Distributing satellite TV around the house

A thought occurs to me regarding the method I'm currently employing to receive SKY TV in the bedrooms.

At the moment I have the downlead from the aeriel going to the Sattelite receiver, then back up to a TV booster which distributes the combined signals around the home.

However, as TVs are going digital and not employing the use of analogue signals any more, will I still be able to use this method ?

Just a thought!

Reply to
Simon (Dark Angel)
Loading thread data ...

You misunderstand! Transmitters are going digital! Unless you choose to alter the way your signal is distributed - nothing will change.

Reply to
Roger

the digital terrestrial signals are on similar frequencies to the analogue ones, so any distribution that works for analogue terrestrial should work for digital terrestrial. About the satellite stuff, I simply haven't a clue.

Reply to
The Natural Philosopher

That distribution will still work but you will need DTTV sets or set top boxes for each analogue TV.

Reply to
Dave Liquorice

I'm not sure whether the OP is asking the opposite question - ie: distribution from the satellite receiver is analogue around the house, but will analogue input still be supported by any new TVs in the future?

This is a question that I was going to be looking at soon, as I want a small flat TV to replace an old CRT one, but need it to receive analogue signals from a number of devices.

This would also be a question for those distributing signals from a PC using a TV-OUT option.

SteveW

Reply to
Steve Walker

method ?

Could be read that way I guess. I should imagine all current "digital" TVs will also have analogue tuners in them. What will happen post 2012 is anybodies guess.

Reply to
Dave Liquorice

That was the point I was indeed making, sorry for not being clearer.

Yes, it suddenly occured to me that future TV sets, in all likelihood, won't support analogue reception, so how would one go about receiving signals from the RF out on ones receiver?

Reply to
Simon (Dark Angel)

The simple answer is that you wouldn't be able to. You *could* distribute to such a TV by using video rather than RF as, digital tuner only or not, you will still almost certainly have analogue scart inputs. It would be a 'messy' solution though, involving three screened cables - one for video, and two for sound. However, I think it is moderately unlikely that analogue tuner inputs on TVs, are going to disappear anytime soon. There are still many areas of the world that use analogue transmissions, and are likely to for some years yet. The TV manufacturers probably won't waste production on lots of different territory-specific models, but will continue to produce 'universal' ones that have both analogue and digital tuners.

As to whether an existing analogue distribution system will handle terrestrial digital signals, that is actually not a given. Although the frequencies involved are, as someone else commented, in the same band as the existing transmissions, the various multiplexes that you can receive are scattered from one end of that band to the other. Various non linearities in the gain / bandwidth characteristics of any distribution amplifiers involved, along with varying cable losses across the band, can result in some multiplexes falling below acceptable quality at some points on the network. Also, any existing distribution amplifiers involved, may well be channelised to suit the 'group' that the original analogue signals fell in - particularly if the distribution system was professionally installed, rather than a DIY job using broadband components from Maplin or wherever.

I have a trunked distribution system in my house, that I put in some years ago. It uses quality twin screen cable, and professional amplifiers and tapper units. The analogue signals are nothing short of perfect at every drop. The digital signals, however, are extremely variable at various points. The situation was improved by replacing my existing group 'A' aerial with a broadband type, but even so, when the analogue transmissions in my area cease, I will probably have to give the system a major rework, with new amplifiers etc, to achieve the same level of 'goodness' of signal at each drop.

Even low quality wall sockets, can have a profound effect on digital signals, that wasn't apparent on analogue ones. Don't believe all the hype about how 'perfect' digital terrestrial signals are. They are actually a lot less forgiving than you might think. It doesn't take an awful lot to upset them, particularly whilst the power levels of the transmitters carrying them, are still low ...

Reply to
Arfa Daily

Well your experience is 100% opposite to mine. Digital terrestrial through a distribution amp is perfectly as good as the analogue was.

If you have a decent amp, cable and socket quality is almost irrelevant. If you have wired them up correctly of course,

But then perhaps I know what I am doing ;-)

Reply to
The Natural Philosopher

Simon (Dark Angel) formulated the question :

Of course, it will continue to work, but only until you replace each TV with digital only sets. I'm not aware of any sets sold or on sale which are digital only, but no doubt once analogue is turned off everywhere - the will start to sell them.

What you would do then, I do not know.

Reply to
Harry Bloomfield

at which point one assumes that satellite boxes will start to feed MUXED digital signals.

