TV ANTENNA INSTALLATION GUIDE
A guide to antenna installation is provided in the following information,
however, we do suggest that professional installers be employed to erect
antennas.
CHOOSE THE RIGHT ANTENNA
Outdoor antennas are preferred to the indoor variety whose performance
can be affected by wall insulation, plumbing, electrical wiring, roofing
materials and even people moving around a room.
Choice of an outdoor antenna depends on the channels provided in your area:
Very low,Very High Frequency (VHF)
- Band I antennas for channels 0 to 2
- Band II antennas for channel FM
- Band III antennas for channel 5A to 11
- Multi-channel VHF antennas for channel 0 to 11
- Band IV antennas for channels 28 to 35
- Band V antennas for channels 39 to 69
- Band IV/V antennas for channels 28 to 69 (in circumstances)
ANTENNA SYSTEM
The following information is provided as a guide. For the
best results, you should ask a professional antenna installer to advise on and,
if necessary, install your UHF antenna system.
Television signals are strongest, and reception is usually the best, when the
station's transmitting tower is in clear line of sight with the home receiving
the broadcast. Mountains, buildings or trees, which block this line of sight,
tend to weaken and degrade the received signal; the signal also becomes weaker
as it travels further from the transmitting tower. All of this means that, in
difficult and/or distant receiving situation; a higher 'gain' antenna may be
required.
'Gain' is one measure of an antenna's ability to receive signals; the weaker the
signal you are trying to receive, the more 'gain' your antenna should have. In
practical terms, higher 'gain' antennas are usually longer, and have more
elements or cross-pieces.
It is important to realise that an antenna's 'gain' can vary from channel to
channel; for example, an antenna's advertised 'gain' rating may apply to channel
28, but the 'gain' may be much less at channel 55. Make sure your antenna
supplier guarantees that the antenna you buy is suitable for all the channels in
your area.
ADJUSTING THE ANTENNA
The boom (backbone or spine) of the antenna is pointed
towards the source of the broadcast, the transmitting antenna. The elements
(cross-pieces) should be adjusted to be horizontal or vertical depending on
whether the transmitted signal is horizontally or vertically polarised.
tvantenna.com.au can advise on the polarisation of your service. The direction in
which the antenna points and its height should be carefully adjusted to obtain
the best picture. Small changes can make a big difference. "Subject
to area you are calling from."
If your picture is spoiled by 'snow', by 'ghosting', or by both of these
undesirable effects, these pointers may help:
- 'Snow' or severe 'grain' in the picture is caused a weak signal, a poor antenna system, the set itself or by a combination of these.
- 'Ghosting' is caused by a signal arriving at your antenna from two or more different directions. These multiple signals cause multiple images (or ghosts) on your screen; they occur when the main signal is reflected off buildings, mountains or even aeroplanes.
ANTENNA CABLES
If you are starting from scratch, or if your present VHF reception is not very
good, you should study this guide carefully before attempting an installation
and seek further advice if you are not confident about all the details.
UHF conversion or adaptation of a VHF antenna system connected to multiple TV
sets is more complex, and you should always consult a reputable antenna
installer who has experience in the installation of these systems.
The correct antenna cable will deliver the television signal from the antenna to
the set, with relatively little loss of signal level or quality. Installing the
correct cable is as important as choosing the correct antenna. The main points
to remember are:
- Conventional ribbon-type VHF cables are not suitable for UHF.
- You need to use a low-loss coaxial cable
A good quality 75 ohm low-loss UHF coaxial cable is
recommended. It is suitable for both VHF and UHF signals and is easy to install.
It has greater resistance to the weather and is less likely to pick up unwanted
signals than an unshielded ribbon-type cable.
Coaxial cable on an existing VHF antenna installation may not be suitable for
UHF reception and should be treated with caution.
Most new television sets are fitted with one (combined UHF/VHF) input socket for
coaxial cable. The cable must be fitted with a proper coaxial plug to fit these
sockets.
COAXIAL CABLE
Use low loss coaxial feeder cable to connect the antenna to the TV set. This cable should be suitable for the new digital television service. This type of cable is suitable for both VHF and UHF signals.
We
recommend rg6 quad shield for the best result.
Use the shortest possible length of cable as this will mean reduced signal loss.
Prevent wind damage by attaching the cable firmly to the outside wall. Form the
cable into a half-loop where it enters the house so that rainwater will drip
off. Seal the entry point with a waterproof sealant.
AMPLIFIERS
If you use a splitter you will find that signal strength is
reduced and that you may need a masthead or distribution amplifier. This
equipment boosts the signal before it is fed into the splitter and ensures that
signals of adequate strength are supplied to each connected set.
A professional antenna installer can measure the signal strength at your home
and recommend the type of equipment needed.
Combined Splitter/Amplifiers are also available.
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We hope this information has helped you get a better idea of what is involved
in correct antenna installation. We, of course, understand these issues
and more and can supply you with the best picture your television is capable of
displaying.
Anybody wishing to install their own antenna can purchase all required equipment
from us at a very competitive price.
Phone :0500525256 local in Australia
Outside Australia :61352322255