I have just been rewiring our house and have put a long length of CT100
cable (the stuff from B&Q) down from the loft to under the stairs, plus
further bits from under the stairs to where ever we might want the TV (and
the same for phone and network cabling) and was planning to join the
sections with coax plugs as required.

I was talking to a satellite system installer last week and he said you
could not have any joins in cable from a satellite dish. I really don't
want to hack off the new plaster to put in a single cable all the way down.
Is he right, or can it be joined?

Roger Moss

On Mon, 26 Apr 2004 10:27:39 +0100, "Roger Moss"
wrote:

I have just been rewiring our house and have put a long length of CT100
cable (the stuff from B&Q) down from the loft to under the stairs, plus
further bits from under the stairs to where ever we might want the TV (and
the same for phone and network cabling) and was planning to join the
sections with coax plugs as required.

I was talking to a satellite system installer last week and he said you
could not have any joins in cable from a satellite dish. I really don't
want to hack off the new plaster to put in a single cable all the way down.
Is he right, or can it be joined?

In an ideal world there'd be no joints as joints lead to signal loss.

However in practice you can join the cable. Personally, I'd recommend
fitting 'F-Plugs' to the ends of the cable to be joined. Generally
these just 'screw' onto the end of a prepared cable. However, crimp
versions are available which need a special tool.

Then use a female-to-female threaded "F" barrel to joint the two
together.

If there is an chance whatsoever of the juction getting damp wrap it
in 'Self-amalgamating' tape (Not insulation tape!)

It's quite possible all the bits are availble from B&Q or screwfix.
The bits to look out for are shown he

http://www.satcure.co.uk/accs/page7.htm

1x 090-3078 Threaded "F" barrel £0.29

2x 090-3076 Threaded "F" plug £0.16


sPoNiX

On Mon, 26 Apr 2004 10:27:39 +0100, "Roger Moss"
wrote:

I have just been rewiring our house and have put a long length of CT100
cable (the stuff from B&Q) down from the loft to under the stairs, plus
further bits from under the stairs to where ever we might want the TV (and
the same for phone and network cabling) and was planning to join the
sections with coax plugs as required.

I was talking to a satellite system installer last week and he said you
could not have any joins in cable from a satellite dish. I really don't
want to hack off the new plaster to put in a single cable all the way down.
Is he right, or can it be joined?

Roger Moss



There are two aspects to this.

- If you are thinking of adding lengths of cable on, this can be done
as long as you use proper 'F' connectors and barrels to do so and make
a decent job. Although introducing a connector, causes some effect
on the signal, if this is for the Astra constellation (carries Sky) in
the UK, then it should be fine as long as only one or two connectors
are used.

- If you are thinking that you can do something like a TV distribution
arrangement with a signal booster, no you can't do that in the same
way as you would for a TV. This is because the receiving element
at the dish - known as the Low Noise Block (LNB) is an active device
with electronics. The satellite transponders deliver signals in
horizontal and vertical polarisations and in two bands - 4
combinations in all. Depending on which channel you are watching and
hence which transponder, the LNB has to be switched by the receiver to
select it. This means a one-to-one relationship between receiver
and a conventional LNB having a single cable.

There are three ways around this.

1) Keep the one to one LNB to receiver relationship and have one
receiver. Distribute the signal out at UHF from that receiver, along
with terrestrial TV to other points in the house. This means one
receiver and one satellite program watched at a time. You could site
the receiver under the stairs because there are solutions to handle
the issue of using the remote - basically a sensor near the TV which
picks up the infra red and passes the electrical signal back along the
UHF coax.

2) You can fit a quad LNB to the dish. This is basically 4
separate LNBs in one case and has up to 4 cables coming from the dish
- each to a separate receiver. Each then runs independently.

3) You can fit a quattro LNB to the dish and run four cables to a
multiswitch (a special kind of head end) fitted (e.g.) under the
stairs. A quattro LNB provides all four signal combinations to the
multiswitch. The receivers, and you could have a lot of outlets if
you want, signal to the multiswitch as though it is a single LNB and
the multiswitch then provides the appropriate signal.
This technique is also used in multi-occupancy dwellings to avoid
needing to have lots of dishes on the roof.





..andy

To email, substitute .nospam with .gl

"Roger Moss" wrote in message
...

