Technoline WS 9750 Manuel D'utilisation page 58

Note: User shall insert the batteries into the third transmitter within 10 seconds of
reception of the second transmitter.
8. In order to ensure sufficient 868 MHz transmission however, this
should under good conditions be a distance no more than 100 meters between
the final position of the Temperature Station and the transmitter (see notes on
"Positioning" and "868 MHz Reception").
IMPORTANT:
Transmission problems will arise if the setting for additional transmitters is not followed
as described above. Should transmission problems occur, it is necessary to remove the
batteries from all units and start again the set-up from step 1.
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