OTDRs - What Does An APC Connector Look Like?
Recently we sent some cables with APC connectors to Terry O'Malley, FOA Master Instructor who happens to be the originator of AT&T's OTDR training programs a long time ago. We wanted some traces of the APC connector joint to show you how these low reflectance connectors look. So here is a trace and a close up.
The marker shows the location of the connector.
Note the connection is hard to spot - virtually no reflectance and little loss. Let's look at the enlarged trace:
Now we can see more detail. It has just over 0.1dB loss and a very small reflectance peak. Considering the noise on the trace here, if you did not know this was a connection, you would probably think it's a splice. That's another reason to have good documentation.
What Is "THE COST OF CONNECTIVITY"
The Cost of Connectivity 2014 is an annual report by the Open Technology Insittute that examines the cost and speed of broadband Internet access in cities in the United States (U.S.) and abroad. Overall, the data that we have collected in the past three years demonstrates that the majority of U.S. cities surveyed lag behind their international peers, paying more money for slower Internet access. The report presents the 2014 Cost of Connectivity data, which was collected between July and September 2014.
The table below shows the ranking of cities around the world ranked by speed. Note that the gigabit leaders include Google fiber in KC and 3 municipalities (Chattanooga, Lafayette and Bristol) and the only traditional US service provider listed is Verizon with FiOS. Even high tech San Francisco only ranks 20th.
The report is full of data, graphs and analyses. It's worth a careful reading. Read the entire report here.
Notice AT&T is nowhere in this list.
AT&T has been using only DSL in most markets but have been claiming they will compete with Google Fiber and install FTTH in many areas in the US. But when President Obama publicly told the FCC to make "net neutrality" a priority, AT&T loudly announced they were putting all their plans for FTTH on hold until the net neutrality issue was settled. That action let to an interesting exchange in an interview by the Washington Post of Deputy U.S. CTO Alex Macgillivray, formerly a lawyer at Twitter and Google.
Washington Post: The CEO of AT&T this week said that the company will "pause" the rollout of broadband fiber in 100 cities in the United States because of the ongoing net neutrality debate.
Macgillivray: I just came from business. And it's not every day that a business says that they're not going to do something that's good for their customers. That's a strong statement.
Is AT&T ceding the Internet to Google? Are they willing to make angry statements that may harm their chances of FCC approval for the acquisition of the Dish Network?
In America, Comedians Tell It Like It Is On Net Neutrality
The debate on net neutrality for broadband in America creates lots of words, emotions and unfortunately, little comprehensible debate. That's because most of the debate is framed by lobbyists for the big companies that dominate the ISP business. But in America, the people who have the attention of the public are some of our best comedians, and recently two of them sounded off on net neutrality.
First was John Oliver, a British comedian and veteran of the internationally famous "fake news" show The Daily Show with Jon Stewart. On his new comedy news show on HBO, Last Week Tonight, last June he devoted most of the show to explaining net neutrality (watch it on YouTube here) and told everyone how to send a comment to the FCC which was then asking for public feedback. Up to that point, only a few tens of thousands of comments had been received. After the Oliver show, the comments poured in so fast it crashed the FCC servers. All told over >3,000,000 comments were filed!
Another regular on The Daily Show, John Hodgman, has been talking about Internet issues and net neutrality for years. As far back as 2006, Hodgman was using postal envelopes to explain how Internet service providers might let content from Google and Amazon through to consumers very easily while discriminating against content from other companies. In an essay on Tumblr, Hodgman took aim at large telecom companies who can "control what is increasingly a mandatory purchase" for many Americans: access to high-speed broadband that connects them to information, entertainment and economic opportunity.
"I believe in capitalism but not monopolies," Hodgman wrote. "I believe in entrepreneurship and I am not against government efforts to foster it. I believe more communities should invest in their own broadband to break regional telecom monopolies*. Personally I believe that the federal government should be laying down broadband like Eisenhower laid down interstates. And I believe preferential fast-laning for big companies will decrease competition and quality and ultimately hamper what is poised to be the most important area of economic, cultural, and technological innovation of our time."
*At the current time, 19 states in the US have laws prohibiting community broadband - laws written by lobbyists for current providers - and Tom Wheeler of the FCC has vowed to invalidate those laws. (editor)
How Fast Can A PON Go? At Least 100G.
Alcatel-Lucent says it will offer 40G with its 7360 Intelligent Services Access Manager FX platform that will support time- and wavelength-division multiplexed PON (TWDM-PON). The upgrade will support four wavelengths of 10 Gbps each and should be available in the first quarter of 2015. Read More.
Huawei announced that their optical access innovation lab has made a breakthrough in 100G-Passive Optical Network (100G-PON) optical access. This new 100G-PON technology uses a hybrid time-division and wavelength-division architecture to support a 4 x 25 Gbit/s downstream rate and a 4 x 10 Gbit/s upstream rate and enables 100 Gbit/s access rate per port on existing optical distribution networks (ODNs). The technology also establishes compatibility between 100G PON and GPON/10GPON/40G TWDM PON, allowing carriers to execute seamless upgrades to future-proof access networks.
Read more.
Tellabs OLANs Chosen For 13 College Campuses
Elauwit, a campus housing service provider, has expanded the deployment of Tellabs’ Optical LAN to five additional college campuses, following the deployment across eight colleges in 2013. Elauwit selected Tellabs’ Optical LAN due its scalability to easily meet students’ growing bandwidth needs now and for decades to come.
College students’ bandwidth demands are a major challenge for any student housing network. According to the 2014 State of ResNet report by ACUTA, increasing bandwidth is a popular approach to bandwidth management that schools are using to cope with this demand. Tellabs’ fiber-based Optical LAN will provide the campuses with virtually unlimited bandwidth, capable of speeds of up to 101 Tbps, to support RF video and ultra-high-speed wired and wireless Internet services.
Read more.
Tellabs passive OLAN (PON) was also selected by SK Food Group, for its new manufacturing facility in Columbus, Ohio. (Read more)
Safety On The Job
Safety is the most important part of any job. Installers need to understand the safety issues to be safe. An excellent guide to analyzing job hazards is from OSHA, the US Occupational Safety and Health Administration. Here is a link to their guide for job hazard analysis.
Worth Reading: Fiber testing practices are constantly evolving
Patrick McLaughlin, Chief Editor of Cabling Installation & Maintenance Magazine, has written an excellent article on the challenges of fiber optic testing. The way Patrick states the problem is astute: "The medium has proven itself to be stable and reliable; verifying or certifying that reliability can be a challenge.
"Many a teacher or trainer in the cabling industry has countless stories about the frequency with which fiber testing is carried out incorrectly. In many cases, characterizing the performance capabilities of installed fiber involves far more than connecting and pushing the "auto" button on a test instrument. "
Patrick goes on to investigate some of the typical problems encountered in fiber optic testing and provides to references (including FOA) that can help you understand the issues and test properly.
Read more in CI&M.
More articles in "Worth Reading" and on the FOA Pinterest Page "Worth Reading"
YOKOGAWA OTDR Has Extended range, High Resolution And Multitasking
One OTDR manufacturer you don't hear as much about is YOKOGAWA (formerly ANDO) which is too bad - they make some of the best OTDRs, exemplified by this new model AQ7280. Need long range - how about 50dB. High resolution - 0.6m dead zone. Like touch screens, but for some functions want hard buttons, it's got that. Options for VFL, microscope, light source and power meter, etc. - it has that too.
But the unique aspect of the YOKOGAWA AQ7280 is it offers multitasking - you can let do a trace with long averages while you inspect connectors, make power readings, use the VFL or other functions.
More info on the YOKOGAWA AQ7280.
FOA Certifies 50,000th Tech
The FOA passed a milestone in October, 2014 - our 50,000th certification!
Bradley Salmon, FOA's 50,000th certified tech, with Camosum College Instructors Trevor Curtis (L) and Gurbinder Dhade (R) in the Camosun lab.
Congratulations to Bradley, Trevor and Gurbinder - and thanks for your contributions to the FOA!
Clean Every Connector - A Lesson We Learned From Creating Lessons
In creating the fiber characterization curriculum, we got inputs from many experienced techs about the testing requirements. Everyone we talked to made a big point about cleaning and inspecting connectors before testing. Dirty connectors are a major problem with errors in testing. We've also seen that many installers think that if a connector, especially new connectors, has a "dust cap" on the connector, it does not need cleaning. WRONG!
