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"Watch all of your favourite shows and sports while afloat"
A typical day on the boat.
Since early morning, we have been on the water, cruising at
moderate speed to our favourite anchorage. Were hot and a little
salty, busting for a shower, a cold drink, a grilled steak, and a
comfortable place to sit, eat and chat. And of course a television,
so we can watch the big game or catch up on what has been happening
in the world.
Since our ancestors walked upright and learned to use tools, we
humans have longed to be warm and dry, well fed, and, no doubt,
entertained. In today's world, entertainment is one way that we
relieve our tension, and our hunger for it is the reason we see at
least one TV on nearly every new boat over 25 feet.
We are accustomed to getting our favourite weekly shows and sports
specials offered by cable and satellite systems at home, but
enjoying these diversions while we relax in the natural pleasures of
remote locations, in our favourite anchorage on the boat is quite
another.
The answer to our entertainment needs has come in the form of small,
lightweight, and relatively inexpensive satellite receivers. Were
talking about stabilised tracking antennas, which react to motion so
quickly and through such a large degree of tilt and swivel that we
can watch TV while the boat is underway, at speed, in normal sea
states.
Once upon a time, only cruise ships and super yachts had satellite
TV that functioned at sea. Stabilised tracking antennas were large
and heavy, in part because the gyro and drive mechanisms were large
and heavy, as were the components that captured the signal and sent
it to the receiver.
Thanks to compact, rugged and sophisticated marine Satellite
Antennas from companies such as Ocean TV (www.oceantv.com.au)
and SatVision (www.satvisiontv.com.au),
boats as small as 20 feet or 6.5 metres in length can how have
access to HDTV Channels from Pay TV providers and VAST Free to Air
in Australia.
These antennas work while underway, while at anchor or in docked at
a marina, delivering quality equal to what you would expect in a
high end system at home.
There are many sizes available for the boat owner, from 32cm
all the way up to 110cm. Each size will offer more features,
and a larger cruising reception area. Most antennas can work
on 1v to 30vDC, or 110v to 240v AC.
To the left is a Ocean TV O45M (45cm Dish Size with Multiple
Outputs). This Brand and Model has successfully been used by
Game Fisherman at Lizard Island in Far North Queensland by
commercial Samon Fisherman at bottom of Tasmania and Pro Tuna
fisherman as far West as the South Australian and Western Australian
Border with Pay TV. The VAST FTA has a little smaller coverage
area. Western Australia is covered by a Spot Satellite Beam
allowing coverage Hundreds of kilometres North and South of Perth.
Technology has allowed the downsizing of satellite TV antennas, and
since that time, the manufacturers have improved the performance
from the top down. Domes these days are lightweight and rugged, yet
allow the signal to pass through almost unimpeded. This extends the
area of coverage and improves reception in bad weather, one of
satellite TV's unavoidable shortcomings. When the Antenna is
installed correctly, the drive motor that rotates and tilts the dish
is so quiet that you'll likely never hear one at work unless you're
standing next to the dome.
How Do they Work
Most important to the remarkable performance of these small antennas
is the efficiency of the components that capture the signal and
reflect it to the low-noise block (LNB), from which it enters the
receiver to be transmitted to your television. Both
Ocean TV
and
SatVision
use Australian Specification high gain broadband LNB's while some
other companies do not.
Signals from the satellite strike the reflector dish, the concave
component similar to those on rooftops all over the country .
Unlike the dish of a household antenna, which is at least 60 cm
in diameter and deeply concave, the dishes of modern marine antennas
are smaller and flatter, which lets them function at a higher gain
and efficiency. This style of dish uses a larger percentage of its
surface to reflect the signal, further improving efficiency. It also
lowers the centre of weight in the antenna, which makes it more
stable and able to respond quickly to the boat's motion.
Like almost everything else in this world, the gyroscopic
stabilizers used in these antennas aren't a new idea, but their
small size and light weight are. They react to a boat's pitch and
roll at 25 to 35 degrees per second and respond to changes in
direction (the azimuth) at up to 90 degrees per second, keeping the
antenna on the satellite's beam and the picture on the TV intact.
The range of azimuth is unlimited and the tracking continuous.
The signal bounces off the reflector, and the splash plate on the
end of the feed tube captures it via the feed window. The feed
window is made of a low-loss permeable material. Glass was
originally used, but advances in plastics, have allowed composite
materials to be used that do not degrade the signal. The signal then
travels down the feed tube to the LNB.
According to satellite-system manufacturer Ocean TV, the
stacked LNB is the smallest (half the size of the standard LNB in an
14cm antenna), lightest, and most efficient type. It reduces
electronic noise and loss of signal strength. The stacked LNB allows
more than one channel to travel over a single cable and lets you
simultaneously watch a handful of channels if you have more than one
receiver. The standard LNB requires a cable for each receiver.
Ocean TV fits a Quad LNB to all of its antennas, while
SatVision fits a Dual LNB, both allowing Pay TV and Free to Air
to be watched at the same time with separate Satellite Receivers.
Satellites
Australia is covered by two Satellites, Optus C1 (VAST FTA) and
Optus D3 (PAY TV). OPTUS D3 is a newer satellite and has a
stronger signal, therefore it has a bigger coverage area, and
smaller Antenna sizes can be used in some regions. Optus C1 is
older and is less powerful, needing larger Antenna sizes in some
regions to receive television signals. Slowly, Optus C1 is being
turned down in power and slowly TV stations are being moved to Optus
D3, this will happen over coming years.
Both Optus satellites are in a geo-stationary position (non moving),
above New Guinea north of Australia at 156 degrees. As they do
not move, the Satellite Antennas can lock on and track boat
satellites at the same time.
What do they Cost
Ocean TV and SatVision offer a range of antennas that
are the most affordable and best value Marina Satellite Systems on
the market today. Expect to pay under $3000.00 for 32cm to under
$7,000.00 for 60cm, with 37cm and 45cm in between.. Go to our
Links Page to check latest pricing at their
websites. Installation is extra around $800 to $1000.00, but
it is also possible for a Do It Yourself Boatie to install a
complete system over one weekend. Both Ocean TV and
SatVision offer complete kits and also Phone and Email help
lines.
Well the game is about to start, so you climb into a cosy berth or
sit back on the fly bridge and hope for a close scoring match, while
the wife watches her latest cooking show in the Saloon, and the kids
are watching cartoons in their cabin. |
