Extending and/or splitting coax cable - what's the correct way?

[JoeJoe]

Just added another TV to the collection...

I want to be able to split it between two TV's , but having moved the
old TV around, the cable now doesn't reach either of the TVs.

I am looking for two possible solutions:

1. Assuming that no amplification is required (I'll have to verify
this): use a 1-to-2 junction box (or similar) to split the cable under
the house and run cables to both TV.

2. If the signal needs boosting: extend the cable to a point where I can
fit a booster/splitter.

Whilst the space under the house offers protection from direct sun light
and/or rain, it is almost the same as leaving the cable/connectors
outside (very windy/cold, etc).

I would be most grateful for advice as to the correct way to
split/extent the cable is what is essentially our outdoor conditions.
Links to exact part will also be great.

Many thanks.

[fred]

In article <0K-dnb8awb5CH4jS...@brightview.co.uk>, JoeJoe
<n...@mail.com> writes

Plugs (F-type) (10pk):
http://www.screwfix.com/p/arse/17061

Barrel jointer (10pk):
http://www.screwfix.com/p/arse/95730

Splitter:
http://www.screwfix.com/p/arse/99105

Connector fitting instructions:
http://satcure.co.uk/tech/fconn.htm

Ignore the silicon grease and taping mentions for non-outdoor use.

The plugs are basically strip, fold back braid and twist on, sounds
rough but they are secure if sized correctly. Just buy some and try it,
post back if you have trouble, the connection should survive quite a tug
if made correctly. The coax (solid) core forms the connector pin.

Suck it and see as is and post back if you think you need a booster.
--
fred
it's a ba-na-na . . . .

[Paul D Smith]

"JoeJoe" <n...@mail.com> wrote in message
news:0K-dnb8awb5CH4jS...@brightview.co.uk...

Ask at uk.rec.digital-tv if you get no responses here or want more details
than this.

Sounds like you need a passive TV splitter - most seem to go for those
either connecting directly to the cable or using F-connectors instead of the
Belling plugs (the type that plugs into the TV). They have components
inside to stop reflections etc and are NOT the same as splicing the cables
in a simple Y (despite what many cowboys seem to think). TV cable is also
supposed to be weather proof so no issues there.

Also, if you need a boost, boost as close to the aerial as possible
otherwise you're also boosting any noise which has crept in along the cable.

Paul DS.

[The Natural Philosopher]

A way that works to extend cables without TOO much impedance change is
to strip them back and get the outer sheaths out of the way and lap
solder the smallest amount of the inners you can get away with together
and, if you are careful, push the insulation over that joint so the
dielectric is more or less continuous, then tape that up with a bit of
PVC tape and connect the outers in some way. Brass shim or tinplate cut
from a mustard tin wrapped round the cable (or tube slid over it) will
preserve the outer continuity and geometry. Solder the braids to that.

Then wrap the lot in self amalgamating tape.

Its probably no worse than a custom connector, electrically, and is more
proof against environmentally induced deterioration.

[Dave Plowman (News)]

In article <0K-dnb8awb5CH4jS...@brightview.co.uk>,

JoeJoe <n...@mail.com> wrote:
> I would be most grateful for advice as to the correct way to
> split/extent the cable is what is essentially our outdoor conditions.
> Links to exact part will also be great.

There are outdoor splitters available.

--
*A person who smiles in the face of adversity probably has a scapegoat *

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

[Graham.]

Thanks, but I'll continue to use two plugs and a barrel if you don't
mind.

--
Graham.
%Profound_observation%

[hugh]

In message <in2bh7d0g4dd0bj86...@4ax.com>, Graham.
<m...@privacy.net> writes

Use a male/female connection - that cuts out one joint.
--
hugh

[The Natural Philosopher]

As I said. the above is probably better electrically, costs less and is
less liable to corrosion.

But no one is forcing you to do it.

Or to crimp mains cables instead of using junction boxes.

[Peter Crosland]

"fred" <n...@for.mail> wrote in message news:OQgjoQC2fYFPFwPL@y.z...

Generally good advice except for sealing. The best way of making the joints
weatherproof is to use self amalgamating tape. Properly applied it will last
for at least twenty years. You can get the tape from Screwfix product code
87717.

Peter Crosland

[JoeJoe]

Thanks a lot for that - just the answer I was hoping for as I already
have the f-type fittings from another job...

Just out of interest - what does "power pass to all ports" mean?

Also, is there any interference issue with running the coax cable
alongside CAT5e cables? I am only talking about 2m or so.

