Quick explination required on how NTL BB works

SachaJ

Right coaxial comes into the house and gets split two ways:

1. Analogue & Digital TV
2. FM

What happens with the BB? Does it now get split 3 ways? Or does the TV split get split again for TV and BB?

asmith

When I got NTL BB in I got a new point installed. This is just a standard NTL point with the usual two TV & Radio out sockets. The BB modem supplied by NTL just connects to the TV out. AFAIK there is no further splitting of the signal over and above the usual TV/radio. The BB signal is probably so high frequency that neither the TV not Radio radio waves interfere with it (or vice versa).
I plugged the modem into the existing TV point in the living room (an old Cablelink) one and it connected no problem.

Nietzschean

SachaJ wrote:

Right coaxial comes into the house and gets split two ways:

1. Analogue & Digital TV
2. FM

What happens with the BB? Does it now get split 3 ways? Or does the TV split get split again for TV and BB?

they install a splitter on your tv cable, lobsided to give preference to the cable iirc.....

thund3rbird_

http://www.ntl.com/locales/ie/en/athome/cm_installation.html

also diagram of installation if there is a dedicated point put in

causal

SachaJ wrote:

Right coaxial comes into the house and gets split two ways:

1. Analogue & Digital TV
2. FM

What happens with the BB? Does it now get split 3 ways? Or does the TV split get split again for TV and BB?

It only physically splits two ways as you say above: TV, FM.
BB occupies one 'TV channel', each channel is 6MHz wide, the cable can take about 150 channels. The cable modem splits out the channel required (well actually one for upstream and one for downstream); the upstream and downstream frequencies can be seen in the cable modem configuration screen.

hth,
causal

Gone West

It depends on your connection. Some high speed cable bb (like mine 5.5 mbit) uses 8 channels to send recieve.

causal

FuzzyLogic wrote:

high speed cable bb (like mine 5.5 mbit)

:eek: :eek: Well now just where in the hell are you getting that, and how much of course!!
Please say you're doing a trial for ntl ahead of their highly anticipated announcement

causal

tomk

FuzzyLogic
Registered User

Join Date: Jan 2005
Location: Abroad For A While
Posts: 550

Infini

I think on one of his previous post Fuzzylogic said he was in America.

RicardoSmith

causal wrote:

It only physically splits two ways as you say above: TV, FM.
BB occupies one 'TV channel', each channel is 6MHz wide, the cable can take about 150 channels. The cable modem splits out the channel required (well actually one for upstream and one for downstream); the upstream and downstream frequencies can be seen in the cable modem configuration screen.

hth,
causal

My NTL modem only works on the port they installed for it. On the other point where theres a TV it doesn't work. Why is this?

causal

RicardoSmith wrote:

My NTL modem only works on the port they installed for it. On the other point where theres a TV it doesn't work. Why is this?

That's peculiar. I know others have posted on boards that they have been able to use their cable modem on other tv points in their house.

When mine was installed the guy replaced my old box (I already had cable and a tv point). I asked him what was the difference with the new box (apart from being hidesouly large and a horrible shape) and he said it had surge protection.
I thought that was odd because all the cable in my neighbourhood is underground, so it's unlikely to be hit by lightening, and the cables don't carry a 'power'ful current. Plus I'm sure they have surge protection protecting their own outside equipement.

In any event, lack of surge protection shouldn't stop it working. I had then thought that maybe the new box has something to allow 2-way signalling; but then others have said they can use normal catv points for boradband.
Is the catv point that doesn't work for bb poorly wired or a long distance from where the signal enters your house?

causal

cregser

RicardoSmith wrote:

My NTL modem only works on the port they installed for it. On the other point where theres a TV it doesn't work. Why is this?

I'm kinda guessing here. Assuming the broadband operates at higher frequencies than the TV signals, they probably installed a low pass filter for the TV port. Meaning anything connected to the TV port can't see the BB frequencies. They probably did this to prevent noise from the broadband interfering with your TV signal and vice versa. But that's something they shouldn't HAVE to do, but "good practice" at the same time. i.e. the technician was probably going by the book,

causal

Worth a guess cregser but not accurate in this case:

BB downstream ~ 400MHz
BB upstream ~ 200MHz
...
TG4 208 MHz
BBC 1 216 MHz
...
CNBC / Pay Per View 408 MHz

Cable broadband fits into 6MHz slots that could otherwise carry tv signals.

causal

RicardoSmith

The BB point is upstairs. Whereas the TV point is downstairs and closer to the signal box. There wouldn't be much in the difference in the distance to be honest. If theres a filter on the box that would explain it. To my untrained eye theres nothing obviously different about the boxes or in the signal box. Moving the BB around isn't a problem since I use a wireless router. But it would have been nice if I could have got TV beside the computer.

