Wireless network signal is very important when you use a BlackBerry. If it turns out the SOS signal indicator shows the symbol, it means there's no signal around you.
Better to just turn off the handset rather than to repeatedly search for the signal and battery to be quickly discharged because of it.
There's a good idea to frequently check the network signal strength in your surroundings. The trick, press the ALT key and press the N - M - L - L. Signal indicators are now turned into numbers. If the signal shows a value outside of the range of -40 to -100 DBMS, it means a sufficient signal strength is not obtained to access the BlackBerry network.
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