Genuine digibox, LNB or cable faults may cause a lowband problem.

Substitution of the suspect product or rectification of the fault can identify these instances. It is always a good idea to try a test box prior to exchanging a customer's digibox.

Additionally, if the installed cable is not of an approved type it must be replaced. The use of the correct quality of cable for satellite installations, or indeed any system containing digital transmissions, is vital if the best quality of signal is to be received.

Poor quality cable is very destructive of digital signals. It allows a lot of the energy of the wanted signal to leak out as well as allowing the ingress of extraneous interference. It can also create reflections and mismatches that interrupt the flow of data.

To reassure installers and their customers the CAI now maintains a list of approved cables from different manufacturers that have been tested against a quality benchmark.

A digital system will work correctly as long as the signal quality remains even, marginally above a particular threshold.

Dedicated test equipment should be used to assess how far the system is above that threshold. The further a digital system is over its threshold the fewer problems it will cause for both the customer and the engineer over time.

Apart from careful alignment and fixing of the dish one of the most effective ways of maintaining high threshold is to use the correct grade of cable between the antenna and the receiver with suitable termination.