TELE-audiovision - The World’s Largest Digital TV Trade Magazine - page 84

TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine
— 03-04/2014
Terrestrial Antenna
Terrestrial TV does not
offer as wide a channel
choice as satellite TV, but
it has other strong points,
namely in most countries
among the terrestrial chan-
nels you can find the local tv
channels providing informa-
tion on what is going on in
your neighborhood. Another
strong point is that setting
up a terrestrial antenna can
be a simple and easy-to-do
“Can be” does not mean
“always is”. If you want to
install a multi-element yagi
antenna with complex reflec-
tors your antenna setup will
become a rather complex
one. That’s why many people
prefer simpler solutions and
small compact TV antennas
are becoming more popu-
lar. Generally, they cannot
offer as good performance
as a full size multi-element
yagis but if you live not very
far from the TV transmitters
they can ensure a quite solid
reception while being very
simple in installation. And, if
nicely designed, they can be
more esthetic than yagis.
The Yagi U-PA fits all of the
above. Its size is quite small:
35 x 13.5 x 12.5 cm and it
is very light – ca. 0.6 kg. It
can be used either indoors or
outdoors. In the latter case
you simply attach it to a
pole with two butterfly nuts,
which are part of the pack-
age. You do not need to use
any further tools.
Its double panel radiators
are completely hidden in a
plastic enclosure so in fact
the antenna does not look
even like an antenna. That
is especially nice when you
opt to use it indoors rather
than outdoors. The antenna
is available in white or black
And what about the tech-
nical specifications of the
Yagi U-PA? The manufac-
turer promises a reasonably
wide frequency range of 470
~ 770 MHz (UHF channel 13
through 69) and a good gain:
4 ~ 5 dB. Its Half Power
Beam Width (HPBW) is very
large: 76°. This means that
when it receives a signal lo-
cated +/-38° off its center
line the antenna output will
Yagi U-PA UHF Antenna
technical performance
Small But Surprisingly Efficient
be attenuated only by 3 dB
compared to the signal com-
ing directly from the front.
Thanks to this uncommon
feature this antenna in many
cases will be suitable to re-
ceive not just one but two or
more TV transmitters that
are located in a similar di-
rection from your home. And
this means, of course, more
channels to watch, without
moving the antenna to an-
other direction.
The Yagi U-PA is not sym-
metrical – it has a front and
a back. If you turn it around
(180°) it will attenuate the
signal by 9-12 dB. In this as-
pect it is similar to a multi
element yagis.
Speaking of multi element
yagis: we decided to use one
as our reference antenna for
comparison. Of course this
big yagi had much more su-
perior parameter specifica-
tions. Its gain was 9 ~16.5
dB and thus 4 ~ 12.5 dB bet-
ter than the Yagi U-PA. We
decided to measure both
antennas to check if the dif-
ference was not greater than
our theoretical calculations.
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