Wahl Heat Spy DHS520, User Manual

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Wahl DHS520 User Manual
To fit a dark filter and close-up lens combination, unscrew the protection window
from the lens assembly and replace it with a close-up lens (first), followed by
a dark filter. As there is now an extra optical element in the sight path of the
instrument, a window compensation factor of 0.93 must be entered to allow
for the associated energy losses.
6.6 Eyepiece Optics
target reticule
(1/3° circle)
Not to scale
display panel
temperature
reading
315016
Fig. 16 Wahl DHS520/520B Eyepiece Optics
The eyepiece allows you to look into the thermometer and view the target
scene. Accurate target definition is provided by the wide angle (9°) field of
view and small, clearly defined (1/3°) target reticule.
The eyepiece can be focused manually to match each user’s eyesight
characteristics:
1) Use the viewfinder to view a plain, brightly lit background, such as a
blank wall.
2) Rotate the rubber eye cup to bring the reticule circle to the sharpest
possible focus. The eyepiece is now adjusted to your eye.
3) Adjust the main focusing ring to bring the target scene to the sharpest
possible focus on the reticule circle.
When a temperature reading is taken (the trigger pressed), the measured
value is displayed in the eyepiece display panel. The temperature is displayed
in the units selected from the Main Menu.