Virgin Media Box: Class Act

In cam.misc tony sayer wrote:
Co-ax, RG11 IIRC and a two pair copper phone cable often referred to in
the trade as "Sidecar cable"

Yup, that was what NTL fitted us in 2003. I don't know what Cambridge
Cable themselves installed, but I assume it was the same.

Theo

tony sayer wrote:
In article . org
, Malcolm Gray scribeth thus

at my daughter's house there is only 1 cable incoming which is then split
to provide telephone & television. So, they can't all be like that.

that is how I remember it from my friend's Cambridge Cable. One coax, a
magic box, then cable modem on one socket and a standard BT style phone
on another.

I should cross post this to cam.misc as they are all on it over there.
My memory is of a figure of eight cable that was something like coax and
cat 5.

Co-ax, RG11 IIRC and a two pair copper phone cable often referred to in
the trade as "Sidecar cable"


Right: Given that it's you Tony, I take that as authoritative.

So instead of using - say - baseband POTS and RF muxed on the one cable,
they run a separate pair for de dog and bone..but in the same sheath?

Mark Carver wrote:
On 08/02/2011 19:44, Mark Carver wrote:

Thanks for your concern chaps, the enhancements from Rick and Peter are
very good, but just as you can't beat having more signal in the first
place, rather than trying to boost it, I will take a new shot tomorrow
morning, with the fine example of telecommunication engineering
excellence, glowing in early morning Hampshire sunlight.

...well, morning drizzle, but here it is:-

http://www.markyboy.net/vmbox3.jpg (1 Meg)


I've sent this picture to the National Gallery of Modern Art, and told
them that you can do the actual museum installation next week. If Damien
Hirst and Tracy Emin can do it so can you. The working title of your
exhibition will be '21st Century British Workmanship'. Could you get a
few other minor exhibits together -- a few botched air cond jobs or
something?

Bill

Malcolm Gray wrote:
at my daughter's house there is only 1 cable incoming which is then split
to provide telephone & television. So, they can't all be like that.

that is how I remember it from my friend's Cambridge Cable. One coax, a
magic box, then cable modem on one socket and a standard BT style phone
on another.

I should cross post this to cam.misc as they are all on it over there.

My memory is of a figure of eight cable that was something like coax and
cat 5.

Round here they run a single RG6 into the premises and fit a small
screened splitter on the end. One leg does the telly; the other does the
phone.

Bill

Bill Wright wrote:
Mark Carver wrote:

...well, morning drizzle, but here it is:-

http://www.markyboy.net/vmbox3.jpg (1 Meg)


I've sent this picture to the National Gallery of Modern Art, and told
them that you can do the actual museum installation next week. If Damien
Hirst and Tracy Emin can do it so can you. The working title of your
exhibition will be '21st Century British Workmanship'. Could you get a
few other minor exhibits together -- a few botched air cond jobs or
something?

Ah, er, how about this:- ?

http://www.markyboy.net/aircon.jpg


--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

In article , says...


Erm, I am confused. Maybe not in your area but here VM (formerly
NTL, formerly Bell Cablemedia (I think)) have fibre feed to the
street cab and a paralleled pair co-ax/four-pair to the house.
The co-ax carries TV and broadband, the pair carries telephone.


My understanding certainly was that there was fibre to the cabinet, and
coax and/or UTP from there to the premises, depending.

Cambridge cable presentation (now Virgin via NTL) IIRC is /was pure
coax. With phones demuxed of that somehow. I think.

Fibre to the distribution cab than demux to subscriber cabs and those
are copper and co-ax around up to 1 km or so max from what I remember of
it..


Actual reach depends on a number of factors - not least the number of cascaded trunk
amplifiers permitted which, to a certain extent, will be supplier dependent.

If the fibre node is in the middle of a built up area, the RF may split 5 or 6 ways at
that point. As the distance from the fibre increases, the area to be covered on each leg
expands in a triangular fashion so the signal continues to split into multiple branches.

The passive loss of all the splitters eats into the budget considerably. The loss of one
three way splitter, for example, represents around 100m of standard trunk cable.

