes d. B 1. 0 log power1 m. W So now 1 m. W is 0 d. B, 1. 0 m. W is 1. B, 0. 1 m. W is 1. B, etc. Heres more information on testing including d. B too. I need to be able to measure the true or useful power of a VCSEL Laser Diode. To do this, I believe I need to measure the Peak to Peak power the extinction ratio. All FO power meters measure average power. This is simply peak power diluted by duty cycle. If you know the duty cycle of the signal and the average power, you can calculate peak power as Avg pwrduty cycle. If you are measuring a signal with a clock of 5. Most high speed networks are sending random data, so the duty cycle can probably be assumed to be 5. Many systems have a test mode that transmits 5. I am confused by the resolution choices in fiber optic power meters. If accuracy is 0. B, then it doesnt seem worthwhile to have resolution out to the hundredths thousandths of a d. B, when accuracy is only in the tenths one decimal place. Resolution for power meters is an interesting subject. If you measure power, and the measurement is accurate as or as NIST prefers has a measurement uncertainty of 0. B, a measurement of 0. B 0. 2 d. B is confusing. The 11. 00 th d. B resolution is in fact meaningless. If the uncertainty was 0. B, a hundreth resolution would make sense. Now remember we are talking absolute power measurements, calibrated relative to NIST standards. If we are looking at loss measurements, things changed considerably. The loss of a LC connector, about 0. B, is measured relatively, eg. Bm to 1. 5. 1. 0, and the measurement uncertainty now has nothing to do with the absolute power levels, but the RELATIVE difference between the two readings. That difference is as precise as the linearity of the power meter better than 0. B and the uncertainty of the mating of the connectors a few hundreths too. So you certainly want a meter with 0. B resolution to test connectorsIf you are testing an installed cable plant with say 3 1. B loss, the uncertainty is probably 0. B, so 0. 1 d. B is adequate. If its a long haul network with 3. B loss, the uncertainty can be over 1 d. B, so 0. 1 d. B is much more than adequate. How do you classify fiber optic cable Broad question By NEC UL flame retardancy. By cable types tight bufferdistributionbreakoutloose tubeBy fiber types multimodesinglemodehybridWhether it has fiber and wire composite cableSee the cable section of our Online Reference Guide or Lennie Lightwave for more information. What type of fiber is required to run at gigabit speed Depends on how far you want to go. Plain old FDDI fiber 1. MHz km bandwidth 8.