ECOTEST DKG-21 Operating Manual page 39

The blinking digits on the dLCD indicate that the infrared port is active.
As soon as data exchange with the PC is finished, the dosimeter starts
accumulating the dose history with the preset interval.
Otherwise, the dosimeter starts operating in a stand-alone mode with
integral dose accumulation without dose history accumulation.
Press the MODE button once again and hold it down for 4 s to switch the
dosimeter off. If the dosimeter is switched on in a stand-alone mode, i.e. no
data exchange with the PC is done, the dosimeter will switch off. If during
switching it on data exchange between the dosimeter and a PC took place, the
effort to switch the dosimeter off would only activate the infrared port
for 15 s.
4.3.3.2 Switching dLCD illumination on/off
To switch on the dLCD backlight, press the THRESHOLD button twice
(the time between presses should not exceed 0.5 s). To switch it off, press
the THRESHOLD button twice once again.
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