[Bill Wright]

JoeJoe wrote:

> Whilst the space under the house offers protection from direct sun light
> and/or rain, it is almost the same as leaving the cable/connectors
> outside (very windy/cold, etc).

Buy a plastic box from CPC and put the amp in that. That's what we do.

Bill

[Bill Wright]

Graham. wrote:

>> A way that works to extend cables without TOO much impedance change is
>> to strip them back and get the outer sheaths out of the way and lap
>> solder the smallest amount of the inners you can get away with together
>> and, if you are careful, push the insulation over that joint so the
>> dielectric is more or less continuous, then tape that up with a bit of
>> PVC tape and connect the outers in some way. Brass shim or tinplate cut
>>from a mustard tin wrapped round the cable (or tube slid over it) will
>> preserve the outer continuity and geometry. Solder the braids to that.
>>
>> Then wrap the lot in self amalgamating tape.
>>
>> Its probably no worse than a custom connector, electrically, and is more
>> proof against environmentally induced deterioration.
>>
>
> Thanks, but I'll continue to use two plugs and a barrel if you don't
> mind.
>

But look at this:

http://dl.dropbox.com/u/11023364/JOINT1%20v8..jpg

Bill

[John Rumm]

On 17/01/2012 16:54, JoeJoe wrote:

> Thanks a lot for that - just the answer I was hoping for as I already
> have the f-type fittings from another job...
>
> Just out of interest - what does "power pass to all ports" mean?

Masthead aerial amplifiers etc require power to operate. Usually the
power supply for these is kept in the house, and the power is fed up the
co-ax to the masthead amp. Hence if you have something like this being
powered from the co-ax, anything you place in the co-ax along the way
must also pass the power through. Some splitters only do so on one
particular port - hence in those cases you need to take care to put the
outgoing lead with the PSU on it, on the right socket of the splitter.

Ones with power pass on all ports does not have this restriction.

> Also, is there any interference issue with running the coax cable
> alongside CAT5e cables? I am only talking about 2m or so.

Not usually any problem.


--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

[fred]

In article <z5OdnRidULGpP4jS...@brightview.co.uk>, Peter
Crosland <g6...@yahoo.co.uk> writes

Read again . . . .

[Graham.]

On Tue, 17 Jan 2012 17:12:08 +0000, Bill Wright <bi...@invalid.com>
wrote:

There is no scale reference in that diagram. I was wondering if that
is how they join high power RF transmission lines the size of tree
trunks.

--
Graham.
%Profound_observation%

[Graham.]

>>Thanks, but I'll continue to use two plugs and a barrel if you don't
>>mind.
>>
>Use a male/female connection - that cuts out one joint.

Do you mean the Belling-Lee ones?

I have never liked the female ones because the inner only goes in
about 3mm and can easily shrink back that amount. Soldering them is
not practical.

--
Graham.
%Profound_observation%

[Bill Wright]

John Rumm wrote:
> On 17/01/2012 16:54, JoeJoe wrote:
>
>> Thanks a lot for that - just the answer I was hoping for as I already
>> have the f-type fittings from another job...
>>
>> Just out of interest - what does "power pass to all ports" mean?
>
> Masthead aerial amplifiers etc require power to operate. Usually the
> power supply for these is kept in the house, and the power is fed up the
> co-ax to the masthead amp. Hence if you have something like this being
> powered from the co-ax, anything you place in the co-ax along the way
> must also pass the power through. Some splitters only do so on one
> particular port - hence in those cases you need to take care to put the
> outgoing lead with the PSU on it, on the right socket of the splitter.
>
> Ones with power pass on all ports does not have this restriction.

But may incorporate diodes so DC doesn't pass from port to port. But
that stops you using the splitter 'backwards' with LP.

Bill

[Bill Wright]

Horrid things. Use a plug and a line conn.

Bill

[tony sayer]

In article <qohbh7thaj98npjkc...@4ax.com>, Graham.
<m...@privacy.net> scribeth thus

No they use connectors, large ones, and there're bolted together!...

>

--
Tony Sayer

[JoeJoe]

On 17/01/2012 17:12, John Rumm wrote:
> On 17/01/2012 16:54, JoeJoe wrote:
>
>> Thanks a lot for that - just the answer I was hoping for as I already
>> have the f-type fittings from another job...
>>
>> Just out of interest - what does "power pass to all ports" mean?
>
> Masthead aerial amplifiers etc require power to operate. Usually the
> power supply for these is kept in the house, and the power is fed up the
> co-ax to the masthead amp. Hence if you have something like this being
> powered from the co-ax, anything you place in the co-ax along the way
> must also pass the power through. Some splitters only do so on one
> particular port - hence in those cases you need to take care to put the
> outgoing lead with the PSU on it, on the right socket of the splitter.
>
> Ones with power pass on all ports does not have this restriction.
>
>> Also, is there any interference issue with running the coax cable
>> alongside CAT5e cables? I am only talking about 2m or so.
>
> Not usually any problem.
>

Thanks again.

