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Can You Build a Fiber Test Kit On a Budget?
An anonymous reader writes "Have any Slashdot readers hacked together cheap test kits for fiber optic cable? More and more IT infrastructure is using multimode and single mode fiber optic cabling. Commercial test equipment is extremely expensive, running the gamut from a few hundred dollars for a basic light source, to tens of thousands for an OTDR. What equipment do you consider essential to your fiber kit? Is there a way to save costs when it comes to fiber test equipment? It is worth it to do so?"
Two Media converters. If you can run ethernet over it, it's good.
Depends on what you need to do.
There are many different tests you can do on fiber. A basic college course will teach you that.
Do you just want to know if the fiber is not "broken"? a LED and a phototransister can do that.
Want to know if the fiber is the correct mode, optimized for the wavelength of the led, or can support multimode and run parametric tests on the fiber, gee, that gets more expensive.
Its the same for the DIY ethernet cable testers too.
Want to test continuity? a 5$ multimeter will do that.
Want to determine if the cable meets spec? You need better equipment.
Better Equipment GENERALLY equals better [test] results. [ yes, a lot can depend on the skill of the tech operating said equipment too].
"running the gambit" I don't think it means what you think it means.
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Had to answer this question once ourselves. Never got to the implementation phase, but the plan was to have one or two high-end test sets, and build the others out of the prototypes for the equipment we were building, and Lucent OptiStar NICs on Linux systems. IE, each protype would test the next, and we would have racks full of 1U Linux Boxen with Lucen OC-12 NICs. Can't find out of Lucent or Alcatel-Lucent is still making those things, but you can find used/refurbed OptiStar (?) SONET IP Nics for Linux (PCI) fairely cheaply. No idea if they work, but as low as $60 bucks. New, they were $10k to $6k. Searching for Optistar on Ebay or Google returns a lot of info. Or, searching for SONET PCI NIC. Or, just FIBER PCI NIC. You can probably set up a laptop with Gig-E, if you just want connection tests, regardless of which protocol you're going to use. Honestly, eBay/Amazon are your friends here. At times, you can find million-dollar test sets for $100 bucks (Adtech, Omniber, Cerjac...) Most are left-overs from when startups fail. Also depends on what you're testing.
Here's to losing my Karma Bonus again....
You can get these used on eBay all day long for a few hundred dollars for the entire set (search terms: "fiber test*" "fiber patch*" "fiber splice*"). You may have to watch a few days for a bargain, but I'm constantly amazed at how often high-quality fiber test gear goes for a song on eBay. Purchase only name-brand gear, such as Fluke, Noyes, Microtest, TestUM, etc. (You can learn the name brands by looking at new-equipment listings at places like CDW).
There are many tutorials on the web showing how to use these tools, most from equipment vendors themselves, and some are even high quality video presentations. A useful starting point is http://fiberu.com/ (although it's become less useful since Fluke took it over).
The mini-maglite will instantly identify any fiber -- the light will be clearly visible at the far end of even a thousand-foot run. If high-power IR lasers are in use on the network, be careful to be wearing fiber goggles whenever looking at fiber ends, even at your own white light. You can't tell when a fiber is energized with high-power IR, since it's invisible.
The power meter lets you measure the light loss through a fiber path, which when correctly interpreted will give you performance information. Get one that reads tenths of a microwatt, and that also directly displays dB loss from a reference signal. If you know the installed fiber specifications (you can read these off the fiber jacket), you can compute the available bandwidth based on fiber length.
The fiberscope reveals otherwise-invisible defects in a connector so that you don't spend hours trying to make an unworkable connection work. Again, be sure you're wearing laser goggles if you don't have both ends of a fiber in your hands. Magnifying harmful IR radiation is very dangerous.
For routine work you don't need an OTDR. Besides measuring the length of a fiber, an OTDR will locate defects along a fiber span so you can locate and repair them. If you're not repairing cable, or splicing it, an OTDR is overkill. Fiber installers have such gear, and they'll be happy to use theirs on your network for a fee when you need that capability.
There's a really cheap "laser" detector that nearly every tech carries, although you may have forgotten it.
It's that camera on your cell-phone.
Yup, in a pinch, you'll see a nice little purple dot appear on your screen if you've got IR coming down the fiber. Works well enough to identify active cables.
You can also pick up a mag-lite->fiber adapter that'll shine visible down the line fairly cheap.
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Bad moderator! No cookie! The parent is NOT offtopic. A flashlight works for a basic transmission test. I was a fiber optic technician in a former life and after terminating the ends with connectors we would shine a maglite on one end and turn out the lights on the other and if we saw the "light at the end of the tunnel" we'd call it good. If you want to get fancy you're going to need an optical time domain reflectometer. Probably not the cheapest thing.