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TELE-satellite International — The World‘s Largest Digital TV Trade Magazine
— 09-10/2012
— www.TELE-satellite.com
Toolbox software, you can only choose
between ports 1 to 10. I had to call up
the Windows driver manager in order to
change the COM ports so that in the end
COM1 was available and my PC was fi-
nally able to detect the DS2400T.
I could hardly wait for the software to
start and when it finally appeared on my
monitor I was almost lost for words by
looking at the endless range of options
it offered. It happens so often in life that
we think ‘too little, too late’, but with the
Toolbox software Deviser has come up
with the exact opposite and ‘too much,
too soon’ almost sprang to mind. Then
again, ‘too much’ never gives us reason
to complain! It’s not only possible to edit
channel lists and load measurements
that were performed with the DS2400T,
you can even make measurements di-
rectly with the software and an attached
DS2400T. Take a deep breath and find
out which measurements we’re talking
about:
• Frequency measurement
• Spectrum analysis
• Bar search
• Tilt
• Level/strength
• QAM
• Ground loop
One reason I was positively surprised
by this option was that it would be pos-
sible to use RDP (Remote Desktop Proto-
col) to remotely diagnose an installation
via the Internet. This way it is possible
to permanently monitor a broadcast cell
or head end, for example, from an op-
erations centre. In general, one would
use dedicated rack hardware for such a
purpose, but it’s great to know the small
DS2400T handheld meter from Deviser
can be used just as well, if need be.
Furthermore, the DS2400T Toolbox
software allows downloading measure-
ments from the device to the computer
and then graphically enhancing and sav-
ing them onto the PC for creating sophis-
ticated documentation for your meas-
urements. The built-in channel list editor
is very easy to use and we were able to
set up customised channels lists without
consulting the user manual.
It goes without saying that all configu-
ration parameters of the meter can be
adjusted with the help of the DS2400T
Toolbox software and for those looking
for another extra special treat you can
even load the current display content of
the meter onto the PC. Here we finally
discovered a small flaw which proved
that our hunting instinct was still intact:
Whenever we tried to download the cur-
rent display content we were met with an
error message indicating that the picture
could not be saved. We tried it on two
different PCs but the result stayed the
same. To be honest, I didn’t have a clue
as to what was wrong, but at one stage
I came up with the idea of running the
software as administrator with all per-
missions associated with that. Et voilà,
all screenshots were transmitted to the
PC without even the slightest problem.
The reason for this detour is as follows:
The Toolbox software attempts to save
all pictures to the installation directory,
and this is where Windows7 has some
objections, since this is a directory that
requires administrator permissions. No
matter how hard I tried, I could not suc-
ceed in trying to convince the software
to access another user directory, so the
only thing I could do was change the per-
missions of the installation directory so
that – in addition to the administrator –
all users would have write privileges as
well. Not the most efficient solution, but
at least one that worked nicely for us.
Side-by-side comparison
with our reference meter
No signal meter leaves our test center
without being subjected to a side-by-
side comparison with our in-house refer-
ence meter. The values indicated by the
DS2400T did not differ significantly from
our reference values. The chart below
shows the results for the DVB-C tran-
sponder at 690MHz, which is a popular
transponder of the TV CABO/ZON cable
System Level
(dBmV)
MER Pre-BER Post-BER
DS2400T 59.5
35.6
<1E-9
<1E-9
Reference
57.5
34.0
<1E-9
<1E-9
Table 1.