Megger TDR1000/2 Guide De L'utilisateur page 6

Introduction
the cable. The TDR1000/2 has internal matching
networks to allow testing of 25, 50, 75 and
100 cables. (These typically correspond to power,
coaxial data and data/telecoms cable). By selecting
the TDR impedance closest to that of the cable
under test, maximum power can be transmitted
into the cable allowing long cables to be tested.
The velocity factor of the TDR must be adjusted
to match that of the cable under test, allowing an
accurate distance measurement to be read directly
from the instrument. Where the VF of a cable is
not known, but the length is, the cursor can be
set to the end of the cable and the VF on the TDR
adjusted until the correct cable length is displayed.
Other configuration settings include changing
the distance units between metres and feet,
changing the propagation velocity units between
a ratio and a distance per microsecond. Display
contrast is fully adjustable to compensate for all
viewing conditions. A backlight aids viewing in low
ambient light conditions.
The instrument can be powered by
manganese-alkali, nickel-cadmium or nickel-metal-
hydride batteries. All cells must be of the same
type.
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