TV Aerial signal Find answers to popular questions or post your own regarding any aspect of home entertainment

[kelly]

Live in a village surrounded by woods and had an aerial fitted but signal strength poor. Aerial installer installed signal booster to aerial to boost terestrial signal to new freeview tv. This worked but it has affected the signal from sky box through booster to all other tv's. If I unplug aerial from sky box then sky signal to all other tv's is perfect. Is there any kind of filter i can fit or is there another way to stop terestrial signal interfering with satellite signal. Please help as local installers seem to be bereft of ideas. [/b]

[Xantech]

Hi Kelly,
new to this forum but very familiar with your problem, I do custom installations and plasma panel installs, when you unplug your aerial the reason why the picture improves on the Sky box around the house is because the normal terestrial signals are interfering with the Sky RF feed, if you look in your sky box manual it will tell you how to alter the rf channel on your digibox. Any one who wants a question answered regarding home cinema and custom installation systems please dont hessitate to contact me.
Regards
Kevin
Total Control :)

[pde]

Kevin,
If you don't mind, I'd like to take you up on your generous offer of advice; my question relates to receiving both freeview DTTV and Sky at the same time. We currently have Sky (the basic package only) because the tererstrial analogoue signal quality is notoriously poor in the area where we live and it is also a 'fringe reception area' for freeview. However, having spoken to our neighbours recently (I noticed these rather large and fancy TV areials appearing on nearby roofs pointing in the opposite direction to our standard analogue aerial), they tell me they can receive freeview via a Hi-Gain digital signal aerial. Therefore, I'm now considering doing the same and either switching over to freeview altogether or better still receiving both! Is it possible to receive both DTTV and Sky through the same setup? (i.e. a Sky dish and a Hi-Gain DTTV aerial both receiving and sending signals simultaneously to 2 or more rooms) What are the likely pitfalls to look out for when attempting to do this?
TIA rgds,
phil

[ericmark]

Channel 21 to 68 and 6 multiplexers and 4 or 5 analogue channels is causing problem your sky box needs turning to unused frequency so you need to find whats already in use on both systems. Wrote it all out then all went when I submitted so I'll try short one first this time.

[ericmark]

You need to find out what frequencies are used in your area. I live in an area where we receive signals from three transmitters each has 4 or 5 analogue and 6 multiplexers from 21 to 68 gives 49 channels of which 30 or more are used by your local broadcasters you need to tune sky to one of the 19 left. My old sky box is not tuneable and fixed to 68 which is also used by MUX3 from Winter Hill only by using a modulator can I continue to distribute sky around the house. In old days it was easy you switched on TV checked what channels are being used and pick one not being used but now you need to also have a way to check what multiplexers are using channels for freeview. Either look on internet we are not allowed to put in links or with both analogue and digital check what channels are in use.
As to high gain aerials its more to do with banding. The old analogue system kept all the channels from one transmitter close together and aerials were sold that were only able to receive with reasonable gain a small range of channels and had colour tips to show which they covered this allowed the elements to be closer together and made the aerial cheaper and lighter and less affected with by high winds but until the analogue signals are stopped the 6 freeview signals have been slotted in all over the place so a heavier longer more expensive wide band aerial is required for many transmitters although not all Winter Hill users can still use lighter banded aerials but Moel-y-parc users need the broadband aerials to work. Also there are a few local repeaters these are normally vertical where main ones are horizontal and some transmitters have odd directional transmitting Winter Hill being one until analogue is turned off there are all sorts of odd systems trying to squeeze 11 frequencies into a system designed for 4. If you have a new sky box you can change the channel but even if an old one you can buy modulators which turn any SCART signal into an analogue signal on the channel you select. Problem is your neighbors may do the same and you may mess up their signal or visa versa since each area is different you must find cure but I hope this helps you find it.

All best Eric

[Jenks_C]

Eric, could part of what you say above explain the pixelating and sound breakup on ITV. I get this in East London and also at our other place in Norfolk. I thought that the freeserve signal was a coded signal carrying all the freeview channels and was suspecting that the fault would be either at the source or within our box (both of them?).

Any ideas?

Cheers

[ericmark]

Freeview is split into 6 multiplexers. Each one contains approx one sixth of the programs available. Because these 6 signals have to be slotted into the existing network they can be all over the 21 - 68 i.e. 47 frequencies. So bad reception may have many reasons. Other transmittions on the same channel, reduced power on that channel because of interference, wrong frequency aerial and because there is a mixture of analogue and digital on the same band plan it is very hard to pin point. Video's, Sky boxes, Computer type games, Freeview boxes, etc all try to use the 47 frequencies if any of these happen to be on one that freeview use you can lose signal. And it may not be your stuff it could be something next door. And where you live you also have Europe's TV's also cutting across. Channel 5 etc. are a problem but using free to air sky dish and receiver will receive the ITV channels.

[Jenks_C]

Wow thanks Eric, a very full explanation.

[ericmark]

Sorry I may have mislead on sky. The free to air sky boxes will not pick-up Channel 5, E4, and More4 it seems they are encrypted even though they do not cost. If you get reconditioned sky box which has a card but no contract you can receive them. Something to do with copy write if they allow those on the continent to view. Seems common market is not common for TV.
I take the view no point buying freeview boxes as I will get anyway once TV is upgraded may as well get sky dish and then still of use once I upgrade about 400 channels free to view although many are shopping channels etc. Plus BBC 1 for every region same with ITV etc.