ISDN ANALYZER D1080 - messkom.de

ISDN ANALYZER D1080 USER’S MANUAL REV. 5
For a functional characterization of the line, a series of tests
(transmission quality measurement, traffic generation) must be
carried out, first without and then with signal attenuation (0dB
and –3dB setting, respectively).
In case of negative results with signal attenuation, the conditions
of the line are barely acceptable, with possible malfunctioning of
the access once the NT socket has been installed.
9.1.2. Programmable load
The instrument is equipped with a programmable load that can be
set with energy consumption ranging from a minimum value of
30mW to a maximum of 2500mW. The standard consumption of a
NT plug is normally about 1100mW, which is the default value of
the instrument. To simulate the load of a NT-Plus plug, a wattage
of about 1400mW can be set. The programmable load can be
disabled by setting the NONE value. This makes it possible to
measure the maximum voltage of the line, which depends on the
type of exchange connected to the tested access.
The instrument is locally supplied either by the internal batteries
or the external AC/DC adapter and therefore does not manage the
lack of local supply at 230Vac.
9.1.3. Minimum voltage
This field is used to set the minimum voltage value under which
the instrument resets its line interface and starts again with a
‘cold’ activation.
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CHAPTER 9. “U” INTERFACE