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medicaltech
18-07-2005, 13:26
I havenââ‚ƚ¬Ã¢â€žÂ¢t had cable installed before, so if the following question seems idiotic sorry! ;-)

You have a single cable coming down your drive that will connect into the back of a cable box and that provides the TV †“ so far so good †“ so where do the telephone and broadband connections come from? †“ the back of the cable box I assume? What is stb that I see people refering to?

Chris
18-07-2005, 13:35
:welcome: to the forum.

The single cable comes down your drive and attaches to a box on the outside wall of your house. The various services you take from NTL branch off from this box. Cables emanating from this box on my former house terminated in three boxes on inside walls - one of them a phone socket, and two for broadband or TV.

A STB is a Set Top Box - coaxial cable is attached to the wall box inside your house, then to the STB, and the STB is attached to your telly. The STB decodes the TV transmissions that come down the cable. You leave your TV tuned into the same channel at all times, and change channels on the STB in order to watch the various channels NTL provides.

Stuart
18-07-2005, 13:45
Further to Chris's post.

When you get cable installed, NTL or Telewest will install two sockets on the wall. One is a standard BT style phone socket, and you plug the phone into this. The other is the socket for your Cable TV and Broadband. The Engineer will plug your set top box and/or cable modem into this.

An STB (or Set Top Box) is basically a low powered computer that is designed to decode and display cable TV and/or provide a broadband connection . The STB also provides a limited web browser, and software for enabling Interactive TV.

As I said earlier, it can also, optionally provide a Broadband Internet Connection. This depends on your supplier and area. I believe Telewest always use an STB to provide the broadband connection, with NTL it may or may not be optional, depending on your area. So, with NTL, in some areas you get broadband through Cable Modem and some areas get broadband through STBs.

Cable Modems (also called Stand Alone Cable Modems, or SACMs) provide a Broadband internet connection. Depending on your setup, you may have a Cable Modem as well as a Set Top Box. In this case, the Broadband connection will come through the Cable Modem, and not the STB.

Dave Stones
18-07-2005, 13:51
just to be pedantic, but telewest give out motorola SB5100 surfboards now as standard too :)

Chris
18-07-2005, 13:53
just to be pedantic, but telewest give out motorola SB5100 surfboards now as standard too :)

Dave ... just to be pedantic, like ... if you, like the OP, had absolutely no understanding whatsoever of Cableco services .... what would you understand it to mean if you heard a company was giving out surfboards? ;) :D

Stuart
18-07-2005, 13:57
For some strange reason, I just thought of a load of "doods" on the beach, listening to beach boys songs..

Just to make it clear to the Original Poster: A Motorola SB5100 surfboard is a particular make and model of Cable Modem.

Jules
18-07-2005, 14:03
I thought Dave was taking the pi....well just to say I didn't think he was being serious. Thanks Stu for clearing that up :tu:

jaycee
18-07-2005, 14:05
Telewest give out stand alone cable modems in all engineer-installed situations, usually either Motorola Surfboard 4100/5100 or SciAtl Webstar modems. (The Motorola ones are the best, BTW :))

They do, or used to do, a service called "Self-Install" where, if you have had an STB already installed, they will activate broadband (up to 1MB I belive) and leave you to connect your computer to the Ethernet connection on the back of the STB. They would also offer a wireless tranciever kit in case using a cable wasn't feasible.

medicaltech
18-07-2005, 14:15
Thanks for the quick replies!

Now more questions! From the box on the outside wall I assume that there will be 3 cables coming out: 75R coax to the set top box, standard 6 core BT cable to the phone socket, and XXX? to the cable modem (what type of cable and how is it terminated? direct into modem or via a socket?)

