The “5 Bar” signal level display, at the top right corner of your 8820 display is, “cute,” but of little practical use as it is too vague and insensitive. With a more accurate, and sensitive way to indicate signal power, you can experiment with “how” you physically “hold” and use your BB, try an external antenna in remote locations, keep a “handle” on receiver sensitivity, etc.

A far better way to indicate cell tower signal strength is to display the actual signal power in “dBM.” This is the signal power level, in decibels, referenced to a signal power of 1 milliwatt. The level will ALWAYS be a “negative” number as your signal level will always be less than 1 milliwatt, much less.

To change your display from “5 Bars” to signal power in dBM, do the following: With one finger, hold down the ALT key on the far left. Now, with your other hand, press the letter sequence NMLL. Your display should instantly change from “5 Bar” to signal power in dBM. To revert BACK to “5 Bar,” do the same thing again.

There is ONE CAVEAT in doing this. An extremely WEAK signal, less than or equal -100 dBM, will NOT show on-screen becuz only 2 digits can be displayed. So, when your signal level gets VERY VERY weak, at, say, -99 dBM, a further drop will change the display to “-10,” then “-11″ etc, corresponding to signal powers in the -100 to -119 dBM range. This is of no real problem tho, as your phone probably wont work at that low a level anyway, BUT you can experiment with an iinduction coupled external antenna if you want. Also, it is highly unlikely you will ever see a signal level HIGHER than about -40 dBM, i.e. -39, -38, yada yada, dBM.

For those who are technically oriented, as most BB Users are, and want MORE, here is an approximate tabulation of the # of Bars vs. signal level in dBM:

• 1 bar ~ -102 to -120 dBM
• 2 Bars ~ -93 to -101 dBM
• 3 Bars ~ -87 to -92 dBM
• 4 Bars ~ -78 to -86 dBM
• 5 Bars ~ -40 to -77 dBM

Ed note: This works on ALL Blackberry models