Aerial location

[Lord Flashheart]

I have very annoying pixelating of my TV screen which isn't constant but every few minutes. When it does it the sound goes too. When there's no pixelating, the picture is perfect, as is the sound. I'm guessing this is an aerial/coaxial issue as it seems to be all channels.
Currently my aerial is on the roof and gets hit by strong north easterly winds as it's very exposed. Whether this moves the coax and aerial about, I'm not sure. So I'm thinking of having the aerial fitted in the loft and running a new coax to the TV indoors.
Can anyone give some advice about setting up in a loft? i.e do I need a booster, specific aerial, etc? I'll probably get someone in to do the job as I just don't have the time, so being armed with some info could be useful.

[greygoose]

When we moved into our new house it had two aerials, pointing at different transmitters and a booster thing to switch between the two depending on which was strongest, maybe ask the aerial bloke if he can direct your new aerial at another transmitter?

[Mr Pointy]

If the aerial & the cable connections are in good condition it shouldn't be much of an issue being outside but over time they can get corroded if the installer didn't waterprooof the joint box. You may find that a new aerial & downlead will sort the issue & it's an easy first step.

Whether you can fit an internal aerial depends on how far you are from the mast & the transmitter power. It may be a bigger aerial can overcome the signal loss through the roof to give a decent signal & a good local installer should know the likelihood of success. This site has a lot of information:
https://www.aerialsandtv.com/knowledge

There's transmitter information here - look at the Freeview section in the sidebar:
https://ukfree.tv/section/News_headlines

[Lucid_AV]

Lord Flashheart said:

I have very annoying pixelating of my TV screen which isn't constant but every few minutes. When it does it the sound goes too. When there's no pixelating, the picture is perfect, as is the sound. I'm guessing this is an aerial/coaxial issue as it seems to be all channels.
Currently my aerial is on the roof and gets hit by strong north easterly winds as it's very exposed. Whether this moves the coax and aerial about, I'm not sure. So I'm thinking of having the aerial fitted in the loft and running a new coax to the TV indoors.
Can anyone give some advice about setting up in a loft? i.e do I need a booster, specific aerial, etc? I'll probably get someone in to do the job as I just don't have the time, so being armed with some info could be useful.

The transmissions for digital TV have changed quite a bit in the last 10 years. First, it was the 800MHz clearance which saw transmissions rejigged to move out of channels 61 to 69, and more recently work has been completed on the 700MHz clearance to move transmissions out of the ch50-ch60 range.

Before these changes we also had the transition from analogue to digital. Depending on the age of your aerial, what it was installed for (a Group aerial or a wideband aerial that's no longer a good match for your local transmissions), it's alignment (not all aerials point in the same direction even though they receive from the same transmitter), whether it was amplified to cope with weak early DVB-T transmissions, the presence of trees and other obstacles, your loft and where you might get good signal (it's not always the most convenient place within the loft space), the condition of the aerial gear and cabling etc etc it could be that your present aerial might be struggling with picking up the transmissions not only because the aerial is old, but because the goal posts have moved.

To add complications, too much signal can cause pixelation just as too little does. That's why I mentioned amplification. I've been to sites where the home owner had an original analogue installation amplified to better pick up the lower-powered digital transmissions before DSO, but never got rid of the amps after digital switch over once the digital transmission power increased. That caused a few issues where newer TVs had more sensitive tuners.

Putting an aerial in a loft will knock off around 5-6dB from the reception power on average. The losses can be higher if the alignment means that the aerial is pointing through the lofts of adjacent homes, and you'll also see the losses increase when the roof is wet. None of this is a problem for somewhere with very strong signal (high field strength). But if your marginal signal outdoors is because you live somewhere with lower field strength then you might not have the margin to play with.

Keeping the aerial outdoors can offset these losses before they occur, and changes in the frequency range of signal transmissions means that something like a Group K (21-48) or Group T (21-60) Log Periodic aerial might would offer a much lower wind loading whilst also being a better match for the new signal distributions.

From the ATV site, their Log 36 would be a good universal choice.

[Murph7355]

Aerials are witchcraft.

Too many factors to give anything concrete to your questions IMO. IME the only way to see is to try it.

Ours was on a massive post on the gable end. Ugly as sin so I spent a lot of time with numerous aerial types and very careful positioning. Now have a good enough signal in 3x main viewing rooms.

The others (two) are a bit too shaky, which is either the coax run to them or the tuners in the TV (one is almost certainly the latter). However, I've covered that by having a network tuner (HD Homerun) up near the aerial and use a Firestick app for TV in the two shaky rooms (far less hassle than trying to run new coax).

[Lord Flashheart]

Thank you the information here. Plenty for me to think about while my wife complains about missing half of Coronation Street.

[mgv8]

The biggest common problem is connectors (as said below). Both water in connectors, number of connectors as signal loss in connectors can be high. Next is if the cable is old and can move in the wind, as a single core copper is can brake. Last in most cases the aerial does not need to be anywhere near as high up as people put them and so lowering it can improve things over time.