[John Rumm]

Funny you should say that, but I wondered to myself if they various
ports are isolated from each other as I typed that ;-)

[The Natural Philosopher]

It works at any scale it is practical to make the joint.

[fred]

In article <htGdnbKhff2gQIjS...@brightview.co.uk>, John
Rumm <see.my.s...@nowhere.null> writes

>On 17/01/2012 19:18, Bill Wright wrote:
>> John Rumm wrote:
>>> On 17/01/2012 16:54, JoeJoe wrote:
>>>
>>>> Thanks a lot for that - just the answer I was hoping for as I already
>>>> have the f-type fittings from another job...
>>>>
>>>> Just out of interest - what does "power pass to all ports" mean?
>>>
>>> Masthead aerial amplifiers etc require power to operate. Usually the
>>> power supply for these is kept in the house, and the power is fed up
>>> the co-ax to the masthead amp. Hence if you have something like this
>>> being powered from the co-ax, anything you place in the co-ax along
>>> the way must also pass the power through. Some splitters only do so on
>>> one particular port - hence in those cases you need to take care to
>>> put the outgoing lead with the PSU on it, on the right socket of the
>>> splitter.
>>>
>>> Ones with power pass on all ports does not have this restriction.
>>
>> But may incorporate diodes so DC doesn't pass from port to port. But
>> that stops you using the splitter 'backwards' with LP.
>
>Funny you should say that, but I wondered to myself if they various
>ports are isolated from each other as I typed that ;-)
>

Snap!

Screwfix used to do the single power port version (Labgear WBS2F) at
silly cheap prices so I got my few examples there. Current offering
appears to be Labgear FBS402, note the directional power feed arrows on
case pic suggesting diodes as per Bill's post (Ta).

For comedy effect it appears that the current version of WBS2F has the
power port on the right whereas mine have it on the left. Nothing like
continuity of design eh?

[Bill Wright]

fred wrote:

> Screwfix used to do the single power port version (Labgear WBS2F) at
> silly cheap prices so I got my few examples there. Current offering
> appears to be Labgear FBS402, note the directional power feed arrows on
> case pic suggesting diodes as per Bill's post (Ta).
>
> For comedy effect it appears that the current version of WBS2F has the
> power port on the right whereas mine have it on the left. Nothing like
> continuity of design eh?

A while back we needed some that would pass 24VDC from one port to the
'input' and the other port. It was easy to short out the diodes. This
was with some CPC ones designed for satellite IF.

Bill

[JoeJoe]

On 17/01/2012 14:38, fred wrote:

Spent an hour under the house today and connected everything:

Cable from aerial (on roof) to splitter - around 15-20m - as before
adding the splitter.
- SF didn't have the one you suggested, so I bought this one instead -
http://www.screwfix.com/p/labgear-professional-splitter-6-way/48074.
- Connected TV that was originally connected to the aerial cable to
splitter - signal dropped from 100% to 99%.
- Connected second TV to splitter - cable around 10-15m. Signal only
9%... :-(. Amazingly all the channels seem to work OK, including the TV
guide. Only BBC channels are pixelated and unwatchable (and show 7%).

Any idea how to improve before I go down the amplification route?

PS: Used F-type plugs, wall plates, and good quality cable, so don't
think there is a problem there?

[thirty-six]

On Jan 21, 9:06 pm, JoeJoe <n...@mail.com> wrote:
> On 17/01/2012 14:38, fred wrote:
>
>
>
>
>
>
>
>
>

> > In article <0K-dnb8awb5CH4jSnZ2dnUVZ8oUAA...@brightview.co.uk>, JoeJoe

> - SF didn't have the one you suggested, so I bought this one instead -http://www.screwfix.com/p/labgear-professional-splitter-6-way/48074.

> - Connected TV that was originally connected to the aerial cable to
> splitter - signal dropped from 100% to 99%.
> - Connected second TV to splitter - cable around 10-15m. Signal only
> 9%... :-(. Amazingly all the channels seem to work OK, including the TV
> guide. Only BBC channels are pixelated and unwatchable (and show 7%).
>
> Any idea how to improve before I go down the amplification route?