The common name for the plastic caps on connector ferrules is "dust cap" and a friend says they are called "dust caps" because they are full of dust. Those plastic caps are made by the millions, popped out of plastic molding machines into barrels and stored until put into plastic bags. Whenever you remove one of them, clean the connector before testing or connecting it.
More on connector cleaning is here and here.
Good Practice Tools For OTDRs, All Free
FOA OTDR Simulator
You may already know that the FOA has a free OTDR Simulator you can download from our website (go here for directions) that allows you to practice using an OTDR on your PC, seeing the effects of changing setup parameters and analyzing dozens of real world traces. But here are two more tools that can be good for practice.
OTDR FAQs
Including more hints from FOA Master Instructor Terry O'Malley like tests on what the end of a fiber trace looks like with broken and cleaved fibers.
Frequently Asked Questions On OTDRS And Hints On Their Use
"Fiberizer" APP Reads, Analyzes OTDR Traces
Fiberizer is a iPhone/iPad APP that reads industry-standard ".sor" format files and allows trace analysis on your iPhone or iPad. An android version is in the works too. Read more about Fiberizer. And here are more directions on its use.
FOA Now Offers Fiber Optic Textbook and Web Pages In Spanish (French Online Guide available, textbook coming soon)
Guía de Referencia de la Asociación de Fibra Óptica (FOA) Sobre Fibra Óptica
Guía de estudio para la certificación de la FOA
Este libro es una guía de diseño e instalación para redes de cableado con fibra óptica. Fue escrito como un libro de referencia para los instructores y estudiantes en clases para certificación CFOT FOA, así como una referencia para cualquiera que trabaje en el campo. Este libro ofrece una cobertura amplia de los componentes y procesos de fibra óptica que se utilizan en todas las aplicaciones y prácticas de instalación.
Disponible desde CreateSpace, Amazon.com y muchos otros libreros
Available from CreateSpace, Amazon.com and many other booksellers
Qué es la FOA (What Is The FOA, in Spanish )
Plus, FOA Now Offers Its Basic Fiber Optic Online Guide Website In Spanish
La guía básica de fibra óptica de la FOA ha sido traducida al español. Es la versión completa de la FOA Guía básica Online traducido por especialistas técnicos, incluyendo todos los dibujos. Por favor, lea o comprar una copia del libro impreso y nos dan su opinión sobre cómo podemos mejorarlo!
Léela aquí.
Si usted está enseñando a la fibra óptica, póngase en contacto con nosotros ya que estamos ahora traduciendo el programa de formación FOA CFOT también.
If you are teaching fiber optics, contact us as we are now translating the FOA CFOT training curriculum also.
OLANs - Optical LANs
Free Fiber U Optical LAN (OLAN) Self-Study Program
FOA has added a new Fiber U self-study program on Optical LANs (OLANs). As you know, this is a hot topic in the IT world, so FOA has created an online course that allows you to study about OLANs (FOA includes fiber to the desk, fiber to the office and passive optical LANs) on your own time and schedule. You will be guided to material to read, videos to watch and even have quizzes to check your comprehension.
All Free!
OLANs on Fiber U
FOA OLAN Certification Released
OLANs are probably the most important new technology for enterprise networks since the introduction of structured cabling standards 22 years ago. For the last few months, FOA has been working with companies and groups interested in OLANs to create a certification for techs designing and installing them.
With OLANs, FOA has worked with leaders in the field to create technical materials on our FOA Guide website, Fiber U self-study program and YouTube channel already. We now have a curriculum ready our FOA-Approved schools which will make OLAN training available for those interested. Read More.
OLAN Resources
Over the last couple of years, we've written a lot about Optical LANs, either based on FTTH passive optical network (PON) or point-to-point (P2P) Ethernet architecture. The more we see of these types of networks, the more we appreciate their design and economy. But how about scale - how big can they get?
In November, we ran a picture story about the new San Diego Central Library which is using a Tellabs optical LAN using PON technology that was using about 1000 4 port drops. Now we hear another Tellabs customer has over 16,000 users. That must make it one of the biggest LANs in the world.
Here are more sources of information on optical LANs - BTW, they need a name - let's start calling them OLANs!
FOA Guide Page on OLANs and FOA YouTube Video
APOLAN, trade association for Optical LANs website http://www.apolanglobal.org/
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Events of Interest
Don't Miss These Seminars and Webinars:
Free Webcast: Best Practices for Deploying Preterminated Fiber-Optic Systems - Presented by FOA's Jim Hayes
Available anytime
Sign up here.
The popularity of preterminated fiber-optic systems continues to rise, as network owners realize the multidimensional benefits of these cablingsystems in several environments. Whether it is between servers inside a data center or between wireless towers outdoors, a preterminated fiber-optic cablingsystem offers efficiency in the fiber-connectivity process. These systems, however, do require careful forethought, planning, acceptance and, yes,installation. This webcast seminar, produced by Cabling Installation & Maintenance and delivered by Fiber Optic Association president Jim Hayes, describes the requirements and best practicesof deploying preterminated or “prefabricated” fiber-optic cabling. It covers the necessities of acceptance inspection, cleaning and testing, as well asproper design and installation techniques.
Sign up here.
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TIA FOTC offers regular webinars and archives them here so you can watch anytime.
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See the Light® Fiber Optic Training Program
Webinars, seminars and certification training classes.
Corning offers a library of more than 200 hundred videos that help our customers with everything from product preparation and installation to proper testing procedures. Our free Video Library Tool provides direct links to individual Corning videos, and allows you to filter by topic or area of interest. Register to download the Video Library Tool.
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 What's Happening @ FOA
FOA has three LinkedIn Groups
FOA - covers FOA, technology and jobs in the fiber optic marketplace
FOA Fiber Optic Training - open to all, covers fiber optic technology and training topics
FOA School Instructors - a closed group for instructors and administrators at FOA-approved schools
Grupo de La Asociación de Fibra Óptica FOA (Español)
 Corporate Memberships
FOA is now offering corporate memberships to companies involved in fiber optics as manufacturers, contractors, installers, etc. Corporate Membership gives companies discounts on memberships and direct certifications and access to special FOA materials for educating customers and employees. Read more.
FOA Standards:
FOA now offers free standards for datalinks and testing the installed fiber optic cable plant, patchcords and cable, optical power from transmitters or at receivers and OTDR testing.
What Is A Fiber Optic Cable Plant?
In a recent standards meeting, that issue was discussed with some disagreement as to what constituted a "cable plant." It seemed to be a perfect topic for another FOA "1Page Standard," so a draft version is now uploaded for review (FOA Standard FOA-6, Fiber Optic Cable Plant). Feel free to review it and comment to the FOA at info@thefoa.org.
Available also is a new standard for Datalinks.
Look for the "1 PageStandard" web page and in the FOA Online Reference Guide.
Go to the FOA "1 Page Standards"
Free For FOA Members: NECA/FOA 301 Fiber Optic Installation Standard
Standards cover components and systems and how to test them, but rarely get into installation issues. The FOA NECA 301 standard which covers installation of optical fiber systems has been revised for the second time, adding considerable new materials. This standard is derived from FOA educational material put in standards form and approved by ANSI as an American National Standard. It's specifically written to be used in contracts to define "installation in a neat and workmanlike manner." The standard is available from NECA. FOA members can go here for instructions on how to download your free copy.
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Free Fiber U Self-Study Programs
FOA's "Fiber U" free online self-study programs help you learn about fiber optics, study for FOA certifications or use them to help create "blended learning" classes. There are two new free online self-study programs on Fiber U. Fiber Optic Network Design is for those interested in learning more about how to design fiber optic networks or studying for the CFOS/D certification. FTTx is for those wanting to know more about fiber to the "x" - curb, home, wireless, etc. - or studying for the CFOS/H certification.
Got to Fiber U for more information.
FIber U Online Self-Study Program Offers Option Of Certificate of Completion
FOA has been offering quite a few free online self-study programs on Fiber U, our online learning site. We are always getting questions about getting a certificate for completing the course online, so we have setup an option to take a test online and get a certificate of completion for an online course.
We have just added a basic fiber optic course that anyone can take online, and when finished, there is an option to take an online exam that will provide a "Fiber U Certificate of Completion" when the exam is completed successfully. The course is still free but there is a small fee to cover costs to take the exam and get the certificate of completion.
While it's not FOA certification, FOA will recognize a Fiber U Certificate of Completion as background experience to qualify for applying for FOA certifications. We also intend to expand the program to more specialized topics as preparation for FOA specialist certifications.