I was talking to a satellite system installer last week and he said you
could not have any joins in cable from a satellite dish. I really don't
want to hack off the new plaster to put in a single cable all the way
down.
Is he right, or can it be joined?

Roger Moss


He is wrong. I wonder how he thinks that people manage to have wallplates
with a satellite outlet, or even how the lead is connected to the digibox if
you're not allowed connectors! If the signal was so weak that one more
connector would kill it, there would loads of people unable to receive
anything.

Bob

"Andy Hall" wrote in message
news
There are two aspects to this.
...

Thanks! Panic over.

Does the dish have to be outdoors, or can it go in the loft (it's an old
loft, no foil insulation here!) - perhaps with a larger dish?
If outdoors, can I hide it down the garden on a long lead or is there too
much signal loss with (say) 50m cable from dish to receiver?

Roger

Roger Moss wrote:

I have just been rewiring our house and have put a long length of CT100
cable (the stuff from B&Q) down from the loft to under the stairs, plus
further bits from under the stairs to where ever we might want the TV (and
the same for phone and network cabling) and was planning to join the
sections with coax plugs as required.

I was talking to a satellite system installer last week and he said you
could not have any joins in cable from a satellite dish. I really don't
want to hack off the new plaster to put in a single cable all the way down.
Is he right, or can it be joined?


Yes, it can be. BUT there will always be a little loss and a little
reflection. Basicall older teh niners tofether, and wrap it with
isnutailin, then pull teh outher sheaths back over and connect them by
careful sodering.

Or get a connector and fit that, tape it and bury it.

Not perfection, but probably good enough.




Roger Moss

Roger Moss wrote:

"Andy Hall" wrote in message
news
There are two aspects to this.
...


Thanks! Panic over.

Does the dish have to be outdoors, or can it go in the loft (it's an old
loft, no foil insulation here!) - perhaps with a larger dish?
If outdoors, can I hide it down the garden on a long lead or is there too
much signal loss with (say) 50m cable from dish to receiver?



Satellite frequencies are severley attentuated by almost everything.
Maybe you could get away with fibreglass or persex radome in front of
it, but nothing that absorbs/contains water like tiles or slates or
timber and nothing metallic either.

Remote dishes in general need power run to them for a mast head
amplifeir of some sort to boost the signals before the long cables
reduce them all over again.


Roger

When the original SKY installer came to do mine he couldn't even be
bothered to measure the complete run of cable (straight run) and
instead joined 2 cables with f-types. That's how much they are
concerned about it.

For Sky there will no noticeable difference. If you want to pick up
weak satellite stations then it may make a difference.

What you need to consider more is the length of the cable run and to
make sure that any joins are water sealed with self amalgamating tape
or similar.

On Mon, 26 Apr 2004 10:27:39 +0100, in uk.d-i-y "Roger Moss"
strung together this:

I was talking to a satellite system installer last week and he said you
could not have any joins in cable from a satellite dish. I really don't
want to hack off the new plaster to put in a single cable all the way down.
Is he right, or can it be joined?

If you use a Global Loftbox it takes care of all the joining of cables
as the sat feed is run through the distribution amp first and also
redistributes the sat feed to other tv's throughout the house. I've
fitted a few and had good reports and also use one at home.
Or you could just join it as others have said
--

SJW
A.C.S. Ltd.

Lurch wrote:
On Mon, 26 Apr 2004 10:27:39 +0100, in uk.d-i-y "Roger Moss"
strung together this:

I was talking to a satellite system installer last week and he said you
could not have any joins in cable from a satellite dish. I really don't
want to hack off the new plaster to put in a single cable all the way down.
Is he right, or can it be joined?

If you use a Global Loftbox it takes care of all the joining of cables
as the sat feed is run through the distribution amp first and also
redistributes the sat feed to other tv's throughout the house. I've
fitted a few and had good reports and also use one at home.

It's the cable directly from the dish.
This can't go through a distribuition amp, without being decoded by the
box first, as the signals from the satellite are not normal TV ones.

On Mon, 26 Apr 2004 20:43:41 GMT, in uk.d-i-y Ian Stirling
strung together this:

It's the cable directly from the dish.
This can't go through a distribuition amp, without being decoded by the
box first, as the signals from the satellite are not normal TV ones.

