T
ARGETING
Page
47
Electronic Copy of LTI’s Impulse User’s Manual 8
th
Edition © October 1998
Notes on Measurement Modifiers
•
Due to hardware constraints, gates work best
when the short gate value is 5 to 6 meters (15
to 20 feet) beyond the targets you wish to
reject.
•
Gates can be particularly useful when trying to
target an object through a window (or fog).
Measuring the distance to the window, then
setting the short gate 5 to 6 meters (15 to 20
feet) longer than that distance will ensure that
you are targeting the object beyond the window,
and not the window itself.
•
When the instrument is powered off (or turns
itself off), the gate option is reset to OFF, but
gate values are retained in memory. Offset and
filter settings are saved upon powering down.
•
When using gates and offsets together, keep
the following in mind: Gates and offsets are
additive; a gate will reflect the same offset that
is applied to the target. Say, for example, that
you set the range offset to 15 meters and the
short gate to 30 meters. If you scroll back to
view the short gate value, it will then read 45
meters. But remember, the 45 meters is from
the virtual measuring point 15 meters behind
you. The gate is still 30 meters in front of you.
•
The range offset has the same additive effect
on the long gate setting.
•
A range offset does not affect ranges in HT
mode. And, although the range offset will not
alter the physical location of your gates, it will
alter the gate values seen on the display, so
you may want to
