Sat in the city:

24
Special DigitalLife
INFODIGITAL December 2008
A
small satellite key and a suitable
receiver is all you need to
access hundreds of programmes
in your home. The location of ASTRA
19.2° East alone offers a colourful
and international selection of several
hundred digital free-to-view satellite
programmes from all over the world.
Moreover, several further hundred pay-
Sat in the City
DigiDish 33: Really large
selection from small
satellite antennas
per-view encoded channels are also
available. The parabolic antenna necessary
for accessing the same is also considerably
smaller than those required
for analogue transmissions:
This is how small the DigiDish 33 is.
The digital satellites, namely in comparison
to their analogue peers, boast a
considerably higher output power.
The best example of this is the TechniSat
DigiDish 33. The mini antenna,
which has a diameter of barely 33 cm,
appears diminutive to the eye. However,
its performance is anything but.
Receiving what previously required a
parabolic antenna 65cm in diameter
is no major problem for the newer
and smaller version.
Principle behind receiving
satellite signals
To receive incidental television signals,
which are transmitted via satellite, on
the one hand we have the concave
antenna and on the other, the aforementioned
(round) LNB, in which frequencies,
thanks to the way the curve
is constructed almost as in a burning
glass. When learning physics (optics)
in school, we all doubtless vaguely remember,
that the angle of incidence is
also the angle of reflection. The same
ratio applies to the incident signals:
each satellite has a specific position
in the orbit and thus transmits its relevant
“Footprint” onto the correspondingly
positioned antenna. Since the
myriad range of satellites around the
world each have different orbit positions,
their signal angles also vary and
can consequently not all be picked up