On 7/10/13 6:55 AM, Art Greenberg wrote:
On Wed, 10 Jul 2013, Jim Lux wrote:
they clearly make preterminated outdoor suitable cables, because
that's what the Verizon FIoS guys use when doing installs.
I'd have thought that Verizon could afford to terminate on site. Or at
least make their own assemblies for use in field install.
They're more interested in speed of install, so they carry a whole batch
of preterminated cables in various lengths on the truck. They pick the
one that is the right length, pull it through the underground conduit
alongside the copper that's already there (a non-trivial task in some
cases), coil up the excess on both ends, hook it up, and they're done).
That way they don't need all crews trained in doing the connectors, etc.
David did point to one on-line shop that does, which I missed. They
don't give pricing on line, but claim a good selection and even offer to
install a pull eye. I'll have to call them.
Yes, if you installed 1/2" conduit, it's not going to be easy to find
a terminated cable that will fit.
That said, the connectors on the end of fiber are sort of about the
size of an SMA connector. If you can pull coax with a PL259 on it
through the conduit, then the fiber should be possible.
Its a 1-inch SCH40 conduit. It was put in many years ago by the previous
owner of the property, and had been used to run power to the barn. I had
a new, separate service installed, so I pulled the wires in anticipation
of using it for something else. When I pulled the wires out of it, they
were just a little wet.
Probably almost anything will work. A bit wet is normal just from
condensation. I don't know what the degradation modes are, but it's not
like you're worried about the copper oxidizing or corroding.
L-com has a 50 meter duplex 62.5/125 cable with ST connectors for $77.
The ST connector is pretty small. That's for a OFNR (riser) type cable.
Most of the outdoor cables I've seen have been more strands, though (6
or 12 seems common). I think that's because in most situations, the
glass cost is small compared to the labor cost to pull the cable, so
you might as well pull 12 and use 2, leaving 10 dark.
Hence my concern over pulling a preterminated cable. High strand count
and perterminated probably means expensive, too. And I really would feel
awful to cut off perfectly good terminations.
The preterminated cables tend to have just 2 fibers and look a lot like
skinny orange zipcord.
If you're pulling lots of cables for infrastructure, then they use the
6/12/24 fiber versions. Over the past few years, they must have pulled
miles of the stuff at JPL as the network infrastructure is gradually
upgraded. Those are typically field terminated.
It also depends on what your standard of performance is. Maybe indoor
cables will work just fine in your conduit, even with the water. Or
maybe you'd have to pull new cables every 10 years or something.
I'm very curious about this. I'm going on information from one source
who does this type of work.
The cable is obviously protected in the conduit, so I *think* the only
concerns are pull tension and the possibility of small amounts of water.
pull tension is carried by a non-stretchy nonconductive strength member
in the cable (Kevlar, Spectra).
Fiber is great, and as the cost of preterminated cables keeps coming
down, it's more and more attractive. When consumer gear starts coming
with optical connections, I'll be happy.
The challenge, as you've found, is finding the suppliers of this kind of
thing. Finding bulk cable is easy. Finding inexpensive terminated
cables and stuff related to that is tougher, but they're out there.
Depending on your location, there are also lots of small contractors who
do fiber installs these days. The challenge there is that the minimum
job cost is probably a bit high for the average ham install. It's just
the economics of the situation: it's hard for a small company to take a
$100 job, because they'll burn that just in gas and labor getting
to/from the job site.
If you can piggyback your job onto a bigger one, that can help, but that
basically requires knowing someone who's doing it.
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