Radio Reception Digital (DAB)
Often referred to as DAB, digital audio broadcasting is the new revolution for radio offering perfect crackle free reception using a system called COFDM Coded Orthogonal Division Multiplex. However, even though this system is virtually immune to interference, to prevent any possible loss of reception you will need to ensure the following.
Ensure the aerial is suitable in that it offers good performance to receive signals between 217-230Mhz avoid using a band 3 VHF aerial designed to receive the entire band as these will not perform as well.
Install a simple Omni-directional aerial for locations close to the transmitter or a multi-element directional aerial designed for built up or fringe areas.
Ensure the aerial is installed on its side so it is vertically polarised to a suitable position at roof level, avoid mounting it to within less than a metre of other aerials.
Use quality twin screen 75-ohm coaxial cable with shielded and crimped coaxial connections.
If the fault has just occurred, check the dish has not
moved and that there are no local obstructions such
as building work; trees; etc. gone up or grown
noticeably taller since the dish was installed. Ensure
that there is a clear line of sight approximately 30
degrees upwards from the satellite dish position.
When combining DAB signals to serve a distribution system ensure that all components that make up the system such as combiners, splitters and amplifiers are designed to operate at band 3 frequencies.