Medion MD82144 Manual Del Usuario página 118

'Keypad locked' will appear if these keys have been pressed for a short
time, because the keyboard will have been locked against pressing for a
short time.
Calling in-house
You will be able to call all the other handsets on the same base station
without paying charges if several handsets are registered on a base
station (see Registering handsets).
Press the Int. key.

All the other handsets that are registered on the base station will appear
on the display (Handsets 1 - 5).
Select the required handset with the left or the right key and press the

Talk key.
The required handset will now be called.
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