Arguably a better solution anyway.

Reply to
The Natural Philosopher

It happens that Arfa Daily formulated :

That is not my experience. We had an old antenna, feeding down via old type 75ohm, to a distribution amp, then old 75ohm out to each room. In a good to strong signal area, where the narrow band antenna was supposedly just about adequate.

Only one TV set suffered badly on both analogue and digital, the one in the kitchen. It's feed cable was replaced a couple of times over the years, but despite cable, distribution outlet and TV swaps it always remained poor on both digi and analogue - this is the second to shortest cable run.

Other TV's on the system suffered the odd glitch in reception - A couple of years ago I fitted a new larger wideband antenna and replaced most of the feeds with the modern double fully screened cable described as sat cable, then most of the problems finally went away. All the feeds are run indoors, apart from a very short section leading out from the loft to the antenna on the chimney. The kitchen reception improved most of all, but it remains not quite as good as the rest.

I'm still using mostly Belling Lee plugs and sockets, but intend to eventually swap everything over to F plugs when I get a roundtuit. I ran some experiments, between the two and found this made not much difference - hence the roundtuit.

Reply to
Harry Bloomfield

The Natural Philosopher submitted this idea :

Agreed, but I have yet to come across an RF in to MUXED add on converter.

Reply to
Harry Bloomfield

Ah. I see. My almost 40 years in the trade says I don't then ... Fair enough. Do you know what a trunked distribution system is ?

Whether or not an existing system works (well) or not depends on many things, including the antenna installation, any masthead preamps involved, any combiners or diplexers involved, the quality of the cable used for the drops to the various rooms, and that of the trunk cable if it happens to be that sort of system, the age and quality of the distribution or trunk driver amplifier, the quality of the wall sockets, the quality of the tappers on a trunked system, and of course, how good the digital signal is in the first place - both strength and quality, of course.

Most analogue distribution systems did not need to broadband. Digital ones do.

But then I guess you know all that ... d;~}

Arfa

Reply to
Arfa Daily

Thanks for the replies all, guess its a case of wait and see then!

Reply to
Simon (Dark Angel)

Most distribution amplifiers are 'DC to light' anyway.

If you have installed a bunch of tuned stuff anywhere than at the masthead then all that does is prove my point: You don't really understand what you are doing.

If you have not used correct buffered outputs that do not transfer faults in one cable to another, it proves my point, you don't know what you are doing.

If you cant correctly terminate a cable to a socket so you get reflections and frequency dependent attenuation, it proves my point, you don't know what you are doing.

The ONLY difference digital makes is that it uses a somewhat higher bandwidth ..the only place that SHOULD be releavant is in any tuned elements.

The only place ther SHOULD be tuned elements, is the aerial itself, and if it has one, a masthead amp. Possibly.

There should be NO tuned elements in the distribution system, if its been installed by someone who knows what they are doing, as opposed to simply having repeated the same mistakes for 40 years.

I've met plenty of mechanics '40 years in the trade' who still cant diagnose an injection fault.

Reply to
The Natural Philosopher

If I could come in late and ask a very basic question: I don't understand much of this thread, but is the conclusion that at some point in the medium-term but foreseeable future that co-axial distribution systems will be no good and new cables will need to be installed? I currently have a LOT of co-ax and cat 5e festooned around the house. If the co-ax becomes no good for the telly due to digitisation will the cat 5 be any use?

Reply to
Martin Pentreath

Martin Pentreath pretended :

The old type (generally brown) coax, with poor screening really needs to be replaced with the much better quality couble screened coax (which is generally black). This should have an outer, followed by a thin copper overlapped tape, then a woven screen. Signal loss is less and it is less susceptible to interferrance.

Reply to
Harry Bloomfield

I expect that future TVs will retain the analogue tuner capability, for just such reasons. It may be that some cost reduced sets don't, however they will no doubt accept base band video via scart etc, so that would open the market for small standalone "demodulators" in the same way as one can now by modulators.

Reply to
John Rumm

You may find that it works perfectly. Remember you are not comparing like with like at the moment. The digital system is operating at much reduced power until after DSO. Another 9dBuV in the headend may make all the difference.

Indeed - that is the crux. Once the power level is up many of the problems should go. There will be differences. Some problems are handled better by one system or the other as you would expect.

Reply to
John Rumm

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.