General IRTC40 Mode D'emploi page 5

display indication of LOW, targets hotter
than the reference temperature ± T
produce fast beeping and a display
indication of HIGH, and targets within the
"Goldilocks" zone—not too hot and not too
cold—yield silence and a display indication
of NORMAL.
The IRTC40 automatically enters
conventional (non-scanning) IRT mode
when you squeeze and hold the trigger for
three seconds. To enter scanning mode, you
set a reference temperature and a "setpoint
bandwidth" representing twice the value of
T. In practice, what most professionals
use as a reference is something they
consider at "normal" temperature—an
interior wall of a room, for example. Setting
the IRTC40's reference temperature to this
value requires that you point the gun at the
reference object and press a button on the
front panel. Doing so causes that
temperature to appear at the right of the
term REF on the LCD.
In scanning mode, the setpoint bandwidth
can be set to any of three values—
1°F (0.5°C), 5°F (3°C) or 10°F (5.5°C).
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