By default, you will see the signal strength in graph format. You can turn this into a numeric value. Here is how to do that

• Rather than looking at signal bars, you can change the coverage indicator to show 'signal strength' in digital (dBm) format. While at the home (icon) screen, hold down the ALT key while you type N M L L. The bars change to digital mode. A lower number is better, and anything between -90 to -50 dBm is good.
• To get the signal bars back, repeat the process: hold down the ALT key while you type NMLL.