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— 1 -12/2012
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the AntenasCostelo M-1038
gave 3 decibels more than
the rod antenna (50.1 dBµV
vs. 46.9 dBµV). That’s quite
something. After switch-
ing the analyzer to meas-
urement mode, the differ-
ence even increased (50.0
dBµV vs. 46.6 dBµV). For
your reference, our roof
antenna produces over 62
dBµV on that channel. Also
the signal-to-noise ration
looked significantly bet-
ter for M-1038: 34.5 dB vs.
30.9
dB. Although, we did
not plan it initially, we con-
nected M-1038 to our TV-
set. The picture was noisy
but readable.
Then we got bolder. we
tried to go live and catch the
real digital channels which
in our location transmit on
634
MHz and 666 MHz. But
the signal from both anten-
nas was too weak to meas-
ure it with our signal ana-
lyzer. But then we realized:
the AntenasCastelo M-1038
can be mounted outside!
We rushed up to our balco-
ny and mounted the M-1038
outdoors on a small mast.
The improvement was no-
ticeable at once. The signal
on 634 MHz rose to 51.6
dBµV with MER equal to
26
dB. The second signal,
on 666 MHz, was some-
what weaker and it rose to
42.9
dBµV with MER equal
to 16.2 dB. How would
this result on a tv screen?
We decided to connect the
antenna to our DVB-T re-
ceiver. The multiplex trans-
mitted on 634 MHz was re-
ceivable but from time to
time our receiver notified
us that there is a too weak
signal. The other multiplex
on 666 MHz was below the
reception threshold of our
receiver.
We compare those results
with the simple rod anten-
na. As could be expected,
for both transponders, the
M-1038 was better. It pro-
vided stronger output by 3
decibels for 634 MHz and
even by 5.5 decibels for
666
MHz. Naturally, MER
was also better: by about
1
dB and 2 dB respectively.
Using a single rod antenna
we would see none of the
two DVB-T signals while the
M-1038 was good enough to
catch at least one of them.
To sum it up: the M-1038
like every other small an-
tenna can not replace a full
size external antenna. How-
ever, if you live relatively
close to the transmitter, es-
pecially on a high floor, such
small antenna could do the
job. It is very easy to install
and everybody can do that.
If only possible though, try
to mount it outdoors as this
improves its performance
significantly.
The
AntenasCastelo
M-1038 proved to be visibly
better than that of a simple
improvised rod antenna in
the center of the terrestrial
band. However, being very
simple in design, the M-1038
could not beat the rod an-
tenna for every frequency.
Performance of such simple
designs depend on the ratio
of RF wave length-to-anten-
na length. So it is obvious
that for some frequencies,
170
millimeters of rod an-
tenna could perform better
than M-1038.