Try reading up on the product I mentioned in the post. I won't point
out the several incorrect comments in your post just yet, nah **** it,
I will.
I know it's the cable directly from the dish, no need to point that
out again.
The satellite signal can go through a distribution amp, just not a
normal uhf\vhf amp.
It's a signal in a frequency range, it can be amplified by a suitably
matched amp. It doesn't need decoding before being amplified.
I know satellite signals are different from normal tv ones,
If I got it wrong how do you suppose it all worked when it was
installed and tested? Bearing in mind I have fitted these units, you
obviously haven't.
--

SJW
A.C.S. Ltd.

Lurch wrote:
On Mon, 26 Apr 2004 20:43:41 GMT, in uk.d-i-y Ian Stirling
strung together this:

It's the cable directly from the dish.
This can't go through a distribuition amp, without being decoded by
the box first, as the signals from the satellite are not normal TV
ones.

Try reading up on the product I mentioned in the post. I won't point
out the several incorrect comments in your post just yet, nah **** it,
I will.
I know it's the cable directly from the dish, no need to point that
out again.
The satellite signal can go through a distribution amp, just not a
normal uhf\vhf amp.
It's a signal in a frequency range, it can be amplified by a suitably
matched amp. It doesn't need decoding before being amplified.
I know satellite signals are different from normal tv ones,
If I got it wrong how do you suppose it all worked when it was
installed and tested? Bearing in mind I have fitted these units, you
obviously haven't.

I've got a question on the Loftbox Lurch, I've one installed and working
fine with 'normal' TV and Sky at my sister's and another sat here on the
floor next to me waiting to be fitted here. Just what the heck are Gold Mine
points and what can I do with 10 of them???

--
James...
www.jameshart.co.uk

On Mon, 26 Apr 2004 21:41:30 GMT, (Lurch)
wrote:

On Mon, 26 Apr 2004 20:43:41 GMT, in uk.d-i-y Ian Stirling
strung together this:

It's the cable directly from the dish.
This can't go through a distribuition amp, without being decoded by the
box first, as the signals from the satellite are not normal TV ones.

Try reading up on the product I mentioned in the post. I won't point
out the several incorrect comments in your post just yet, nah **** it,
I will.
I know it's the cable directly from the dish, no need to point that
out again.
The satellite signal can go through a distribution amp, just not a
normal uhf\vhf amp.
It's a signal in a frequency range, it can be amplified by a suitably
matched amp. It doesn't need decoding before being amplified.
I know satellite signals are different from normal tv ones,
If I got it wrong how do you suppose it all worked when it was
installed and tested? Bearing in mind I have fitted these units, you
obviously haven't.

I've looked at this one, Lurch, and from the diagram it appears to
work as follows:

- TV, VHF and satellite dish cables are brought together at the
Loftbox and combined though a filter. THere may or may not be
amplification. VHF signals are those below 300MHz, then UHF
terrestrial TV goes from approx 400 to approx 850MHz. The
satellite IF signal between the LNB and the receiver ranges from about
950 to 1950 MHz. The main point here is that it is a cabling
convenience of everything from the box to the prime TV position on one
cable.

- A single cable goes from the Loftbox to a filter box (typically in
the living room) which then splits the signals back out again into TV,
VHF and satellite.

- The TV and satellite signals go to the (typically Sky) satellite
receiver.

- One UHF output from the satellite box goes to the living room TV,
the other optionally back to the Loftbox on a separate cable.

- VHF and UHF distribution amplification in the Loftbox then provides
for outlets to go to a number of TV sets (4?) in other parts of the
house.

- If all of this is connected up, it should be possible to watch
terrestrial TV and the satellite channel selected on the satellite
box. With TVLink sensors, the satellite box could also be controlled
from the other rooms with TV.

However........

What I am pretty sure that it won't do is to deliver a satellite
signal to more than one receiver in one place.

This requires either a quad LNB or a quattro LNB with multiswitch.
Both of those require four cables (actually up to 4 with a quad) from
the LNB.
..andy

To email, substitute .nospam with .gl

On Mon, 26 Apr 2004 23:20:00 +0100, in uk.d-i-y "James Hart"
strung together this:

Just what the heck are Gold Mine
points and what can I do with 10 of them???