If you have associates that want to get started in fiber, have them take this course online to get started. Go to Fiber U, click on the Fiber U Basics of Fiber Optics - Online Certificate Course and get started.
Lennie & Uncle Ted Now Available As Free Books on iTunes
 
Lennie Lightwave's Guide to Fiber Optics and Uncle Ted's Guide To Premises Cabling are now available free to iPad users who can download them from the Apple iTunes store.
Lennie's Guide has always been the world's favorite introduction to fiber optics. It was first published in the mid-1990s by Fotec, the fiber optic test equipment company famous for its "Fiber U" training conferences and more than 60,000 printed copies were distributed. Lennie was one of the earliest commercial webpages and is still online today (and as popular as ever) at http://lennielightwave.com. Uncle Ted's Guide was created at the request of Lennie readers who wanted a similar simple introduction to "Cat 5" wiring. This latest version of Uncle Ted's Guide covers the all premises cabling topics - wiring, fiber and wireless.
You can find these free guides on Apple's iTunes Store: Lennie Lightwave's Guide to Fiber Optics and Uncle Ted's Guide To Premises Cabling
FOA Now Offers Fiber Optic Textbook In Spanish (French coming soon)
Guía de Referencia de la Asociación de Fibra Óptica (FOA) Sobre Fibra Óptica
- Reference Books for FOA Certifications available on Kindle and iPad/iPhone as well as printed
  
We have created three new FOA books to be used in training for FOA certifications and as reference books for contractors, installers and end users of fiber optics. These books have full curriculum support, including free curriculum materials for teaching FOA certification courses. Because we are self-publishing these books using more modern "publish on demand" technology, they are easier to keep up to date, easier to buy and much, MUCH cheaper!
All are now available in print and electronically in Kindle and Apple iBook versions. The basic fiber optic book is also available as a self-study program in an Apple APP for iPad/iPhone/iPod.
Details on the new book each of the new books are at the book pages linked to the photos above.
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FOA iPad Apps
The FOA has just released its second APP for the iPad, a free "loss budget calculator," FOA LossCalc.
FOA LossCalc
 FOA LossCalc estimates the optical loss of a fiber optic link. This will save time for the installer of a fiber optic link needing to know whether test results are reasonable and/or make a "pass/fail" determination. It can also help the designer of a link to determine if communications equipment will operate over this link.
By choosing the type of link (singlemode or multimode) and specifying the length of the fiber and numbers of connections and splices, it will calculate the end to end loss of the link. The app has default specifications for singlemode and multimode links or the user may create custom setups with specifications appropriate for any application. http://itunes.apple.com/us/app/foa-losscalc/id476262894?mt=8&ls=1
Self -Study in Fiber Optics
 Our first app is a self-study version of the FOA Reference Guide to Fiber Optics. The FOA APP builds on the FOA basic fiber optic textbook to create an interactive learning environment that builds on the iBook electronic version of the book to add a guide to use for self-study and real-time testing that provides feedback on what you have learned and correct answers to questions answered incorrectly.
The FOA APP is priced at only $9.99, same as the iBook, so the self-study program is free. Download it from the Apple APP Store with your iPad or iTunes.
http://itunes.apple.com/us/app/foa-guide/id434354283?mt=8&ign-mpt=uo%3D4
FOA "Quickstart Guides"
In our continuing quest to help people understand how to test fiber optic cable plants and communications systems, we've created two more "QuickStart Guides to Fiber Optic Testing." They are simple, step-by-step guides on how to test fiber optic cable plants, patchcords or single cables using insertion loss or OTDR techniques and optical power from transceivers. It's as straightforward as it can get - what equipment do you need, what are the procedures for testing, options in implementing the test, measurement errors and documenting the results.
It can't get much simpler.
Send anybody you know who needs to know about fiber optic testing here to learn how it's done in a few minutes.
Testing Fiber Optic Cable Plants And Patchcords
Testing Fiber Optic Cable Plants With An OTDR
Measuring Optical Power In Communications Systems
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The FOA has many videos on , including two Lecture Series (Fiber Optics and Premises Cabling), Hands-On lectures on both and some other informational and instructional videos. For all the videos, go to the FOA Channel "thefoainc" or use the direct links below.
Two New Applications Videos
To accompany new FOA certifications in FTTA and Data Centers
FOA Lecture 37: FTTA (Fiber To The Antenna) and Data Center Cabling
FOA Lecture 38: Data Center Cabling
FOA Product Demonstrations
In the June FOA Newsletter, we talked about the new #M "disposable" cleaver, the Easy Cleaver, which is provided free with 3M connectors and mechanical splices that need cleavers. We got samples of the Easy Cleaver from 3M and tested them ourselves, and they work great. You can see for yourself how they work in this FOA YouTube Video about the Easy Cleaver.
We also tested the new Ripley/Miller FO-CF Center Feed Fiber Stripper and used it as an opportunity to show the other three common types of strippers, the Miller, MicroStrip and NoNik and how they are used. So you get a review of how to strip fiber and a product review of the new stripper in this FOA YouTube video about fiber strippers.
New FOA Lectures And Hands-On Videos
How to Talk Fiber Optics - an introduction to fiber optic jargon - the perfect place to start learning about fiber optics.
Where Are The Jobs In Fiber Optics? FOA talks about all the applications for fiber optics, what jobs involve and the qualifications for the workers in the field.
What's A "Network"
That's a common question from fiber and cabling people. Even though they may be installing the cable plants for networks, often the nature of networks is not something they have been exposed to, other than perhaps the catch-all "star network" description. But what is a network? What does it connect? How does it connect users and how does it allocate the bandwidth to them? How do various network types vary?
We've been working on some new YouTube videos on networks, starting as we usually do on a new subject with the basics. We have these three videos online now, but watch for more.
Fiber Optics - Live! A series of videos that use lab demonstrations to show how optical fiber works.
Prepolished/Splice Connector Termination (Panduit OptiCam)
Cabling Project Management - what's involved in a copper/fiber/wireless project -advice for the customer and the contractor
Hazards Of Counterfeit Cable
You may have read the stories we have written about the counterfeit "Cat 5" cable made from copper-clad aluminum rather than pure copper. Recently we tried an unscientific burn test on the cable compared to a known good UL tested cable and posted a video on YouTube. You can see the results below.
Counterfeit Cable Real UL-rated cable
The difference is obvious and the danger is real. Watch the video on YouTube: Premises Cabling Lecture 11: Counterfeit Cat 5 Cabling
View a complete list of FOA Videos with links to each video on YouTube.
View all the FOA Channel on YouTube.
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What's New in the FOA Online Fiber Optic Reference Guide?
We have been updating the Online Reference Guide to keep up with changes in the industry and adding lots of new pages of technical information.
New FOA Guide page on Metrology- the accuracy of measurements
Le Guide de référence pour la fibre optique de la FOA est maintenant disponible en français.
Updates for new FOA certifications in FTTA and Data Centers
What do you do when you need to test fiber or cable on a reel? Here is a new page on Bare Fiber Testing
Couplers or splitters are used in FTTH and OLANs. How do you Test Splitters?
Tapping fiber has been a big topic in the news. How do you tap fiber?
The page on Optical LANs (OLANs) has been expanded with new material and links.
What's A Network? A simple explanation of network types and operation has been added to the FOA Online Guide.
We have updated the "Datalinks" page.
Three new "Quickstart Guides" for fiber optic testing: cable plant & patchcord loss, power and OTDR
Learn More About OTDRs - Download a Free OTDR Simulator
More and more installers are being asked for OTDR testing but using these instruments is not easy. They are hard to set up properly and complicated to interpret the traces. Using the autotest function can lead to disastrous results! The FOA has a good tutorial on OTDRs on our Online Reference Guide and we added a free download of an OTDR simulator to the OTDR section so you can learn how to use an OTDR on your PC.
More New Info:
Links to manufacturers and distributors of fiber optic lighting products.
The FOA Online Fiber Optic Reference Guide has become very popular - perhaps the most popular technical website ever, typically with over 360,000 users downloading about 1.75 million pages in 2011! We continue updating materials regularly, keeping it as up to date as possible.
Find What You Want Using "Google Custom Search
 There's so much information on the FOA Tech Topics and Online Fiber Optic Reference Guide that even a well-organized Table of Contents isn't enough and when the material is always changing, an index is impossible to maintain. So the FOA is using the latest technology in search, Google Custom Search, which will allow you to search just the FOA Tech Topics and Online Fiber Optic Reference Guide for any topic you want to find more about. Try it!