As for surges they can come up your electricity lines and jump to nearby wiring. Such as telephone lines and TV cables. My telephone and TV points are all beside sockets.

causal

RicardoSmith wrote:

As for surges they can come up your electricity lines and jump to nearby wiring. Such as telephone lines and TV cables. My telephone and TV points are all beside sockets.

But the beauty of coax cable is the insulation provided by the 'Faraday cage' wrapped around it, so it's (mainly) immune to electrical interference.

You should still be getting the tv channels from the box that was installed for bb. You'll need a splitter, with the side-effect is a decrease your signal strength, but you should be able to watch tv at the broadband point. I do.

Isn't there an ntl tech on boards.ie - come on tell us what's the story with these magical boxes ...

causal

chorus techy

causal wrote:

I thought that was odd because all the cable in my neighbourhood is underground, so it's unlikely to be hit by lightening, and the cables don't carry a 'power'ful current. Plus I'm sure they have surge protection protecting their own outside equipement.

And the cable equipment gets its electricity from the public utility electricity system. What if lightning was to strike, say, a lampost? And believe, the cables can carry enough current to cause any STB / Cable Modem / TV / VCR to overheat, catch fire and burn your house down in a matter of minutes!

causal

Thx for enLightening me (bad pun ) chorus .

Do you know if that is the only difference between the catv point ntl install for broadband, or is there something else in it?

Thanks,
causal

chorus techy

causal wrote:

Worth a guess cregser but not accurate in this case:
BB upstream ~ 200MHz

BB upstream is between 5 - 60 Mhz, this is because ntl is built according to the "DOCSIS/EuroDOCSIS" (techy terms) standard. It is also the reason NTL (and other cable providers) have such limited upstream speeds due to a simple lack of space. Bit crazy and short sighted of whoever set the standards :rolleyes:


As for the ntl CATV points - I'm only guessing here, but I'm imagining that they install a "blocker" to restrict the TV signals - this is so you only receive broadband signals through (as this is all you are paying for - additional TV points cost €2.38). Because additional TV points costs €2.38, I doubt you'd be happy to be told your lovely 700k €35 connection actually costs €35 + €2.38!

Aquos76

AFAIK they have done away with the additional charges for extra points. I stand corrected though....

RicardoSmith

Leonard wrote:

AFAIK they have done away with the additional charges for extra points. I stand corrected though....

I'm still getting charged for them !!!! :mad: have to get on to them about it.

chorus techy

Leonard wrote:

AFAIK they have done away with the additional charges for extra points. I stand corrected though....

You're not serious! I'm being charged the best part of €5 per month to have two additional points around my house! AFAIK, they *may* waiver this €2.38 if you get the additional points with ntl digitals package (I have sky and ntl basic).

Aquos76

Well it looks like I may be wrong. Up to Jan 2005 I was paying for 2 additional points and then all of a sudden they dropped off my bill and I now just pay the standard €19 for the basic cable. I just assumed that they had done away with these charges (actually this is ntl we are talking about, why whould they do that)

http://www.ntl.com/locales/ie/en/athome/tv.html

Lenny

RicardoSmith wrote:

My NTL modem only works on the port they installed for it. On the other point where theres a TV it doesn't work. Why is this?

Thats the same as myself, when getting it installed he ran a wire from the neighbours grey 2 socket box on the front of their house down mine and into the garage were he made a point. he told me the reason for this was because the other points in the house were old and he needed a rj45 version box, while the others were rj40 and wern't any use for the cable modem.
Now that they also removed their telephone system and put another new installed pointbox in my bedroom I may try that to see if that works for the cable modem too.

RicardoSmith

chorus techy wrote:

You're not serious! I'm being charged the best part of €5 per month to have two additional points around my house! AFAIK, they *may* waiver this €2.38 if you get the additional points with ntl digitals package (I have sky and ntl basic).

I was thinking how does the multi-room viewing option happen if you've no extra points. Or if you already have them.

bk

I just got NTL cable BB installed yesterday and three NTL Digital Boxes.

They had to install two points for two of the Digital Boxes (there was no points there before).

The cost per month are:

€50 for BB (first 3 months free).
€10 for first digital point.
€5 for each aditional point (There is no additional charge for these points).

Installation and equipment for all of this was free.

They are also giving us free basic analog TV for 12 months (you usally have to pay €19 per month for this).