ECOTEST DKG-21 Operating Manual page 43

The threshold level is stored in the nonvolatile memory of the dosimeter.
Switching the dosimeter on and off and replacing its battery does not change
the threshold level.
Press the THRESHOLD button and hold it down not more than 2 s after a
threshold level value and the ALARM transparency appear to check the value
of the DER threshold level.
A blinking red LED and the ALARM transparency, as well as a two-tone
sound alarm mean that the programmed DER threshold level has been
exceeded.
Important! If the process of the new threshold level programming is
paused for more than 30 s (the user presses no buttons of the dosimeter), the
dosimeter will automatically return to the mode of DER measurement. All
changes made in the submode of new threshold level value programming will
be canceled.
Notes
1 DER threshold level value of 1.0 µSv/h is set after the dosimeter is
produced.
2 A preset zero value of the DER threshold level sets off the alarm system
when the threshold level is exceeded.
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