Go to The FOA Online Fiber Optic Reference Guide.
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New Schools
The FOA welcomes the newest additions to our listing of FOA-Approved Training Organizations:
Jeff Moser, Instructor and Charles Headington, Training Director
San Luis Obispo Electrical Workers JATC
San Luis Obispo, CA 93401
CFOT, FOA Approved School #648
Find a listing of all the FOA-Approved schools here.
Find A FOA-Approved Training Organization
Most inqiries we get regarding finding a FOA-Approved training organization want to know two things: what school is closest to me or what school offers the certifications I need. The FOA has about 200 training organizations we have approved worldwide so finding the right one can be difficult! We've been looking at ways to make it easier, and we think we've got a good solution. In fact we have two solutions.
First we have added a sortable table of all the FOA-Approved schools.
You can also use our FOA Google Map to find FOA-Approved schools.
What Should A Fiber Optics or Cabling Tech Know and What Skills Do They Need?
FOA certifications are based on our KSAs - the Knowledge, Skills and Abilities that techs need to succeed. Read the FOA KSAs for fiber and cabling techs.
School News
Feedback
We always enjoy feedback, especially when it shows how great some FOA instructors are. These came from students of Tom Rauch, an instructor at BDI Datalynk:
"I took your fiber optics certification courses this past March. I just wanted to let you know that in two weeks I start working as a fiber optic technician with ___ up in ___. You mentioned on the first day of the course that there is always one guy in class who had rubbed his last two nickels together to be there and, in that instance, I was that guy. Now I'm going to be able to provide for my family like never before and I owe it to the certification that I received from you and BDI Datalynk. I just wanted to thank you again."
"Thanks to our tremendously knowledgeable and patient instructor Thomas Rauch, who was not only generous in sharing his wealth of information, but he did so with ease, humor and in a way that invited curiosity and participation. He was encouraging and proud of our accomplishments and helped us learn from our mistakes in a way that did not break our confidence, rather it pushed us to better results the next go around. The hands on labs were just AWESOME!" Just thought you should know what a class act you have representing you in his travels..... but then again you probably already knew that! : )
In almost 19 years at Verizon and having held numerous positions, I have gone through many training sessions. I cannot remember ever having been actually looking forward to coming back to class quickly after lunch, to get back to the hands on activities, and walking away with the sense of empowerment that the information presented was not only relevant but dead on point accurate! I will be signing up for the Outside Plant class on March! I can't say enough good things about Tom and his impact! Feel free to quote me, I can only imagine that he will open so many doors and change so many lives in the years to come, with his style of teaching! Great experience, awesome job!"
IBEW and FOA Partner on Fiber Optic Training
The International Brotherhood of Electrical Workers (IBEW) and the National Electrical Contractors Association(NECA) through the National Joint Apprenticeship and Training Committee (NJATC) in a partnership with the FOA has published a new textbook for training IBEW apprentices and journeymen in fiber optics. The new textbook uses the material from the FOA Reference Guide To Fiber Optics with new material and photos from other NJATC training partners.
FOA is pleased to have been able to assist the NJATC in the development of this new text. FOA has been a NJATC training partner for many years, including offering instructor training at more than 16 of the NJATC's summer National Training Institutes. A majority of IBEW NECA contractors do fiber optics and low voltage, especially for applications that combine electrical and communications cabling like smart grid, alternative energy, traffic controls, data centers, etc.
Quote from one of our certified instructors: I want to thank you and your organization for all the resources you provide for the students and the opportunity to offer the certification to the students. The fact that you published the book yourself to get the cost down and the unlimited free resources on your website shows a commitment to the public that is second to none. I let it be known to the students that the FOA is the best in the industry at supplying knowledge and resources related to the communication industry. I look forward to passing on the information that you provide for the industry.
Great Video About An FOA School And Their Training
BDI Datalynk trains at the Unversity of Central Florida. UCF created this incredible video on the BDI Datalynk program. It shows the power of what they offer on campuses around the US.
Watch the video here: http://www.ce.ucf.edu/Program/2583/Fiber-Optics-Network-Certification-Courses-Non-credit/
For more information, contact Bob Ballard, CFOS/I, BDI DataLynk, LLC, A Vietnam Veteran-Owned Company
www.bdidatalynk.com, Ph: 512-785-9024
RETURN TO INDEX
Good Question! Tech Questions/Comments Worth Repeating
Real Questions From FOA Newsletter Readers
OTDR Loopbacks
Q: We are looking at running a OTDR test across a pair of fibre’s but instead of running a OTDR test from A-B and then B-A, we are looping the fibres at exchange B and doing the OTDR test at on F1 &2 at Site A. We have launch cords and trail leads on Fibres one and two but I’m wondering what length of fibre should the loop be, would 50m be acceptable. Typically the sites are 10-20km apart.
A: Loopback tests are a good way to simplify OTDR testing. On a 10-20km run, the loopback needs to be long enough to allow both connections on the far end to be seen, so it depends on the pulse width of the OTDR. I suspect 50m is too short - I’d say use 500-1000m to ensure all the data is valid.
OTDRs On Live Networks
Q: I want ask you about OTDR measurment on live network. Is it mandatory to disconnect the far end patch cord before taking OTDR measurment . On our back bone network will an OTDR power is afect or damage line cards?
A: It depends on the network equipment - we would not recommend testing with equipment connected as OTDR pulses are very high power and will overload receivers. Do not take a chance!
Manufacturing Guide?
Q: Is there a guide published by FOA that provides insight as to the process of fiber optic manufacturing? It's my understanding that the guide stresses quality and controls to ensure performance and reduce product loss?
A: We do have a guide for manufacturers. It is mostly aimed at communications systems and components manufacture. Here is a link to download it.
How Long Does Termination Take?
FOA received a request from a consultant recently wondering if we had information on the termination times for fiber optic cables. After some looking in our archives, we realized we had a document online that compared times for various fiber optic termination processes. The paper was written after several FOA instructors did a comprehensive time and motion study on termination processes. The document is about 15 years old but still relevant.
You can read it here in the FOA Online Guide.
Q: I would like to ask a question about GPON security...is it possible to eavesdropping of the shared broadcast traffic from the OLT
A: GPON signals downstream are encrypted to prevent eavesdropping.
Connectors
Q: I have a 62.5 micron fiber and 50 micron connectors. We only need 62.5 capability. I have the tools to put the connector on the cable but will this cable work?
A: There are several ways to interpret your question.
1) If you are talking about adhesive/polish connectors, the hole in the connector is the same for 50/125 and 62.5/125 micron fibers, so the connector itself is the same.
2) If you are talking about prepolished/splice connectors where you cleave a fiber and insert it into the connector without polishing, you must have connectors with the proper size fiber or you can incur 2-4dB loss going from 62.5 to 50 micron fiber. See this page in the FOA Guide: http://thefoa.org/tech/fib62-50.htm
More info on termination can be found on the FOA Guide:
Fiber optic connectors: http://thefoa.org/tech/ref/OSP/term.html
And you can search the FOA Guide with our Google Custom Search: http://thefoa.org/tech/ref/contents.html#Test
Testing Connectors (From A Patchcord Maker)
Q: What are the chief defining standard(s) that specifies connector and assembly IL (insertion loss) and RL (return loss or reflectance) for both SM and MM fiber?
A: The description on our Guide is here: http://www.thefoa.org/tech/ref/testing/test/conntest.html
FOTP-34 covers connector testing as a qualification test for the type of connector - basically a "destructive" test for connector manufacturers.
Reflectance is described on that page and here also: http://www.thefoa.org/tech/ref/testing/test/reflectance.html
Testing an assembly like a patchcord is covered under FOTP-107 http://www.thefoa.org/tech/ref/testing/test/FOTP-171.html
What Is The "Index Profile" Of An Optical Fiber?
Q: In your textbook, you make mention of “Index Profile”(see pg 49). There are some other bits of information relating to that term. For multimode step-index, the profile appears square, for graded, rounded, and singlemode rectangular. I presume this is not the finish on the connector, but some other characteristic. I would appreciate if you could explain it to me.
A: The index profile of a fiber refers to a characteristic of the glass used to make the fiber, specifically the different materials in the core and cladding. "Index" means index of refraction, a characteristic of glass defined by the speed of light in the glass, technically abbreviated as "n" but often called "IR" in fiber optics. For most glass, the index of refraction is about 1.5 and the speed of light is calculated using v (the speed of light in the material) and c (the speed of light in a vacuum) as
V=C/n or for most glass, v = 300,000km per sec/1.5 = 200,000 km/s
That's right, light travels in glass at about 2/3 the speed of light in a vacuum, interestingly enough about the same speed as electrons in UTP copper cable and much slower than electrons in coax which is ~0.9c.
