Huawei USB dongle
I always forget the colour of the indication light on 3G dongles, to know when its connected, and the signal strenght. Hopefully this will help:
http://bigcowpi.blogspot.com/2013/03/pi-3g-router-query-signal-quality-and.html
Green, blinking twice every 3s The USB Stick is powered on.
Green, blinking once every 3s The USB Stick is registering with a 2G network
Blue, blinking once every 3s The USB Stick is registering with a 3G/3G+ network
Green, solid The USB Stick is connected to a 2G network.
Blue, solid The USB Stick is connected to a 3G network
Cyan, solid The USB Stick is connected to a 3G+ network.