If it's only a specific channel, it's reception strength may be
improved with variation within the wavelength in the aerial height
It's a variation of possibly a foot. Just alter the height to
maximise the low powered channel.

[Bill Wright]

thirty-six wrote:

>> Any idea how to improve before I go down the amplification route?
>
> If it's only a specific channel, it's reception strength may be
> improved with variation within the wavelength in the aerial height
> It's a variation of possibly a foot. Just alter the height to
> maximise the low powered channel.

No, that sort of pratting about is a waste of time. Signal levels are
generally too low. But a one input one output mains powered amp, gain
around 12dB, fit it on the aerial feed, as close to the aerial as
possible, but right next to the splitter if that's the best you can do.

Blake Proception PROAMP 11 is ideal.
http://www.blake-uk.com/proamp.aspx

Better still, if you can get to the aerial fit a 16dB masthead amp.
Proception, Vision, Labgear, Antiference.

Bill

[JoeJoe]

Very difficult to reach the aerial - 15m high on gable end on a hill side...

It is also going to be difficult to provide power near the bottom of the
aerial.

Is there any point in amplifying the signal just before the cable is
connected to the far-away TV?

[Bill Wright]

JoeJoe wrote:

> It is also going to be difficult to provide power near the bottom of the
> aerial.
>
> Is there any point in amplifying the signal just before the cable is
> connected to the far-away TV?

Not really. A marginal improvement might, at best, be obtained. It
certainly doesn't address the problem. If you can get power to the
splitter position put the mains powered amp just before the splitter.

If not, use a masthead amp with a separate mains power unit. The 12V DC
goes up the coax. The problem is that the amp still needs to be before
the splitter (this is vital), but the splitter might not pass the DC
power. Does the splitter have 'DC pass' written on it,

http://cpc.farnell.com/labgear/fbs138/splitter-8-way-power-pass/dp/AP02113
http://cpc.farnell.com/unbranded/fbs138/f-type-splitter-8-way/dp/AP00308

You could actually use a non DC splitter and bypass it for DC by the use
of two of these:
http://cpc.farnell.com/unbranded/a1330/line-power-inserter/dp/SE00411
but it's rather a faff.

Alternatively

http://cpc.farnell.com/labgear/pum141-psm114/10db-masthead-amplifier-kit/dp/AP01495
http://cpc.farnell.com/labgear/pum141/amplifier-masthead-4way/dp/AP01340

followed by a few two-way splitters on the non-powered legs to give
enough outputs (split the shortest feeds).

Bill

[thirty-six]

Not usually, but might be worth a go if you have low noise levels.

[fred]

In article <FvCdnYpKH6VrtYbS...@brightview.co.uk>, JoeJoe
<n...@mail.com> writes

>
>Spent an hour under the house today and connected everything:
>
>Cable from aerial (on roof) to splitter - around 15-20m - as before
>adding the splitter.
>- SF didn't have the one you suggested, so I bought this one instead -
>http://www.screwfix.com/p/labgear-professional-splitter-6-way/48074.

Ah, problem is that the incoming signal power is split by the number of
ways on the splitter, irrespective of the number of loads connected.
Thus a 6 way splitter will reduce signal power to 17% vs the 50% avail
on the proposed 2W splitter.

>- Connected TV that was originally connected to the aerial cable to
>splitter - signal dropped from 100% to 99%.

That sounds ok.

>- Connected second TV to splitter - cable around 10-15m. Signal only
>9%... :-(. Amazingly all the channels seem to work OK, including the TV
>guide. Only BBC channels are pixelated and unwatchable (and show 7%).
>

Something is wrong here, 15m of cable is not that great a loss so I
wouldn't expect it to go over the edge from 99% to duff with just that.
Check for stray hairs of braid that might be shorting the signal (no it
doesn't always result in no signal).

>Any idea how to improve before I go down the amplification route?
>

If you don't need all those ways off the splitter then find a 2W
splitter of the same quality (F-conns, soldered cab construction eg.
Labgear) as the signal will be 3 times stronger from that alone

If you need lots of splits then you will need a distribution amp.

>PS: Used F-type plugs, wall plates, and good quality cable, so don't
>think there is a problem there?
>

If you have spare cable, make up a long fly lead to temporarily replace
your long installed section to see if it works ok. Was it really good
cable (copper foil and braid screening)? No kinks in the cable (easily
done in a back box)?

If you find you need an amp (after trying the 2W splitter alone and a
replacement cable) then those suggested by Bill will be good as this is
his expert topic.