An aerial filter is used to prevent unwanted signals from reaching your equipment, whilst allowing the wanted ones to pass through unaffected.
Some filters may need to be installed before any amplification, while others should be installed directly before the receiving equipment.
A qualified installer should be able to suggest the best option for you.
High-pass filters
Filters stop unwanted signals from radio amateurs and CB enthusiasts which can interfere with TVand radio reception.Since many amateur transmissions are lower in frequency than TV and FM signals, a high-pass filtercan be fitted to the receiver to prevent the low frequency amateur signals from reaching itand causing problems. High-pass filters are a common component in what are known as ‘TVI' filters, sometimescalled ‘TETRA' filters.
Band-Pass filters
Band-pass filters allowonly a range of required frequencies through, rejecting all others. Band-pass filters must be specified for the correct use. For example, using a television band-pass filter on an FM tuner will prevent reception of FM signals - and vice versa.
Braid Breakers
Braid-breakers work by preventing low frequency signals from reaching TVor FM equipment down the outside of the aerial cable. If you have severaldevices connected to your equipment, you may need to fit filters to the inputs of all of them.
Ferrite rings
Sometimes strong, amateur signals can interfere with audio equipment as well as TV or radio. This usually happens because the loudspeaker wires or mains cables act as ‘aerials' and conduct the signals inside the case. You can wind a short section of the cable in question around a ferrite ring using a number of turns, and to do so as near to the hi-fi /TV/radio as possible.
Qualified Installer
The tv cannot recommend individual Installers. TheCAI ()is a recognised trade body which will be able to put you in touch with one of itsmembers in your area.