The choice of the index profile for fiber depends on the type of fiber and the transmission specifications desired.
Step index fiber has the core made completely of one type of glass and the cladding of another type with a slightly lower index of refraction to "trap" light in the core using what we call "total internal reflection."
Singlemode fiber is a special step index fiber with the core so small that light cannot bounce around - the core is only ~6 times the wavelength of the light and it is only transmitted in one mode, allowing much higher bandwidth and lower loss.
Graded index MM fiber is more complex. Graded index (GI) fiber has a range of materials in the core which are chosen to minimize modal dispersion caused by different path lengths of different modes being transmitted down the fiber. The core index profile is curved - a parabola to be exact - with lower index glass on the outside of the core. The lower index glass transmits the higher angle light rays (called high order modes) faster than the lower index glass near the center of the core. The index profile of the core of multimode GI fiber is not continuous, which is hard if not impossible to manufacture, but is in steps, from hundreds of steps to thousands depending on the fiber. As a mode of light goes through each step, it is bent slightly until it is reflected back toward the core of the fiber. Since the light is going into lower index material in the outside of the core, it speeds up compared to the speed at the center of the core. By carefully designing and manufacturing the fiber, you can get the average speed of a higher-order mode approximately the same as the modes going straight down the fiber, reducing modal dispersion.
A more complete explanation is on the page in the FOA online reference guide about fiber here: http://www.thefoa.org/tech/ref/basic/fiber.html
Tests For Fiber Optic Cable Plants
Q: I did some research and I noticed that there is a bunch of tests that can be done to fiber optics and I was wondering if there is a list of primary tests that can be done as a basic test.
A: Fiber optic testing does have a hierarchy of tests.
- At the top of the list is "insertion loss" testing which uses a light source and power meter to test the fibers in the same way that a communications system transmits over the fiber. It is a simple test and the equipment needed is inexpensive.
- Techs will also use a microscope to inspect the fiber optic connectors for dirt and damage, a big issue for fiber.
- The instrument called an "OTDR" takes a snapshot of the fiber using a technique like radar. Most outside plant cables are tested with an OTDR and the data ( the snapshots are called "traces") stored for future reference. OTDRs are more expensive and require more training to use properly.
Here is a link to a page on the FOA Guide site that explains the technical,details: http://thefoa.org/tech/ref/testing/test/OFSTP-14.html
FOA also has information just for users of fiber optic networks, see http://thefoa.org/tech/guides/UG3.pdf
Singlemode or Multimode Connectors
Q: Can I use the same connectors for epoxy or anareobic terminations?
A: Connectors for singlemode and multimode fiber are different. SM connectors have tighter tolerances than multimode with slightly smaller hole in ferrule. Thus SM fiber should not be used with MM connectors because the tolerances will lead to core offset and higher loss. Likewise MM fiber might not fit in SM connector hole.
Cascading PON Splitters
Q: How does on design a PON or POL network with cascaded splitters?
A: The splitters can be placed where it makes sense or to save fiber, but the total split ratio of cascaded splitters should not exceed the maximum split ratio for the system standard, e.g. 64 for GPON (see the table here http://www.thefoa.org/tech/ref/appln/FTTH-PON.html).
The split ratios multiply, so if the maximum split is 64X, you can have:
64X only
32X and 2X = 64X (of course this is the same as 2X and 32X, if you are thinking the first splitter is nearer the OLT.)
16X and 4X = 64X
8X and 8X = 64X
Also, each system has a "Power Budget" (see http://www.thefoa.org/tech/lossbudg.htm) that is the minimum and maximum loss the system can tolerate over the cable plant. For the most popular versions of GPON, the power budget is 13dB minimum and 28dB maximum (so the cable plant, including splitters, between the OLT and ONT must have at least 13dB but no more than 28dB.) Within any given subsystem using one OLT port, you can have a different loss to each ONT (and you probably will) but the system will work as long as the loss in the link is between 13 and 28dB.
In addition, each system has a maximum number of ONTs that can be supported by the software, 64 in the GPON standard.
Encircled Flux Continues to Be A Problem (Update - see HOML article above)
Question from a installer: What’s the latest on encircled flux? We purchased some Flux encircled flux controllers at over $400 each. The warranty on those is only 90 days so they’re very expensive to replace, especially compared with the cost of new fiber jumpers. Do you know of a company that makes these besides ____? They don’t even service them and I have doubts about the quality. We’ve had problems with 2 that we never have had with fiber jumpers that we test with.
Answer: It's a long story, but....TIA is changing OFSTP-14 to only require EF on 50/125 Laser Optimized fibers at 850nm because it's unnecessary on other fibers and not proven worthwhile. Internationally, it's still called for everywhere, as far as I know. The only makers of those devices as far as we know is Arden Photonics in the UK. http://www.ardenphotonics.com/ The entire EF issue is based around products they alone make as far as we know. TIA knows the devices have a limited lifetime- the TR-42.11 committee has discussed the subject. The ISO/IEC committee behind it has said the old TIA mandrel wrap meets the EF standard. We quote the reference in our Guide page on EF.
FOA Loss Budget App
Q: How do you calculate the Avg loss?
A: The app is programmed to allow multiple setups of component loss values to ensure the values are appropriate to the application. There are default values for SM and MM using typical values (based on FOA experience) and max values (TIA or ISO/IEC standards which are worst case values decided ny manufacturers.)
When you create your own setup, you can set the typical (Splice Loss Typ) and maximum (just says Splice Loss for example) as you desire, so the app gives a range of loss values that will be what you expect (average or typical) and (Max) to compare against the Power Budget of the communication system when designing the cable plant and comparing against test results after installation. The "Help" section gives the values used in the default setups.
Polishing Pucks
Q: Why are there so many types of polishing pucks? Which ones are best?
A: Polishing pucks are available in more varieties than M&Ms - plastic, glass-fllled plastic, stainless steel, steel with carbide inserts, etc. We have used most types and find the inexpensive glass-filled plastic ones work fine. You need one for 2.5mm ferrule connectors (ST/SC/FC) and one for 1.25mm ferrule connectors (LC).
There are some caveats in using them that makes more difference than you think.
1. Polish on a flat plate topped with 1/8" (3mm) rubber of ~80 durometer on which the polishing film is placed.
2. Put the connector in the puck, place one side on the polishing film and gently lower it to the surface of the film to not damage the protruding fiber.
3. Calibrate your polishing pressure - it requires less than most people think. Watch this video from a couple of our instructors who used a postal scale to teach how much pressure to use: http://www.youtube.com/watch?v=vWEGBruEfG4
4. Clean the puck and polishing film after each use with a lint-free wipe and 99% isopropyl alcohol to remove the grit that accumulates - use the same cleaning wipes you use to clean the connector and dry it off, then clean the film and puck, then discard it.
Relative vs. Absolute Power Measurements
Q: I am thinking how to minimize uncertainty when doing relative measurements. I am mostly interested not in absolute power but rather a relative one, that is measuring loss not absolute power. Will any source of error be smaller or maybe vanish as a result of ratio? What can I do to reduce the uncertainty of the ratio of powers?
A: When measuring relative power, e.g. when measuring loss, the issue is relative power and depends on the linearity of the meter. The linearity of the meter can be affected by two issues - the slope of the calibration curve and the offset where the meter autoranges. Most meters read power over a large dynamic range, 1,000,000 to 1 (60dB) is not uncommon, and that is beyond the range of the electronics in the meter. To get this kind of range, the meters have a range switch controlled by the microprocessor that changes the gain in the amplifier attached to the detector. The amplifiers are linear and dB is calculated by the microprocessor so it does not matter if you measure in dB or W and calculate dB yourself. Calibration of the meter should include looking at the autoranging points to ensure minimal nonlinearity. Look at this graph:
When the meter measures two power levels away from the autorange point, the error is simply the error in the calibration slope, which will be proportional to the range measured. For reading of a few dB, the error is usually very small, ~0.0x dB. If the measurement includes the autorange point, the error can be higher, depending on the amount of error in the autoranging.
This argues for having your meters calibrated by a factory-approved facility who knows where the autorange points are and can carefully calibrate around them. If you just check calibration at low and high points, you may miss autorange problems.
