Proper Cabling: Place, Secure and Terminate Coaxial Cable

Digital signal get lost a bit over cable transmigration. A proper cabling reduce the lost wherever possible. Cabling methods are one of the most ignored key practices in antenna installations. In many cases we see cabling like this:

The image below illustrates various cabling methods applicable for brick, timber, Hardi-panel, fibro cement and aluminium walls.

Invisible is best
Wherever possible the coaxial cable should be out of sight, running through roof spaces, down internal wall cavities,

and under floor spaces. This also helps protect the cable against accidental damage but doesn’t guarantee that other trades or contractors won’t damage the cable when servicing other utilities.

When the cable cannot be fed through cavities then it can be placed within a box channel conduit. This is manufactured to be run as unobtrusively as possible along skirting boards and at the corners of walls.

Drip loops
To prevent the ingress of water a drip loop is to be provided at the point of entry to the dwelling for all external cable runs. The point of entry is to be sealed with an approved sealant as shown below.

Fastening intervals:Remember that any change in the shape of the cable will cause issues with impedance. Secure cable at unequal distances: Each point on a coaxial cable that is secured by means of either a cable tie or cable clip is subject to a small amount of pressure being put on the dielectric resulting in slight changes to the nominal impedance at those points. Whereas the change is small and not easily recognizable under test the cumulative effect over distance can cause signal reflections and reduce the carrier to noise ratio.

This will effect the quality of the signal being received at the equipment. One way to reduce the overall effect is to secure the cable at uneven distances to minimize the cumulative effect on the cable.

Cable damage due to a lightning strike entering the cable after hitting the ground Industry practice is to secure the cables at 500 mm intervals. The recommendation is to modify those distances by between 50 and 100 mm. For example, 450 mm then 500 mm then 550 mm then 450 mm and so on.