TÉLÉ-audiovision- Le plus grand magazine au monde sur le commerce de télévision numérique - page 134

TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine
— 01-02/2014
tion was possible. On the down side, I
found that a maximum of three offset
antennas could be mounted, since the
space required by the feed arms and
the LNBs did not allow for a fourth an-
tenna. Still, at this point I simply re-
fused to give up and thought long and
hard about how I could accomplish a
small and – almost – invisible antenna
farm on my balcony after all.
I decided to get four flat antennas.
The models I chose were not flat an-
tennas in the true sense of the word,
but rather prime focus antennas that
feature a metal dish behind the plas-
tic covering on the front, which means
that the LNB is actually positioned be-
hind the antenna. This a very smart
design that allows for virtually flat an-
tennas which still achieve a good signal
gain that is in line with most conven-
tional 60cm antennas.
Genuine flat antennas, on the other
hand, use a multitude of small patch-
es that are connected to each other.
Signal gain with such a construction
can only grow logarithmically with re-
gard to the number of patches that are
used, which means that those anten-
nas are usually only available in small
sizes (comparable to 60cm antennas)
and are more expensive – one of the
reasons why I did not opt for genuine
flat antennas.
When I tested only one antenna for
the first time the results I obtained
were truly promising. I was able to re-
ceive a perfect signal right on my bal-
cony, behind the balcony wall.
Next, I had to mount the remaining
6. Inside the flat antenna: It’s more like a
prime focus antenna with reflector. The
LNB is mounted behind.
7. Size comparison between a 60cm offset
antenna and a 60cm prime focus flat
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