How to Clean POF (plastic optical fiber)
Q: I heard that plastic fibres such as PMMA can suffer damage from cleaning from an alcohol solution. Are there alternate cleaning solutions available for these types of fibres."
A: You can use a 10/90 mix of isopropyl alcohol/water. Typically use with a lint free swab. (from out POF consultants)
Using Older Fiber For Faster Systems
Question: My client has SMF 28 and Metrocor fiber cables that were manufactured c.2000. Please let me know whether these cables are obsolete or if they can be used for today's applications.
Answer: There is no definitive answer to your questions. The fiber may be used for upgraded systems but it must be tested for CD and PMD and results compared to the requirements of the systems being considered.
Testing Bare Fibers With OTDR
Q: We are starting to test some OPGW cables. We have an OTDR but we don’t find some reusable connectors. If we have to test an OPGW with 48 fibres, we can’t set up 48 SC connectors!
Are there some reusable connectors in the commerce?
A: I assume you mean you need to test with a bare fiber on the OPGW. For testing bare fiber, use a splice, not a connector. Have a long pigtail on the OTDR as a launch cable, long enough for the test pulse to settle, say 100-500m, then use a splice for a temporary connection. You can fusion splice the fibers then cut the splice out or use a removable splice like the Corning Camsplice (http://catalog.corning.com/opcomm/en-US/catalog/ProductDetails.aspx?cid=&pid=17929&vid=18219)
If you use a mechanical splice, you need a high quality cleaver just like with fusion splicing and after several uses, you need to add more index matching gel or liquid - mineral oil works OK. See the FOA page on Testing Bare Fiber.
Getting Started
Q: I have been asked internally what I would do and how I would start a data division. I know from looking at your website that you understand it and I was hoping you could give me some bullet points on how I would get a Tele/Data division started up from its infant stages. Any advice you could give me would be appreciated.
A: Basically, the cabling installation is similar to electrical, just the termination and splicing are different and testing is specialized. All these are easily learned. FOA has Fiber U free online training in both fiber and structured cabling (fiberu.org) and 80 YouTube Videos on this subject (FOA channel "thefoainc" you can use to become more familiar with the topics. Through the FOA we have approved schools that offer training and certification, courses you can take at scheduled locations or have brought to your facility.
OTDR Calibration
Q: I read on your website information about ODTR, and I'm curios if you could offer some more information. I am interested in all compatible standards considering OTDR Calibration. So far I managed to find out that there is IEC 61746-1 standard for Calibration, and also TIA/EIA-455-226 wich is adoption of IEC 61746-1. And I concluded that those 2 are surely internationally approved and do the same thing. I found in some website the offer for calibration performing both NIST traceable, and TIA 455.
I could not find out what is relation between TIA and NIST traceable calibration standards ( if there are any), is it the same or those 2 are compatible (if u use one of those for OTDR calibration it is enough)or those 2 are different and you need to perform both.
A: NIST was approached for OTDR calibration in the 1980s and considered making a transfer standard for use in calibrating OTDRs. It was intended to be a sample fiber of known index of refraction and length with splices and connectors of known loss. However the project was never completed as it could not be made agreeable to all parties. Many thought a calibration based on a device that would simulate the return from a cable was more accurate. Both these methods have been used since, but NIST never produced an OTDR calibration system like they did for optical power meters (I worked on that one myself.)
Other than the IEC document, I know of no other standards or traceable calibration by a national standards lab.
Is A Flashlight Test Adequate?
Q: I contracted a firm to install an OM3 of 200 meters. On one end I have an SFP 1000SX ,on the other a 1000SX converter from optical to UTP. We made pings but they never reached, and I didn’t see the laser at the extreme of the fiber. They promised me to send me the certification they supposely made ,though they assured me the fiber is ok, because WITH A FLASHLIGHT THEY SENT WHITE LIGHT FROM ONE SIDE TO THE OTHER AND IT WAS VISIBLE. I saw the light too, and I thought the culprit was my switch or my SFP. I want to know: is this a good demonstration that the fiber is ok?
A: A visual continuity test is not adequate - your eye is not calibrated! The power of the lamp is unimportant as each eye’s sensitivity is different. And your eye probably cannot see the light from a 850nm VCSEL source - most people’s eyes are not sensitive at that infrared wavelength. The installer should have tested the link with a light source and power meter (http://www.thefoa.org/tech/ref/testing/test/OFSTP-14.html) and given you the loss in dB. The connectors should also be inspected with a microscope to ensure proper polishing and cleanliness (http://www.thefoa.org/tech/ref/testing/test/scope.html). If the SFP output is -6dBm, what is the power at the receiver? 1000base-SX is supposed to work with 4.5dB loss (see http://www.thefoa.org/tech/Linkspec.htm). The fiber loss should be ~0.6 dB, so you must have >4dB connector losses! That says bad installation! The 1000SX link should work over 200m if the fiber has been properly installed.
Mismatched Fibers Working
Q: I have an existing light blue, 50 micron, armored fiber cable, with 3 pairs, between data closets. The first pair is used successfully with my 10 GB data network, using all 50 micron patch cables and connectors to Dell Force 10 switches.
My issue is with a secondary network. I would like to utilize a second pair on the 50 micron riser. But, the patch cables from each side will be 62.5 microns (orange) cables that go into my HP switches, with 1GB connectors. I know mixing 50 to 62.5 is NOT best practice according to your site (http://www.thefoa.org/tech/fib62-50.htm), but I have tested the connection from 1 HP switch to the other, utilizing the 62.5 micron patch cables, into the 50 micron uplink, with success.
Should this even be working? Is it strange that it works at all? If not, should I be even more concerned, if I connect 48 people using this same scenario?
A: This is a common problem. There is an explanation and two solutions.
Explanation: Every link has some margin for optical power - that is it has more power at the receiver than the minimum required. The link where you have Trans>62.5>50>62.5>receiver fiber will has a higher loss at the 62.5>50 connection near the transmitter and a lower loss (even than connections of two fibers the same size), since the larger fiber on the receiver end negates the losses due to most alignment factors - big to small means very low loss. Since the link works, the excess loss at the 62.5>50 connection near the transmitter is compensated by the lower loss of the 50>62.5 connection near the receiver and is within the original margin of the link. Thus it works.
Solution #1, document the mismatch and leave it alone - it works
Soution #2, replace the patchcords with 50/125 patchcords, since there may be a slightly lower coupled power from the transmitter, but not much since both are VCSELs* with similar power outputs, and the receiver will pick up all the light. In other words, using 50/125 patchcords will probably have higher margin.
* Since fiber networks moved to gigabit speeds, the old LEDs used at 100Mb/s were unable to cope, so everybody switched to an inexpensive laser a VCSEL - vertical cavity surface emitting laser - that launches power in a very narrow beam in the center of the fiber, smaller than a 50 micron core and way smaller than a 62.5 micron core. http://www.thefoa.org/tech/ref/appln/transceiver.html Thus there is no penalty to using the smaller fiber at the transmitter end.
We recommend you try #2.
Older Fiber?
Q: I have some 62.5 mm and sm inside fiber plant over 20 years old. When is a good time to upgrade?
A: When you need to or have to. If it's working OK, there is no need to upgrade!
"Connector Loss" or "Connection Loss"
Q: I have always counted the loss of a connector as .75 dB (568B-3) and 1.5 for a mated pair. Is that correct?
A: While the industry always says "connector" loss, it is actually "connection" loss. As we explain in the page on termination and splicing (http://www.thefoa.org/tech/ref/basic/term.html) When we say "connector" loss, we really mean "connection" loss - the loss of a mated pair of connectors, expressed in "dB." Thus, testing connectors requires mating them to reference connectors which must be high quality connectors themselves to not adversely affect the measured loss when mated to an unknown connector. This is an important point often not fully explained. In order to measure the loss of the connectors you must mate them to a similar, known good, connector. When a connector being tested is mated to several different connectors, it may have different losses, because those losses are dependent on the reference connector it is mated to."
The TIA spec of 0.75dB is for a mated pair of connectors. If you have been passing connectors tested @ 1.5dB loss....you may have some very bad connectors in your cabling!
Changing From OM2 to OM3/4 Fiber
Q: We have a system currently that is comprised of OM2 fibre with LED transceivers. There is a proposal to change the fibre to OM3 and I have been asked to look at how the change will affect the transceivers currently fitted which will remain the same until a later upgrade. From looking around on various forums I can see that OM3 is optimised for lasers, however the existing hardware will remain as LED. My understanding is that OM3 is simply fibre manufactured to a better standard than OM2 with significantly less internal defects. This leads me to think that switching from OM2 to OM3 fibre would not have any negative effect on the existing hardware and would probably reduce the overall link loss. I am also looking at whether we can use the same connectors, again looking on the internet I can see that the physical dimensions are the same, however are some connectors only certified to OM2?
