CoAx - Cable vs Satellite

[jonwestuk]

Hi,

Just wired my house with Coax cables, mainly for regular digital TV. I want to future proof the house for any future Satellite or Cable connections. My query is, is the signal type used by Cable TV and Satellite TV the same as I only seem to be able to find terminals that call themselves Satellite connectors and run at the following frequencies:
Screened to EN 50083-2: >65dB to 1GHz and >55dB to 2.2GHz

I have searched around the web and cant really work out whether the cable TV frequencies within the UK fall within this banding. Wikipedia leaves me a little confused:

http://en.wikipedia.org/wiki/European_cable_television_frequencies

So can anyone on here help me. If it isn't the same I would appreciate a point to some module type connectors that work with cable tv frequencies.

Thanks ever so much,

Jon

 

[JohnW2]

Just wired my house with Coax cables, mainly for regular digital TV. I want to future proof the house for any future Satellite or Cable connections.

I would have thought that 'future proofing' would probably involve an extensive spider's web of Cat5/6 cables, which will probably be used for 'everything' before too long - I imagine that the days of coax (which is essentially 'analogue' technology) are probably very much numbered - except for the primary feeds from satellite dishes and aerials.

Kind Regards, John

 

[Taylortwocities]

Suggest this is moved to the AV forum. You may get more 'insider' knowledge there.

I've asked mods to move you.

 

[AndyPRK]

They use F type connectors.

 

[ericmark]

Coax is given a ohm rating and a leakage rating. The ohm rating for satellite is the same as terrestrial but the leakage rating for satellite is far better than terrestrial so you can use satellite cable and connectors with terrestrial but not the other way around.

The satellite ends are so easy compared with old TV ends I use satellite ends and adaptors.

 

[Sam Gangee]

Learn about cable here: http://www.glodark.com/cable.htm
and here: http://www.satcure.co.uk/tech/cable.htm

Fitting plugs: http://www.satcure.co.uk/tech/fconn.htm

 

[jonwestuk]

Thanks for all the responses. F- connectors etc I have and I have them fitted.

As I am running both the Satellite and UHF signals over the same cables (using a Loft Distro unit like this: http://www.tlc-direct.co.uk/Products/MXLDU608G.html) and am then using modular terminals that split the signal for Satellite and UHF, will the satellite signal work through the satellite connectors.

Think I just need to test it and see if it works then..

 

[JohnW2]

As I am running both the Satellite and UHF signals over the same cables ...

In that case, as eric said, you really have no choice but to use 'satellite cable'.

Kind Regards, John

 

[ericmark]

With terrestrial you have control. Size of aerial to mast head amplifier to distribution amplifier you can select.

Satellite you buy a LNB you do have some control of dish size but little else so the length of run is very important.

Once lost it's gone which is why mast head amplifiers work better than one near the TV as to if combiners and splitters have active amplifiers I don't know but I think in the main they don't it's a simple band pass filter.

I had all sorts of problems when using dish at rear of house wired through loft to TV at front but when snow moved the disk the Sky people said they could not work on it for health and safety reasons so new one fitted to front of the house. That worked A1 except again when covered in snow.

I have Sky and Free to Air and the latter will work when Sky will not. Clearly Sky boxes are a little deaf. So condemned dish rear of house works my Free to Air receiver without a problem.

So with 5 foot dish to box likely any old cable will work. With 50 foot has to be top grade.

 

[Lucid]

My query is, is the signal type used by Cable TV and Satellite TV the same as I only seem to be able to find terminals that call themselves Satellite connectors and run at the following frequencies:
Screened to EN 50083-2: >65dB to 1GHz and >55dB to 2.2GHz

I have searched around the web and cant really work out whether the cable TV frequencies within the UK fall within this banding.

You've actually asked two questions....

Are the signals the same? ANSWER: No. But in this case that doesn't really matter

Are they at different frequencies? ANSWER: Yes. Good quality TV/Satellite coax such as WF100 will handle everything from TV (DVB-T/T2) frequencies right through to satellite frequencies.


Why satellite F connectors?
It's because of the changing nature of the signals being distributed and also the increased risks of interference from both outside sources and also cables themselves acting as a transmitter. The standard Belling Lee "aerial plug" is no longer considered suitable for aerial and satellite distribution systems. This is why there's been a switch to using F connectors as used with satellite gear. They're a more direct connection since the cable itself forms the actual connection rather than the plug acting as an intermediary.

TV coax aerial plugs are still used on the backs of TVs. That's unlikely to change for the foreseeable future.

TV signals from analogue (now limited to the RF output from RF modulators in legacy products such as VCRs as well as from Sky satellite receivers) and digital (DVB-T and DVB-T2) run in frequency range from roughly 450 MHz to 850 MHz. Satellite signals for commercial TV such as Sky and Freesat occupy the range roughly between 850 MHz and 2000 MHz. [1000 MHz = 1 GHz]

The signals can co-exist in a single distribution system because the frequency ranges run concurrently rather than overlapping.


So, summing it all up, use TV coax plugs only where you have to; that's on the back of the TV or receivers only where applicable. The rest of the system including any distribution and signal amplification gear should use F connectors.

 

[jonwestuk]

So, summing it all up, use TV coax plugs only where you have to; that's on the back of the TV or receivers only where applicable. The rest of the system including any distribution and signal amplification gear should use F connectors.

That really helps me out, thanks. The real query, which maybe was not called out enough was not about the cables or the connector type. More that when running Digital TV and Satellite signals over the same cable (via my loft box) then I understand that the signal needs to be split at the end terminal using a de-combiner.

Therefore, the Module F-terminal that I have bought states that it is for satellite, but I cant find any that say that they are for cable TV. My assumption is that it will work for both, but I just wanted to check. Any thoughts?

http://www.satcure.co.uk/tech/wall_plates.htm#decombiner

 

[Sam Gangee]

I believe that Virgin Media cable TV uses frequencies in the UHF band but I've never seen them listed anywhere.

 

[Lucid]

WF125 is pretty much the same spec as VM cable. The issue with distributing VM is said to be the signal balancing re other users down the same road. Having said that, I've done jobs in homes where the VM installer has left the owner enough spare cable to add an extension to another room, so it can't be that critical.

 

[Lucid]

... when running Digital TV and Satellite signals over the same cable (via my loft box) then I understand that the signal needs to be split at the end terminal using a de-combiner.

Therefore, the Module F-terminal that I have bought states that it is for satellite, but I cant find any that say that they are for cable TV. My assumption is that it will work for both, but I just wanted to check. Any thoughts?

Ah, right. Now I understand.

It is trickier with VM. As I understand it their signal range goes from 5MHz all the way up to 860MHz. That's easy to cover with passive splitters. But I think you might run in to issues with a distribution system because of the way they chop up the frequency range on the input side using band pass filters. There are inputs for FM (87.5~108MHz), DAB (217.5~230MHz), UHF (470~854MHz A.K.A. Digital TV) and then Satellite 950MHz-2300MHz.

Then there's the issue of how Virgin's signal is going to handle the unterminated outputs at all the sockets. It just seems..... messy.

Are you likely to have a VM box each in several rooms?

 

[jonwestuk]

Thanks for the response.

Essentially I want to ensure I future proof myself to have VM in several rooms if possible. In a worst case I guess I could pass the VM signal to the loft and then split it back to each room where I want a VM box. Using the loft distro unit seemed a much better option but maybe it isnt that simple.

Think I will give it a go through the loft box and see where it takes me. You never know I may get lucky!