Diving in - tips and tricks?

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Hmm. This group appears to be it for fiber on usenet? Hope I won't
offend with content that may belong more in comp.lan.fiber (but it does
not exist) or sci.fiber.basics (ditto - but I really think I've got the
basics rammed in - still what I'm actually doing is pretty basic.)

Oh, and - Hi Phil. Hope the rack is working out.

Dragging a school LAN into the late 20th century. Balkanized (3
separate) copper networks. Trying to get to a gigabit (for now) fiber
backbone all over campus. Starting from scratch, fiberwise. Looks
possible that the powers that be are going to vote for in-house and less
cash out of pocket, given the state of the economy and in-house labor
that's not afraid to go there (I'm with H. Ford on that one - I think I
can, so I'm probably right.)

Started out thinking I was going multimode and OM3 so I'd have 10Gig in
hand for the future, then found $49 list price SM SFPs and the savings
on fiber (a couple of kilometers, total) overwhelmed the "prohibitive
price of electronics" (lighting at 1Gb in either case - will await lower
prices before heading to 10 Gb) that was the assumption leading to MM in
the first place.

Having no installed base to conform to and being on a LOW budget I have
the following general ideas in place. Thinking to take my indoor/outdoor
(no splices, no junctions) distribution cables to locked cabinets that
will be large enough to house the electronics, rather than the typical
"fiber patch panel wall box" or equivalent rack unit. Patching is not
really an issue here - might happen once in 5 years. Thinking to put
something like a CCS spider breakout on the end of the cable, along with
20 feet or so of service loop, fastened to the inside of the box, and
skip the whole patch panel, patch cords, etc. expense - and the
associated optical losses. Terminate to LC connectors, stuff into SFPs,
turn distribution cable into long bundle of patch cords between my
switches. SFP Xmit - LC - distribution cable - LC - SFP Rcv

I've had claims that if the fiber is 900um tight buffer I might not even
need the breakout kit, but if it makes it more robust, it's not too much
of an expense - on the other hand, the whole point of the locked box is
to keep the ignorant out. I don't have a feel for how subject 900um is
to expire when handled by non-idiots, and rarely. I'm now also looking
at a 250um product, and there most of the available fan-out products
(not all) are only getting it up to 900um - so is it worth the expense
and extra shopping hassle of hunting down 250um to 2 or 3mm product, or
is 900 um and not handling it like a doofus likely sufficient?

The benefits (if any) of a patch panel and patch cords come at a large
cost for my application - more than the whole 2km of fiber, actually.
The only time I see unplugging anything would be when 10Gb SFPs become
affordable, or in the probably rare instance that one fiber goes bad and
we need to switch to a backup fiber (where I think the more typical
problem is all fibers got broken by a mad backhoe and I rent a splicer
as fast as possible.) Other than that, it would be to replace things
(SFPs or switches) gone bad. That's it.

After quite a bit of reading, and between the lines reading, and
considering that I used to polish the ends of laser rods with a puck 20
odd years ago, I'm inclined to epoxy polish connectors. The labor is
already paid for, the connectors are much cheaper, I have a good
starting kit of abrasives courtesy 3M at the NFOC and there's nothing to
go wrong later as there is with the various mechanical splice connectors
everyplace is trying to sell as quick and easy. Nor do I have anything
like the budget for a fusion splicer (even the rentals are terrifying),
and that type of splice on connector is still far more expensive. One
thing I do find confusing is that I can find mention of a clever Corning
spring-loaded LC polish puck, and a part number, but I'm danged if I can
find anyplace actually selling it, including places selling Corning

I need to do about 100 connectors - I figure I get 150 and plan to throw
the first 10-15 away on learning curve issues, plus a loss percentage on
the rest.

LC connectors appear to make the most sense with no installed base to
conform to - it's what all the SFPs I want to plug directly into take,
and they have generally lower loss numbers than the bigger connectors.

Thought - tips - tricks - advice - donations of piles of LC connectors
or other goodies all accepted (private non-profit high school with tiny

Final observation from me - it's amazing how much you can charge for a
$5 laser pointer when you call it a visual fault locator...

Cats, coffee, chocolate...vices to live by

Re: Diving in - tips and tricks?
Ecnerwal wrote:
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Hi, Lawrence.  It's just about full of classic HP and Tek gear at the
moment.  From the top down:

HP 3325A synthesizer
HP 8540B synthesizer
Tek 11802 20 GHz sampling scope
Tek TDS 744A 2 Gs/s digitizing scope
HP 35665A Dynamic Signal Analyzer
HP 8568B spectrum analyzer
Keithley 410 Micro-Microammeter
HP 339A Distortion Analyzer
HP 8620C Microwave Sweeper

Sometime around Wednesday it'll also have a very shiny 200 (peak) Gflops
dual 12-core AMD processor number crunching machine with 64 GB of memory
and a bunch of disc storage, mounted down around ankle level because
there's no other space left.

So you could say it went to a good home.  If you feel like mailing me
the side covers, my wife would be happier. ;)

I'm not a fibre installation guy, so I'm not much use on the rest of it,
I'm afraid.  I think you're right about polishing your own fibres though.


Phil Hobbs

Re: Diving in - tips and tricks?

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They are nice, aren't they?

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 I think I only have one anyway, and it would be hard to mail. If you
don't need the the shielding that metal would provide, I think sheets of
Formica or equivalent (I'd lean to a nice faux-granite, you pick the
pattern your wife approves of) would slip in just dandy. Get the
lumberyard to cut them to size. Stick aluminum foil to the backside for
just a hint of shielding if you feel the need...but for wife approval  
they should do the trick.

Cats, coffee, chocolate...vices to live by

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