Viewing 18 posts - 1 through 18 (of 18 total)
  • What fibreoptic thinggies are these?
  • gofasterstripes
    Free Member

    Got these from a skip – I want to use the boxes for a tiny NAS build, but before I strip them out, can anyone tell me what they are for and if they’re of any value.

    Also – what are the fuse-y thinggies in the junction between the coloured fibres? They look a little like encapsulated fuses, but in fibreoptic?

    Cheers!

    rogermoore
    Full Member

    Fibre Optic Patch Panels. The bottom ones (blue) are SC Connections and the Top Ones (with black caps on) are SC Connections. I take it the 2 are connected together? I wouldn’t have thought they were much use as they look to have been built up for a specific need. The fuse like boxes, I think, are where the fibres have been spliced together.

    Been a while since I’ve done much with Fibre, but think the above is right.

    RM.

    codybrennan
    Free Member

    +1 Roger.

    The ‘fuses’ are some proprietary fibre splicing bits.

    Cougar
    Full Member

    the Top Ones (with black caps on) are SC Connections.

    They’re ST connections I think.

    Even if they had a ‘value’, I wouldn’t want to use second-hand fibre unless I had a means of testing them. They’re fragile and who knows what state they’re in.

    scotsman
    Free Member

    the fuse-y things are a heat shrinkable protection sleeve that goes on after the joint has been fusion spliced.
    Top connector ST type
    Bottom connector LC type

    gofasterstripes
    Free Member

    Great. I’ll turn the fibres into a lamp or something and upcycle the boxes 🙂

    footflaps
    Full Member

    I wouldn’t want to use second-hand fibre unless I had a means of testing them.

    Anyone working with fibres will have a tester to measure loss / match etc.

    bearnecessities
    Full Member

    I think it’s a pair of 1210s made from silly string.

    Russell96
    Full Member

    Most likely the fuse-y things will be a mode conditioning patch where you can use a singlemode transceiver with multimode fibre, it will allow you to squeeze a bit more distance with multimode fibre links.

    docstar
    Free Member

    No Russell it’s a heat shrink to protect the splice.

    Russell96
    Full Member

    Why would you splice a 1 metre or so bit of fibre it would be easier just to put the correct connectors on both ends, its pointless splicing something for that distance.

    I’ve seen MCP’s just like that as I got bitten by them being deployed in an EoL Cisco estate with SC connectors (GBIC’s) wheras all the replacement switches were going to LC based SFP’s, the customer advised all of their internal cabling was multimode so alarm bells rang when I looked at their existing kit list and spotted all the LX GBIC’s >> http://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/prod_bulletin0900aecd80425a37.html

    Recovered in time and all the new patching correctly specced phew…

    Plus in a lot of cases Yellow is singlemode and grey is ye-olde multimode

    Cougar
    Full Member

    Anyone working with fibres will have a tester to measure loss / match etc.

    Anyone working professionally with them, yes. Our field engineers have fibre test kits. It’s not the sort of thing you find lying about in your average IT department next to the screwdrivers though, it’s expensive specialist kit.

    choron
    Free Member

    Knowing a decent amount about the general topic, I’m amazed at the level of knowledge on here. I have a couple of points: Second hand passive components are almost always worthless, that goes double if found in a skip. Testing, disassembling etc is always possible, but would be more expensive than buying new stuff from Thorlabs. A mode coupler is actually a pretty good suggestion, I’m not sure that you can get more distance from MMF fibre plant though – loss/km is pretty high for MMF, while the coupling loss going back to SMF can be massive (depending on the number of supported modes). I thought that the idea was more using SMF transceivers on installed MMF plant.

    Also, I have a question: How can you tell the difference between LC and FC from a distance? Same goes for the difference between SC and FC?

    Anyway, value of optics ~= 0.

    gofasterstripes
    Free Member

    I think I could have put it better at the start – I didn’t think for a minute that I’d found something likely to be worth a lot of money, and I wasn’t dumpster-diving with the intension of making monies from these [though I sure have at some points, and it’s worked 🙂 ] BUUUUT seeing as I know actually nothing about fibre it would be a daft suggestion to trash an item of unknown value and purpose. I know enough to know it’s fragile so I can’t just reach in and rip bits out and still be able to recover some value from them if I find out I should have saved it.

    Anyway – I now know what they were: A very small arena for a

    cheshirecat
    Free Member

    Looks like duplex LC at the bottom, ST at the top.

    Likely single mode fibre with the yellow jacket. Multi mode tends to be orange for OM1 or 3, and aqua for OM4. Single mode is 9 micron core, multi mode is 50 or 62.5 micron core. The stuff used in the Toslink system is 1mm plastic fibre.

    As to telling the difference, LC and SC are latching connectors, FC is screw on, and ST is an old bayonet connector.

    Value of the patch panel, pretty much zero. Unless your NAS has single mode interfaces, it’s not very useful to you.

    The distance limitation for high speed transmission (10Gbit/s) in multi mode fibre is modal dispersion rather than loss, but this is likely single mode.

    I work in fibre….

    gofasterstripes
    Free Member

    I seem to be having a serious issue getting my point across!

    I intend to use only the metal casing, it’s just thick enough for an SOC computer like a Pi or Galileo, a laptop PSU I have spare, a WiFI card and a few of my 3.5″ drives. I can even poke the aerial out of the cutouts in the back and then use the brackets to hang the thing under s desk.

    I have a load of music and movies on those drives, and my overclocked Core i7 uses 2-400W when running, so it’s daft to power it up just to watch a fillum.

    Seeing as I don’t want to waste useful parts or miss out on a few quid I didn’t want to trash the contents without knowing if they might be of use or value to someone.

    This is a very interesting discussion, yes 🙂

    Thanks for the help and brainwaves STW 🙂

    Doh1Nut
    Full Member

    I recon there is enough fibre there to light up you commuter like a TRON bike 😀

    Looking forward to photos

    gofasterstripes
    Free Member

    Not a bad idea – I may do just that 🙂

Viewing 18 posts - 1 through 18 (of 18 total)

The topic ‘What fibreoptic thinggies are these?’ is closed to new replies.