Freeview Help: Interference

A weak signal strength is the most common cause of picture break-up. Your Freeview receiver just can't get enough signal to hold a decent picture.

Most Freeview set-top boxes and TV sets have an on-screen signal strength screen. This can be useful in working out how good your incoming TV signal is. You may have measurements for both Quality and Strength - the measurement for Quality is very important - if this is high, then you're likely to get good pictures even if the strength is much lower.

If your signal is weak, check your coverage. If you're in Freeview coverage, a weak signal could point to an aerial issue.

You should find the on-screen signal strength meter somewhere in one of the menus. Check your receiver's manual for details.

It's also worth re-scanning your Freeview channel list a couple of times too.

Are your neighbours affected by interference?

• Yes: Could be an issue with your local transmitter, the weather, signal in your area, digital switchover transmitter updates, or local interference
• No: This would indicate a possible problem with your aerial or cabling
  
  

Sorting out your aerial cabling can make a serious difference to your reception. Just replacing your flylead from the aerial socket on your wall to the Freeview box show improvements.

Use a high-quality co-ax aerial cable with gold-plated co-ax connectors (such as those from Maplin), don't run your aerial cable anywhere near your mains cables, and don't use longer cables than you actually need.

Another option to try (although it didn't work for us), is to wind your aerial flylead through a 'ferrite ring'. These are designed to cure electromagnetic and RF interference at the source. Available for about a pound from Maplin Electronics.

For more help on this, see our cabling advice.

Make sure your aerial isn't damaged, misaligned, or not up to the job. For best results, you need a good quality rooftop aerial, pointing directly at the appropriate digital transmitter.

For aerial advice, see our aerial advice.

In some cases, a booster / signal amplifier can improve your reception and reduce interference, most commonly if you're feeding lots of TVs / recorders around the house.

Note that in cases of low signal boosters are less effective as they amplify noise as well as signal. See our boosters and splitters page for more.

If you're splitting aerial cables so that you can get TV in other rooms, consider a mains-powered booster with multiple outputs. This can help to overcome loss in the cables.

It's also worth trying a basic connection (i.e. removing feeds to other room or other equipment) to see if the extra cabling / connectors are causing interference

This is another major annoyance - a common example being picture breakup when a light is switched on, the washing machine is running, a car or bus drives past or there's other electrical activity in the area.

Freeview can be prone to electrical interference, and here are a few hints to help you cure this:

• Keep your aerial leads and connectors as far away as possible from electrical mains leads as possible.
• Make sure you're using good quality leads to connect from your aerial to your receiver, and from your set-top box to your TV or video. For a new extra pounds, a good quality aerial flylead cable with a gold-plated connector from Maplin Electronics may help.
• If you've got lots of joins, connectors or unshielded adapters, these can make a weak link in your setup. Make as few joins as possible, and keep joins away from all mains cables.
• If these don't work, a good quality external roof aerial with good quality unbroken cable straight to your set top box should be the answer.
  
  

Bad weather can have an effect on your reception - strong winds blowing your aerial will affect your signal, as will heavy rain especially in weak signal areas.

Good, sunny weather can have an effect on your reception if you're in a weak signal area, due to high pressure atmospherics.

Do you live close to a taxi firm, radio ham or police station? Some radio transmitters kick out "RF" which can cause TV interference.

You may also want to get yourself a TVI RF filter, or try ferrite rings to remove this unwanted noise. Other tips in this section can help to screen out RF as well as electrical interference.

Equipment such as video recorders and some set-top boxes 're-broadcast' their signal via aerial cable. This is known as 'modulating', and allows equipment without SCART sockets to view the equipment's output.

If you're seeing interference to channels, this could be being caused by something in your setup clashing with other channels. See our advice on "RF channels".