I only ask because I would prefer to do most of the internal wiring myself before NTL turn up, as I don't want cables run around the skirting, drilled through door frames etc.
Ideally I would like the 3 cables to go into the loft and then down into the relavent rooms via the cables I have already put in in-between the walls (house is wired with video distribution system via loft and telephone extensions are also accessable via loft). The only thing I would have to run is a cable down to the room where the computer is (hence I need to know how it terminates)

Stuart: re:broadband connection, area is Manchester, NTL

jaycee
18-07-2005, 14:23
The cable from the street is typically terminated in a brown box on the outside of the property. The "drop" as it's called is usually a multi pair cable for phone line(s) and a single RG58 coaxial cable. This is then split as required using splitters to run multiple points. Cable modems accept an RG58 feed the same as the STB does. In some cases, they will use more than one co-ax "drop" usually if the cable is too long or unable to run more than one device at once.

Sadly most telecomms companies will not connect to your own wiring (except for phone lines). This is because cheap coaxial cable/satellite cable doesn't usually work all that well for the high frequency signals that CATV systems use. This leads to SNR and signal level problems later on.

For the computer, you may be best running a CAT5 ethernet cable wherever you want it to go, and then have the cable modem sited near a coax point. Or have them use your STB for internet, so you will only need to site one coax point and one phone point. Run a cable from your phone sockets to wherever the entry point on the house will be, ie where they will be siting the master socket.

marky
18-07-2005, 14:54
NTL drill holes and fasten cables :woot:

they just gave me a 10 meter ethernet cable and loads of coax coiled up behind the tv and didnt fasten the internal coax box to the wall
the only thing they did fasten was the telephone right were the cable come through the wall
just ask the fitter most are nice guys
oh and :welcome:

jaycee
18-07-2005, 14:56
Was that NTL own installers, or a subcontractor?

marky
18-07-2005, 15:33
Was that NTL own installers, or a subcontractor?
got me there i honestly dont know but i bet they will its less work and you can only ask nicely:LOL:

Chris
18-07-2005, 15:39
Same happened at my house, as it was a terrace, the computer was in a back room, the cabled street was at the front and he refused to go in the loft or sling the cable over the roof. He set it up with enough cable for me to it myself and left me to drill holes and tack to the wall. (well actually he didn't, the cable length was too short and he had to come back later with more, but it's the thought that counts! :D ).

edit

that is, tack it up the wall, through the loft and down again - he would have done skirting boards but I didn't fancy having a massive cable snaking right round the house!

spike7451
18-07-2005, 16:11
We also use RG-6 internal cable, Black & white.The tv,sacm connections are smap'n seal 'F' type screw on connectors.
Standard tv catv is,as said above,cr1p! you lose too much signal,cause interfearance to leak onto the network & our 'F' connectors dont fit on properly.
Best bet,Next time you see a NTL van,grab some cable off him & run it yourself,just leaving enouh at each end to make off the connections,say about 1 to 2 meters.
Spike

medicaltech
18-07-2005, 17:28
I take it FT125 LL Sat cable would be ok? (Thats what I used for the distribution system and I have a fair bit left over). Are NTL master sockets the same as BT master sockets?

spike7451
18-07-2005, 18:09
I take it FT125 LL Sat cable would be ok? (Thats what I used for the distribution system and I have a fair bit left over). Are NTL master sockets the same as BT master sockets? Not really,I've found in the past that you can lose too much signal and our 'F' fittings are.not as secure as they are on ours.Also,if you run the Sat cable & you then run into trouble,it'll have to be changed AND you'll probably be charged £50.oo for the trouble.Reason is basically,all equipment is property of NTL (in the T & C's) & if you run your own stuff,it's not covered by NTL so if it goes wrong & has to be replaced,because it's not NTL fitted,it's ,well,not our problem (to put it bluntley!)
NTL master sockets are the same as BT's but if your thinking of swapping BT's for NTL's we cant.We have to leave BT's service to the master point in-place.Any extensions beyond that we can wire into our 's.But the installer will have to mount a new Master for NTL.
Spike

greencreeper
19-07-2005, 00:01
On the subject of holes and NTL - they make a mess. I gave them a fresh plastic dust sheet and somehow they missed it completely and covered the carpet in brick dust instead :dozey:

I thought the broadband and TV services used the same cable but different frequencies :erm: