Check the signal strength

Navigate through the menu to easily see the signal strength that you have on the mobile phone network - the example here already has the modem powered as it is in polling mode (i.e the unit has an external power source and has been configured so that you can request readings from the unit) - when the unit is in polling mode then there is a P on the top of the screen.

The unit leaves polling mode, checks the signal strength and displays the signal on the screen - orange is a UK network provider.