One amplifier I'm familiar with (Teleste DXT 802) had a gain of ~25dB (@ 862MHz). Maximum
casade was three (plus a Line Extender)

1km of standard trunk cable (Commscope QR540) has a loss of 66dB @ 865MHz, so the
distance would be achievable if it wasn't for the chore of feeding all the customers on
the way ...

In practice, in most circumstances the design would run out of steam long before that.

--

Terry

In article ,
says...

In article , Terry
Casey wrote:

[Snip]

The operative word there is SPLIT - as in 'splits into TWO separate
cables ...'


The box seems very big just to do this.


I assume you mean the box inside the house. How big is it?

If you consider the CATV and 'phone separately, the Master Socket for the latter needs a
single outlet box to itself.

The CATV feed has to be fitted with an isolator and the drop cable needs room to turn
round, so that usually needs another (deep) single outlet box.

Even if both are in one box, it would still take up as much room - it isn't like
squashing up two 13A sockets to fit a narrower box!

--

Terry

In article , lid says...

tony sayer wrote:
In article . org
, Malcolm Gray scribeth thus

at my daughter's house there is only 1 cable incoming which is then split
to provide telephone & television. So, they can't all be like that.

that is how I remember it from my friend's Cambridge Cable. One coax, a
magic box, then cable modem on one socket and a standard BT style phone
on another.

I should cross post this to cam.misc as they are all on it over there.
My memory is of a figure of eight cable that was something like coax and
cat 5.

Co-ax, RG11 IIRC and a two pair copper phone cable often referred to in
the trade as "Sidecar cable"


Right: Given that it's you Tony, I take that as authoritative.

So we have (a) God amongst us, do we? Perhaps I should bow and scrape ...

Actually, RG6 is the norm ...


So instead of using - say - baseband POTS and RF muxed on the one cable,
they run a separate pair for de dog and bone..but in the same sheath?

It's a figure-of-eight so that the cable can be split into its component parts with each
fully shrouded.

Do these help?

http://i260.photobucket.com/albums/i...G6_Siamese.jpg

http://i260.photobucket.com/albums/i...G6-Siamese.jpg

--

Terry

Terry Casey wrote:
In article , lid says...
tony sayer wrote:
In article . org
, Malcolm Gray scribeth thus

at my daughter's house there is only 1 cable incoming which is then split
to provide telephone & television. So, they can't all be like that.

that is how I remember it from my friend's Cambridge Cable. One coax, a
magic box, then cable modem on one socket and a standard BT style phone
on another.

I should cross post this to cam.misc as they are all on it over there.
My memory is of a figure of eight cable that was something like coax and
cat 5.
Co-ax, RG11 IIRC and a two pair copper phone cable often referred to in
the trade as "Sidecar cable"

Right: Given that it's you Tony, I take that as authoritative.

So we have (a) God amongst us, do we? Perhaps I should bow and scrape ...


No, but a man who does a lot of this sort of thing for a living.

Actually, RG6 is the norm ...

So instead of using - say - baseband POTS and RF muxed on the one cable,
they run a separate pair for de dog and bone..but in the same sheath?

It's a figure-of-eight so that the cable can be split into its component parts with each
fully shrouded.

Do these help?

http://i260.photobucket.com/albums/i...G6_Siamese.jpg

http://i260.photobucket.com/albums/i...G6-Siamese.jpg


They confuse me MORE actually, since my recollection is of a single coax
thingie. BUT its MANY years since I helped a friend with an installation..

Mark Carver wrote:
Bill Wright wrote:
Mark Carver wrote:

...well, morning drizzle, but here it is:-

http://www.markyboy.net/vmbox3.jpg (1 Meg)


I've sent this picture to the National Gallery of Modern Art, and told
them that you can do the actual museum installation next week. If
Damien Hirst and Tracy Emin can do it so can you. The working title of
your exhibition will be '21st Century British Workmanship'. Could you
get a few other minor exhibits together -- a few botched air cond jobs
or something?

Ah, er, how about this:- ?

http://www.markyboy.net/aircon.jpg

It that what happens when an elephant has major abdominal surgery and
the stitches fail?

Bill