Sky (satellite) to a whole apartment block?

Aardvark

Bog standard apartment question... with a twist.

I can't stick a dish (Sky or otherwise) up on the wall (due to my apartment lease). But I'd like to know the options involved in whacking one up on the roof of the building and having it serve a signal to all the apartments (12). Then if anyone wants Sky Digital they'd just have to get a digibox from Sky. What are the options?

Does the box in the apartment block service area that NTL use to connect each apartment have any part to play in this? Who even owns that box?

Bonus points to anyone who can somehow get net service distributed via wireless lan in as part of the solution too!

carrolls

No. Every tv channel that you allocate for the flats will need a seperate digibox.

Aardvark

Originally posted by carrolls
No. Every tv channel that you allocate for the flats will need a seperate digibox.

Thanks carrolls,
It's an apartment block with 12 separate apartments. All I want to do is make the Sky Digital signal available to each of them. Like you said, if they want to use it they'd have to get their own digibox.

I'd like to do this by laying as little cable as possible. All the apartments are already serviced from a central cable point (a box in the service area of the apartment block). The problem is that I believe NTL own this box. (They certainly hold the key for it.) Even if we could get access to this, is it even possible to multiplex the sky digital signal with the NTL standard/digital signals without disrupting the existing NTL users?

dougal

I am not really sure of the technicallities here but my explanation of this is as follows.
Even with their own digibox as their is only one channel being tuned by the dish at a time (max 2 if you have dual lnb, not sure if this is how lnb works) it is only carrying one channel at a time so all the digibox could do is change the channels for all digiboxes.
this is part of the reason that NTL and Chorus still say that you can watch different channels in different rooms.

Aardvark

Originally posted by dougal
I am not really sure of the technicallities here but my explanation of this is as follows.
Even with their own digibox as their is only one channel being tuned by the dish at a time (max 2 if you have dual lnb, not sure if this is how lnb works) it is only carrying one channel at a time

Surely not? Either you're wrong, or my understanding of satellite broadcasting is WAY off! (Don't mean to sound rude - I'm certainly open to the possibility!)

I've a feeling the lnb picks out one signal from one satellite at a time, not one channel. Each signal includes the full range of channels from that broadcaster. i.e. one lnb picks up Sky Digital's full range (from that satellite). The digibox chooses which of the channels in that signal to decrypt/unscramble.

The reason you need two boxes to watch two channels is because each box will only decrypt a single channel at a time.

The reason you need two lnb's is to pick up signals from two different satellites off the same dish.

Anyone want to weigh in with corrections / more accurate description?

bucks73

Would three dishes with quad lnb's work? There would then be twelve different signals going to each digibox.

dougal

allright - I haven't a clue what I am talking about but I assumed that was the reason you couldn't watch different channels in different rooms.

carrolls

One decoder will only decrypt one channel at any time.
So if each apartment wanted a different channel, ie 12 different channels, you would need 12 digiboxes to realise this.
Also, correct me if I'm wrong but only one transponder on the satellite can be utilized at any one time on the same dish, so you couldn't, say watch RTE1 in one apartment, and BBC2 in another, if you are using the same dish, because they are on different transponders.

lawhec

Originally posted by carrolls
Also, correct me if I'm wrong but only one transponder on the satellite can be utilized at any one time on the same dish, so you couldn't, say watch RTE1 in one apartment, and BBC2 in another, if you are using the same dish, because they are on different transponders.

This would only be the case if you had a single output LNB (which you'd be mad to do!) but if you use a dual or quad output LNB these act like two/four completly independent outputs, allowing you to watch any signal from the same satellite e.g. output one feeds box one with Sky Sports 1 on it, box two UK Gold, box three MTV2 etc.

carrolls

I stand corrected, but what if the people from the 12 apartments wanted to watch 12 different channels on 12 different transponders, (Unlikely but possible scenario) this obviously wouldn't be possible from one dish,
would it?

lawhec

Originally posted by carrolls
I stand corrected, but what if the people from the 12 apartments wanted to watch 12 different channels on 12 different transponders, (Unlikely but possible scenario) this obviously wouldn't be possible from one dish,
would it?

It can be done. If you have one dish with a quad LNB, this can be fed to a distrubution circuit which can then feed a digibox in every single flat for example in London there are Sky distribution systems that can feed dozens or even hundreds of digiboxes from one dish with a quad LNB (the dish is usually slightly bigger than recommend for a single installiation. Global, who supplied the first TV link system and the ADX in the analogue satellite days (which allowed old receivers to pick up the 1D channels) do have these systems available. Tony may know better than I do.

In this case as 12 systems are to be fed the simplest solution would be to have three minidishes each with a quad output, 4 outputs from 3 dishes = 12 outputs.

byte

I am not too up on this scenario, but you would need a quad LNB with the four different outputs - Hor High, Hor Low, Ver High and Ver Low. These go to a block (not sure of the proper name at present) which the 12 boxes would have to be wired to and would be able to work independantly.

chernobyl

It depends on how much you want to spend on the system but this setup is completely possible.
There are 2 routes to take:

1) Buy a satellite dish that uses a focal line rather than point(Wave Torodial), and put 3 quads on it to feed each individual box.
This is an easy setup and pretty cheap.
Using a satellite dish with a focal line will cost you about €400 but they are only the size of a minidish and you will notice no performance drop during bad weather.

2) Very expensive....you have 2 quads feeding two STB's (these STB's are not "off the shelf" and will cost you some €4000 each) and from there you feed all channels into your own private cable system.

The cable system to avoid more cost will be an analogue system so your limited to channel choice but you get multi room viewing for free and macro busted for free too.

byte

Originally posted by chernobyl
1) Buy a satellite dish that uses a focal line rather than point(Wave Torodial), and put 3 quads on it to feed each individual box.
This is an easy setup and pretty cheap.
Using a satellite dish with a focal line will cost you about €400 but they are only the size of a minidish and you will notice no performance drop during bad weather.

I hadn't thought of that. That's a good idea.

RG59

use one of these ive used a couple of them. v good. made by triax.


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