Good question, obviously a new thing they've started then!
--

SJW
A.C.S. Ltd.

On Mon, 26 Apr 2004 23:31:54 +0100, in uk.d-i-y Andy Hall
strung together this:

I've looked at this one, Lurch, and from the diagram it appears to
work as follows:

- TV, VHF and satellite dish cables are brought together at the
Loftbox and combined though a filter. THere may or may not be
amplification. VHF signals are those below 300MHz, then UHF
terrestrial TV goes from approx 400 to approx 850MHz. The
satellite IF signal between the LNB and the receiver ranges from about
950 to 1950 MHz.

Sounds about right.

The main point here is that it is a cabling
convenience of everything from the box to the prime TV position on one
cable.

Or two, if you use the return feed as well.

- A single cable goes from the Loftbox to a filter box (typically in
the living room) which then splits the signals back out again into TV,
VHF and satellite.

- The TV and satellite signals go to the (typically Sky) satellite
receiver.

- One UHF output from the satellite box goes to the living room TV,
the other optionally back to the Loftbox on a separate cable.

- VHF and UHF distribution amplification in the Loftbox then provides
for outlets to go to a number of TV sets (4?) in other parts of the
house.

Yep, you can get 8 way as well, and they also do a cascadable amp to
add more if required.

- If all of this is connected up, it should be possible to watch
terrestrial TV and the satellite channel selected on the satellite
box. With TVLink sensors, the satellite box could also be controlled
from the other rooms with TV.

Yep.

However........

What I am pretty sure that it won't do is to deliver a satellite
signal to more than one receiver in one place.

No more than a single LNB would under any 'normal' circumstances.

This requires either a quad LNB or a quattro LNB with multiswitch.
Both of those require four cables (actually up to 4 with a quad) from
the LNB.

Yep, but then you'd need to bypass the loftbox therefore rendering it
as just a UHF distribution amp. Unless you combine the four signals
from the quad before the loftbox and back out again somewhere,
although by the time you've finished you might want to just design a
system from scratch without the loft box but use your own
splitters\filters etc.
--

SJW
A.C.S. Ltd.

On Mon, 26 Apr 2004 23:12:45 GMT, (Lurch)
wrote:


Yep.

However........

What I am pretty sure that it won't do is to deliver a satellite
signal to more than one receiver in one place.

No more than a single LNB would under any 'normal' circumstances.

Right. The point that I was trying to get to so that people would not
be confused is that a simple distribution amp can't take a single LNB
signal and deliver it to N positions for simultaneous use of
receivers. The Loftbox picture almost gives that impression, but
obviously it's not technically possible.



This requires either a quad LNB or a quattro LNB with multiswitch.
Both of those require four cables (actually up to 4 with a quad) from
the LNB.

Yep, but then you'd need to bypass the loftbox therefore rendering it
as just a UHF distribution amp. Unless you combine the four signals
from the quad before the loftbox and back out again somewhere,
although by the time you've finished you might want to just design a
system from scratch without the loft box but use your own
splitters\filters etc.

This is basically what I did.

I wanted to have a fairly large number of outlets around the house for
TVs and VHF radio simply so that rooms can be rearranged without long
trailing leads. The shape of the house lends itself much more to
having a tree shaped cabling arrangement, so I created a headend for
UHF and VHF distribution in the loft. Cabling is run from there to
passive splitters at various locations and then sockets are cabled to
these. This head end has signal equalising filters etc. to give
equal results on all channels from two transmitters. There will be
between 20 and 30 outlets when it's finished.

I then wanted satellite distribution to a smaller number of outlets
where satellite receivers may be located. These have to be home run
cabled to a multiswitch in the loft.

For this, I have used a Spaun cascadeable multiswitch to provide for
inputs from two quattro satellite LNBs (one Astra, one Hotbird) and up
to 10 outlets.

http://www.spaun.de/html/sms_9941_nf.html

http://www.spaun.de/html/smk_9961_f.html

A DVB satellite receiver is able to select the LNB as well as the
polarisation/band through signals up the cable.

This switch can also take an input from the UHF/VHF headend, so I can
use a triplexing filter at the outlet, rather like the Loftbox does
and avoid a separate cable from the trunked system.



..andy

To email, substitute .nospam with .gl