A: The difference between OM2, OM3 and OM4 fiber is the "modal" bandwidth potential of the fiber at 850nm. OM2 and OM3 fiber is optimized for bandwidth with 850nm VCSELs and has no bandwidth advantage with 1300nm LEDs. The optimization is done by more careful manufacture of the graded index profile of the core of the fiber, nothing else. There is no reason to use OM3 or OM4 fiber with an LED transceiver as the LED cannot be modulated at high speed and the LED bandwidth in any of these fiber is limited by chromatic dispersion which is not significantly different in any of the higher grade fibers. The attenuation coefficient of these fibers is not enough different to justify replacement either. See http://www.thefoa.org/tech/ref/basic/fiber.html for more info on fiber. They all use the same connectors. Fiber optic connectors are not a factor in the bandwidth of the fiber.
Microscope Magnification (11/13)
Q: I am doing a lot of fiber optic jumpers for control systems, either single mode or multimode. I want to get a scope to inspect the ends after I clean them would you recommend a 200X, 400X handheld or one similar to a Noyes OFS 300 200C?
A: We prefer to use lower magnification and have a wider view so I can see more of the ferrule to determine its condition. You can see the fiber effectively at 100X but 200X may be better. 400X may be too much for most tasks like inspecting for cleanliness, but may be good if you are polishing SM for good reflectance. We've used the Westover units for years because they offer two different methods of illumination - direct and at an angle. If you are doing a lot of patchcords, I recommend a video microscope. I've used the Noyes unit that interfaces to a PC to create the FOA Microscope Inspection YouTube video here: http://www.youtube.com/watch?v=IyumH8CiUPQ&feature=youtu.be and it works well.
Recycling Cabling
Q: Who can I contact regarding recycling cable I am removing from a building?
A: Here are some people who say they recycle fiber optic cable or at least know how to do it:
http://www.scottrecycling.com/complete.html
http://www.scrapmonster.com/selloffer/fiber-optic-cable/10400
http://www.dnvkema.com/services/ces/hse/recycling/recycling-cables.aspx
http://tmscrapmetals.com/Recycling.html
Tech Hint: Did You Know You Have A Fiber Optic Tester In Your Pocket?
Yes! That old mobile phone has a camera which may be sensitive to infrared light - lots more than your eye - and can detect light in an optical fiber or from a transmitter. Chris Hillyer,CFOT/CFOS/I, Master Instructor, Northern California Sound & Communication JATC sent us some photos showing how this works. See below or the video now on YouTube. Update: You should check out your old cell phones before you recycle them. We've found older models use sensors which are better at infrared than the newer ones which take better pictures. This is a good use for your old cell phones hiding in the drawer!
Fiber Cleaning
This is a topic we keep reminding everybody about, and here is why:
From a contrator in the Middle East: Here some samples of the connectors for SM fiber already installed in the system we were testing.
 
As you can see, the dirt is large compared to the size of the fiber (dark gray), and the core (not visible here) is only 9/125 of the overall diameter of the fiber! More on cleaning. See Product News below for links to vendors of fiber cleaning products.
See news about Fiber Optic Cleaning Videos on YouTube by ITW Chemtronics below.
Fiber Optic Cleaning Videos on YouTube
See news about Fiber Optic Cleaning Videos on YouTube by ITW Chemtronics three fiber optic cleaning videos on YouTUbe covering Dry Cleaning, Wet-Dry Method, FiberWash and Combination Cleaning. They are good explanations of cleaning processes - the Wet-Dry is especially interesting.
- Westover Application Notes And Cleaning Video
- Westover has several application notes on inspecting and cleaning fiber optic connectors. The video is a big file (50+MB) but a good tutorial.
- Download page: http://www.westoverfiber.com/Support/downloads.php
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Measurement Uncertainty: Everyone testing fiber optics should understand that every measurement has some uncertainty - whether you are measuring loss, length, wavelength, power, etc. Knowing that uncertainty is very important to interpreting the measurement. It's worthwhile to read and understand the issue of measurement accuracy covered in this page of the FOA Online Fiber Optic Reference Guide.
RETURN TO INDEX
Worth Reading or Watching:
What Is The FOA?
Hear FOA President Jim Hayes tell the FOA Story in a 2-part interview by Sound & Video Contractor Contributing Editor Bennett Liles. It tells about the FOA history, goals and achievements.
Part 1: http://svconline.com/podcasts/audio/fiber_optic_association_part1/index.html.
Part 2 http://svconline.com/podcasts/audio/inside-fiber-optic-association2-0924/index.html.
Australia's Standard Is Comprehensive Guide To Customer Cabling (Get your copy free)
In answering a recent technical questino, Trevor Conquest in Australia pointed to the Australian Standard "Installation Requirements For Customer Cabling." When we checked, it is on the web and can be downloaded. It's a big book - 220 pages - full of details for fiber and copper installations. We recommend you download yourself a copy - go here.
Demystify fiber inspection probe technical specifications - From EXFO
The intent of this application note is to promote a better understanding of video inspection probe specifications and features. Properly understanding the key specifications and features will greatly facilitate the decision process involved in acquiring such devices. Understanding the key aspects of fiber inspection probes will also help users understand how fiber inspection probes operate, thus enabling them to maximize the full potential of these devices. Read more.
Where In The US Do Contractors Need Licenses For Fiber Optics?
We often get asked where in the US do contractors doing fiber optic installations need licenses. We found a good website for that information, the NECA -NEIS website. You might remember NECA-EIS, as they are the partner with the FOA in the NECA/FOA 301 Fiber Optic Installation Standard. NECA is the National Electrical Contractors Association and NEIS stands for National Electrical Installation Standards. They have a very easy to use map and table that gives you data on every state in the US, so mark these pages for future reference.
NECA/NEIS
http://www.neca-neis.org (See “State Regulations”)
http://www.neca-neis.org/state/index.cfm?fa=state_regs (all electrical licensing)
Low Voltage: http://www.neca-neis.org/state/index.cfm?fa=specialty_licensing
How Is Fiber Manufactured?
OFS invites you on a tour of their multimode fiber manufacturing facilities in this new 5-minute video. You will see their highly automated manufacturing operation in Sturbridge, Mass., including their patented MCVD preform fabrication process to fiber draw and final product testing. With a technological heritage dating back to AT&T and Bell Labs, OFS has been manufacturing high-quality multimode fiber since 1981.
Watch the video here.
Want To Know Where Submarine Fiber Optic Cables Run?
There is a good map online by TeleGeography you can access here.
Benchmarking Fusion Splicing And Selecting Singlemode Fiber
We've been asked many times "How long does it take to splice a cable?" It's not a simple answer as it varies with the number of fibers in the cable and the work setup, including whether one or two techs are working at a job site. FOA Master Instructor Joe Botha of Triple Play in South Africa did his own analysis based on decades of experience both splicing cables and teaching others how to do it properly. This is one of the best analyses we have seen because Joe includes prep times as well as splicing times and differentiates between one tech and two techs working together. He adds some other tips on fusion splicing too. This should be mandatory reading for every tech and given to every student! Here is Joe's splicing analysis.
Joe also has an excellent writeup on how to choose singlemode fiber that helps understanding the different types of G.6xx fiber. Read it here.
And you will want to read Joe's report on splicing different types of SM fiber, including bend-insensitive (G.657) fiber. Read it here.
Free - Mike Holt's Explanation Of The US National Electrical Code (NEC) For Communications Cables
Mike Holt is the acknowledged expert of the US National Electrical Code (NEC). His books and seminars are highly praised for their ability to make a very complicated standard (that is in fact Code - law - in most areas of the US) easily understood. Part of the appeal is Mike's great drawings that make understanding so much easier. Mike makes Chapter 8 of his book available free. It covers communications cables, telephones, LANs, CATV and CCTV, for premises applications. Even if you live in a region or country where the NEC is not the law, you may find this interesting.
Download Mike's Chapter Here.
Fiber Optic Cleaning Videos on YouTube
ITW Chemtronics has three fiber optic cleaning videos on covering Dry Cleaning, Wet-Dry Method, FiberWash and Combination Cleaning. They are good explanations of cleaning processes - the Wet-Dry is especially interesting.
