This is measured in dBm with a practical range for us of -100 to -40. The lower the negative number the stronger your signal is. Here's a chart illustrating this:
You can check to see what your signal level is by moving your mouse cursor over the signal bar graph in the connection manager. Don't click a button, just move the cursor over it and the dBm number will show.
On the Sprint Connection Manager and VZAccess connection manager the signal level is shown right on the main interface.If your signal is in the -70's you will likely be getting the maximum EVDO speeds you are capable of, barring any hardware issues you may have. Throwing gobs of money on amplifiers and cables to get it into the -60's range is not going to gain you much, if anything. Cell towers in urban areas are often fed by two or more T-1 lines whereas rural areas are fed by one T-1. A single line will give you a max speed of about 1.4 MB/s (allowing for cell company overhead). Multiple T-1's will give you 2 MB/s plus. In other words if you are out in the middle of nowhere don't expect the kind of speeds our urban brethren are getting.
