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TELE-audiovision International —
全球发行量最大的数字电视杂志
and is the result of the appli-
cation of international stan-
dards in development and
production.
The pictures show the
measured values in the
ranges 50 to 180 MHz and
950 to 2150 MHz. These are
definitely within the preci-
sion range of the device and
the tolerance given in the
WORK Microwave Handheld
Satcom Test Source‘s certifi-
cate.
This shows that the Hand-
held Satcom Test Source
can be used in another out-
standing way: it can be used
to precisely calibrate test
equipment.
Testing
a CATV Cable Run
Another application for
the Handheld Satcom Test
Source is the testing of a
CATV network‘s cable instal-
lation. For this test we used
our own distribution network
here in the TELE-audiovision
test center.
A multiswitch with 16 in-
puts for the satellite range
(950 - 2150 MHZ) and an-
other input for terrestrial
TV (50 - 850 MHz) was used
for distribution. The signal
is then made available on
eight outputs and distribut-
ed throughout the house to
a number of antenna ports
that each provide separate
satellite and CATV outputs.
The next step was to mea-
sure the attenuation of the
signals in the satellite range,
but we also wanted to know
if the multiswitch, the coax
cable and the antenna jacks
had more of an affect on
some frequencies than on
others.
Normally, you’d use a
noise generator for this task
but they typically don’t come
with the same measurement
precision as does the Hand-
held Satcom Test Source.
If you’re thinking now
that it would be an enor-
mous amount of work in that
you’d have to check each
frequency individually, you’d
be wrong. WORK Microwave
incorporated a sweep gen-
erator in the Handheld Sat-
com Test Source that can be
set to run through a user-
defined frequency range (50
to 180 MHz and 950 to 2150
MHz). The frequency steps
can also be set (minimum of
0.5 MHz) as well as the de-
sired speed (starting at 10
ms per step).
The output level can be
set from -5 to -45 dBm. The
sweep itself can be run bidi-
rectionally: when the sweep
reaches the upper frequen-
cy limit, it turns around
