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Posted By: jeffmoss26 CATV question - 07/27/14 01:41 AM
The office building my friend manages recently had cable TV installed from the street and into each phone room. I'm not really familiar with their outside plant stuff, so I was confused when I saw this cable running through the building. There is no plastic jacket, it's just aluminum (I think).
Perhaps Hal or someone who knows more about the CATV industry will chime in.

Jeff
First floor, from entrance in the basement through the garage and up-
[Linked Image from i1246.photobucket.com]
Second floor closet
[Linked Image from i1246.photobucket.com]
This floor closet (end)
[Linked Image from i1246.photobucket.com]
Posted By: EV607797 Re: CATV question - 07/27/14 04:57 AM
It's legit, Jeff. Being non-jacketed, that cable poses no fire spread risk. Believe it or not, prior to the development of plenum-rated cable, we got our 25 pair cable delivered the same way: A hard outer aluminum tubular jacket with a traditional twisted pair cable inside.

Talk about a pain in the ass to run and terminate!
Posted By: Silversam Re: CATV question - 07/27/14 01:24 PM
Yup. What Ed said. When fire resistant cable was first required we found ourselves putting in all sorts of stuff - aluminum clad cable among them. I did one job with aluminum clad 25 pair and quad. What a PITA!

And yes, here in NYC the cable companies will use aluminum clad stuff for risers/feeders/whatever - sometimes. Doesn't seem to be a rhyme or reason - maybe they just use whatever's in the warehouse at the time....

Sam
Posted By: jeffmoss26 Re: CATV question - 07/27/14 02:24 PM
Wow, never heard of aluminum clad phone wire (except for the rodent shield on OSP stuff)
Time Warner did a halfway decent job on this install, I guess. Backboard space is a premium due to the cluster in those phone rooms.
Posted By: mbhydro Re: CATV question - 07/27/14 03:41 PM
The distribution install looks good because it was probably done by a staff installation crew.

Just wait a few years until the piecework installers get in there and have coax going all over the place.
Posted By: hbiss Re: CATV question - 07/27/14 05:08 PM
Yup, that's plenum cable. smile And nice job by the way.

-Hal
Posted By: Telxonator Re: CATV question - 07/27/14 05:27 PM
It does look good. I've seen our local cable co. use RG11 to supply a neighborhood because a section of hardline was bad. Ran it along a privacy fence and heaped the extra slack at the ground. someone hit it with a mower, so cable co just splices it back and leaves it laying.
when they finally fixed the hardline several weeks later (was cut again) they left 200'+ of direct burial RG11 laying in the bushes, so obviously I retrieved it. was told by fellow ham radio ops it can be used on antenna stuff even though ham radio uses 50 Ohm and CATV is 75 Ohm.
Posted By: jeffmoss26 Re: CATV question - 07/27/14 09:13 PM
The ceilings are stuffed in this building, I am SURE the installers don't carry plenum RG-6. Will be interesting to see the end results.
Posted By: WiringSolutions Re: CATV question - 07/28/14 01:20 AM
Was mighty nice of them to leave all those spigots unterminated for you lol. I guess they don't worry about ingress on their plant there.
Posted By: jeffmoss26 Re: CATV question - 07/28/14 11:20 AM
Yeah I did notice that!
In the other building he manages, the taps are in locked enclosures with those funky tamper proof screws that the cable company likes to use.
Posted By: Rcaman Re: CATV question - 07/28/14 05:09 PM
It looks like AME412. That's the same cable they use OSP. There is no rhyme or reason why they run some like this and some with insulation.

I think the first "fire retardant" telco cable was lead sheath. laugh It didn't burn....but the contamination was another thing. doh In Pittsburgh, there is, literally, thousands of pounds of lead sheath cable still in use as OSP, in building riser and protector tails.

Rcaman
Posted By: jeffmoss26 Re: CATV question - 07/28/14 05:48 PM
I found a few items on Commscope's site:

https://www.commscope.com/catalog/broadband/2147483659/product.aspx?id=16&sort=null&nrp=null&ShowObsolete=false&filter=2786|7||0||
Posted By: jeffmoss26 Re: CATV question - 08/03/14 12:23 AM
Here's the first drop install. I am guessing that is a filter on the tap.
[Linked Image from i1246.photobucket.com]
Posted By: EV607797 Re: CATV question - 08/03/14 03:32 PM
It is probably an attenuator, Jeff. The signal was likely a bit hot, so they often tune it down a bit.
Posted By: Mercenary Roadie Re: CATV question - 08/04/14 06:57 AM
Originally Posted by EV607797
It is probably an attenuator, Jeff. The signal was likely a bit hot, so they often tune it down a bit.

The standard attenuator is smaller. the 14dB output of the drop is definitely not too hot.

The cable companies use various types of filters on the drop boxes. Some are there when cable modems are used and they put them on the outputs without the modem. Some use to be used to filter out the digital signal when only the analog signal was needed, etc, etc.
Posted By: jeffmoss26 Re: CATV question - 08/04/14 01:38 PM
Buckeye Cable in Toledo always seemed to use filters on their modem lines.
I rarely see them used with Time Warner but maybe since this is a business account something is different.
Posted By: Rcaman Re: CATV question - 08/04/14 02:07 PM
Comcast business drop feeds here are usually around 50 db and that device is the exact size of the attenuators used by Comcast here. Comcast has been trying to work with business to wean away FiOS customers and the puny signal that they provide for homes doesn't cut it for business. The one big problem they can't seem to resolve is bandwidth and multiple users. They will tell the customer they have 100/50 Mb Download/Upload but when there is 10 or more users on the circuit, they may get 20/3 Mb and it gets worse with more users.

Rcaman
Posted By: Mercenary Roadie Re: CATV question - 08/05/14 12:32 AM
The numbers on the colored background on the drops are what each port put out in dB. I'm sure there is a main amplifier somewhere in the system (big silver box with multiple cables). The need for attenuation is not required in this case.
Posted By: ChrisRR Re: CATV question - 08/05/14 01:47 AM
The numbers on the tap blocks indicate the dB drop of the tap. As in a tap labeled 17 has a 17 dB drop from whatever the main feed is at. That's why, as the run continues, the number drops. The taps have less of a drop to accommodate the signal weakening along its length.
Posted By: jeffmoss26 Re: CATV question - 08/05/14 11:43 AM
There's no amp that I could see. Hardline runs from the pole, underground, into the building and into the first floor phone room (taps in my first pic)
Posted By: Mercenary Roadie Re: CATV question - 08/06/14 01:57 AM
Originally Posted by jeffmoss26
There's no amp that I could see. Hardline runs from the pole, underground, into the building and into the first floor phone room (taps in my first pic)

Then the Amp is probably out on the pole unless there is a green hand vault along the path that it might be in. There will be an Amp though
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