- Westover Application Notes And Cleaning Video
- Westover has several application notes on inspecting and cleaning fiber optic connectors. The video is a big file (50+MB) but a good tutorial.
- Download page: http://www.westoverfiber.com/Support/downloads.php
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A Documentary Treasure on the History of the Internet
15 minutes of a rarely-seen BBC documentary demolish the myth that ARPAnet was inspired by nuclear war, and explain the far more intriguing truth.
http://www.technologyreview.com/blog/mimssbits/26719/?nlid=4433
Ensuring Distance Accuracy On OTDR Measurements
By JDSU.
JDSU Reference Guide to Fiber Optic Testing
Volume 1 focuses on Basic Fiber testing and Volume 2 is geared toward fiber optic installers, project managers, telecom technicians and engineers who need to understand fiber networks. Volume 2 also covers Chromatic Dispersion, Polarization Mode Dispersion, Attenuation Profile and Fiber Link and Network Characterization. A 3rd volume, a glossary of fiber optic terms, is also available for download.
This is a "MUST HAVE" for all fiber optic techs. Download your free copies here.
We used this book as one of our references in creating a new page in the FOA Online Reference Guide on chromatic dispersion (CD) and polarization-mode dispersion (PMD).
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- Download yourself a copy and read it!
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Good Technical Website For Installers
American Polywater (http://www.polywater.com/) has one of the best technical website for cable installers. Check out their website, especially “Videos,” “Engineer’s Corner” and “Calculators.” http://www.polywater.com/NNNBSL.pdf
Fiber Optic Safety Poster
We've had numerous requests to reprint our guidelines on safety when working with fiber optics, so we have created a "Safety Poster" for you to print and post in your classroom, worksite, etc. We suggest giving a copy to every student and installer.
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" Heard on the Street" is a monthly online newsletter from Frank Bisbee of Communications Planning Corporation that covers the telecommunications and cabling businesses. Each month includes news from manufacturers, trade associations and professional societies like the FOA. You can read the current issue and back issues online.
IGI, a major market research and technology reporting company (the "Active Optical Cables" below) is offering a a free one year subscription to one of our fiber optics newsletters to FOA members. All they have to do is to send IGI an e-mail stating which newsletter they would like to get. See http://www.igigroup.com/nl.html for a listing of IGI Newsletters.
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FOA Tech Topics -
A Fiber Optic Tester In Your Pocket? (See the video on )
Yes! The camera in your cell phone is sensitive to infrared light - lots more than your eye - and can detect light in an optical fiber or from a transmitter. Chris Hillyer,CFOT/CFOS/I, Master Instructor, Northern California Sound & Communication JATC brought this to our attention.
 
If you have an old cell phone, try it too. Our experience is that older cell phone cameras have better sensitivity at IR wavelengths than newer phones, so you may want to toss that old phone into the toolbox.
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Product News
YOKOGAWA OTDR Has Extended range, High Resolution And Multitasking
One OTDR manufacturer you don't hear as much about is YOKOGAWA (formerly ANDO) which is too bad - they make some of the best OTDRs, exemplified by this new model AQ7280. Need long range - how about 50dB. High resolution - 0.6m dead zone. Like touch screens, but for some functions want hard buttons, it's got that. Options for VFL, microscope, light source and power meter, etc. - it has that too.
But the unique aspect of the YOKOGAWA AQ7280 is it offers multitasking - you can let do a trace with long averages while you inspect connectors, make power readings, use the VFL or other functions.
More info on the YOKOGAWA AQ7280.
Need A Fiber Optic Cable That's Waterproof And Floats?
Linden Photonics can help you. The specialize in special underwater cables for towed vehicles or ROVs. Read more.
How To Make Space For More Cables In Full Conduits
Traditionally, underground fiber has been placed in plastic innerducts in conduit. About a decade ago, MaxCell "fabric" innerducts were introduced. They provided the protection needed during installation and greatly increased the availabe space in conduit. Recently, the company has introduced an interesting technique to remove plastic innerduct in place to make more space for cables in current ducts.
Here are photos from a MaxCell YouTube video showing what we are describing.
Before, with innerduct in place:
After, with the MaxCell innerduct and more cables:
We suggest you watch the overview: http://www.youtube.com/watch?v=sf726tPAvt8&list=PLDfVYzTi8g93zg1ZYWE-bINEeADVgEMsC&index=1
Then watch some actual examples of the innerduct removal process: http://www.youtube.com/watch?v=Rs0bfd79AYM&feature=youtu.be&list=PLDfVYzTi8g93zg1ZYWE-bINEeADVgEMsC
A Really Bright Visual Fault Locator
SKY Technologies recently sent us a VFL to evaluate. With a VFL, you need quite a bit of power to see splices and through some cable jackets, even MM orange (the cable in the photo) but especially other colors, so high power is an advantage. This VFL is the brightest we have seen - bright enough that you want to ensure it's aimed away from your eyes when you turn it on! It has CE and RoHS approval. Model FT650H-50B. Contact SKY for more information.
SKY Technologies Inc.
http://skytechlasers.com
http://visualfaultlocator.net
1.888.878.2374
Switch For Testing MTP/MPO Cables - Now Available for 12 or 24 fiber MPOs
Fibernext has introduced a portable switch for testing multifiber MTP/MPO connectors. You can also watch the YouTube video here.
Recycling Communications Cable
FOA was contacted by a company that recycles electronics communications equipment and cabling. CommuniCom recycles cable/metals/e-waste for Telcos and CATVs. They also recycle Fiber Optic Cable and associated Materials (the fiber scrap). And, they reclaim OSP abandoned copper cables (abandoned from road moves or FTTx growth). This is a huge part of our business. They do the work (permitting/locates/labor) for free and we revenue share back with our clients (telcos).
Contact Steve Maginnis
smaginnis@communicominc.com
www.communicominc.com
803.371.5436 (cell)
Micro-Trenching, Cable Removal
Nano-Trench offers products for micro (or I guess they call it nano-) trenching and their website is very informative. They also have Kabel-X, a method of extracting copper cables from old conduit. Both websites are informative and interesting. Watch this video on the cable removal process!
Protecting Pedestals From Rodents
Pedestals and underground vaults can be damaged by rodents who come up through the base and damage cables. Uraseal "Drain N'Seal" foam deters mice from taking up residence in your pedestals. They have some good videos on using their product.
Used Test Equipment – Buy or Sell
http://www.testequipmentconnection.com/
Have you read the FOA Tech Topics on Cleaning?
As much as 70% of the problems associated with deploying fiber result from something as simple as dirty connectors according to JDSU. Telephony Online.
US Conec's videos on cleaning fibers - show's the results of proper cleaning.
Westover
- AFL
ITW Chemtronics
Cleantex Alco Pads
MicroCare
Seiko-Giken
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FTTH Notes:
Many States In the US Restrict Municipal Networks
As reported in the website "Community Broadband Networks," many municipalities are creating their own networks, including FTTH like Chattanooga and Clarksville, TN, etc. But in 19 of the US states, there are laws that handicap municipalities or outright ban their offering "telecom" services. (See the list of laws compiled by Optica here.) Obviously, these laws were passed to protect the (usually monopoly) telecom and CATV providers who do not want competition. But they also make it difficult or impossible for many areas to get broadband.
Does anybody know if these laws prohibit a municipality from building a fiber network and then leasing it to an Internet service provider? Obviously, FTTH needs good lawyers too.
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FTTH in MDUs (Multiple Dwelling Units)
When we talk about FTTH, we often assume we are installing the fiber to a “home” where it terminates in a optical line terminal (OLT) and services (voice, data and video) are delivered inside the subscriber’s "home." But since we may have detached single-family homes, row houses or living units in a large building, the situations can be quite different, requiring different architectures and installation practices. To clarify the options for fiber in MDUs, FOA has created a new page in our FTTx section of the FOA Guide to explain the options.
FOA Guide: FTTH in MDUs
Testing FTTH
JDSU shows how to test a PON with an OTDR: http://www.jdsu.com/other-literature/PON-OTDR_fop_an_ae.pdf
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- Want To Learn More About FTTx?
- The FOA has created a special FTTx resources section of our website with a FTTx links page with lots of links to news, market reports, technical articles and vendor technical and product information. Here is a great place to start learning more about FTTx.
- FOA's CFxT FTTx Certification Program Explained
- Read the Broadband Properties article about the FOA FTTx certification program. Read the article about FOA President Jim Hayes being honored for his work promoting FTTH.
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