BenQ S700 - Manual (Page 22)

6 Preparing Your Phone For Use
5. The standby screen will be displayed, as well as network signal
strength and the name of the network operator. You can now use the
phone.
If the phone cannot detect the network, the on-screen signal strength
meter will show no bars.
If the phone links to a network that you are not authorized to use, the
signal strength meter will show a level of zero. You will only be able to
make emergency calls.