TV Aerial hardware

TV Aerials

Aerial hardwareThere are hundreds of different TV aerials from different manufacturers, ranging from cheap contract wideband aerials upwards, a genuine Digital television aerial contains a balun which matches the signal to the aerial download and it will be benchmarked, the only genuine Digital television aerial which doesn’t need a balun is a log periodic due to it’s design. The choice of aerial is critical, remembering you only need enough signal.

Coaxial Cable

Like TV aerials there is a wide range of coaxial cable available, from very cheap imported cable to approved digital coax cable which has copper braid and copper foil, good quality cable loses approx 0.2dB per metre, the very ‘worst’ cable can lose 10 times that!

TV Aerial Amplifiers

Frustratingly called boosters, the purpose of a TV aerial amplifier is to divide up a good signal to deliver to more points or amplify a signal to overcome a long cable run. If there is a borderline television aerial signal, an amplifier can be used as a last resort, then it is the most efficient to amplify near the aerial (usually within 1m) using a masthead amplifier, this will amplify the signal before noise and interference is picked up along the length of the cable. We receive a lot of requests for amplifiers to solve reception problems, but if the TV signal is poor, all that happens is the noise and interference is amplified.

Referring back to the fact that the TV aerial only needs to be good enough, a signal only needs to be amplified just enough – that is why television aerial amplifiers can be bought with different gain values (measured in dB) variable gain amplifiers tend to introduce more noise on to the system than fixed gain.

Fittings

Good quality fittings, we use crimp f connectors, screw on male and female coax connectors and where required screened outlet plates, a common practice is to run directly through the wall using a grommet to the equipment this reduces connections and the potential of losses.

Brackets

Most television aerials are fitted on chimneys, the recognised method is a corner bracket and lashing kit – chimneys shouldn’t be drilled for brackets. Often a new Digital TV aerial will be physically bigger than the aerial that is being replaced; this increases the stresses on the brackets and lashing kit; unless these are in exceptionally good condition and suitable for a new aerial they should be replaced.

Summary

All areas of an installation can be checked with an aerial signal meter, the height, direction and type of aerial can change results; if the signal isn’t being received at the aerial nothing will get it back, losses from the cable can be calculated, no unexpected losses from connections can be checked, as can the correct gain from any amplifiers etc.
At Prossers we only use benchmarked aerials, double screened cable and good quality fittings to improve reception and reduce losses we do this as we pride ourselves on a good quality installation.

DIY Aerial Installation

Potentially a do it yourself installation can be undertaken; point the aerial in the right direction and scan for channels, if all the channels found great – if not what then? Some televisions can check the signal for you, it is the quality that is more important than the strength; if your Television has this feature it is important to check on each digital multiplex, focussing on the channels where reception is poor.

If problems persist; where the problem lies may now become more difficult to diagnose without the necessary test equipment. We receive calls to DIY installations – sometimes we can correct a fault, sometimes, unfortunately we have to recommend starting again.