samsung mobile test mode3:

Samsung A560, A740, A760, A840, A880, P207
Enter ## 33284#, press OK. Enter security code 040793. Select DEBUG SCREEN and press OK. Signal strength is 2nd number on 2nd line (for example, T-XX Do XX -05). To exit, turn off phone...

Samsung A790
Enter ##33284#. Enter Service Code, 040793. Signal strength is after the D. To exit, turn phone off...

Samsung A740, A850, A930, A950 U740 A870 (Verizon)
Press MENU (blue center button). Scroll to SETTINGS & TOOLS (tools icon) then press the # key. Enter User Lock Code, 000000 (six zeroes). Select DEBUG SCREEN. The screen will read some similar to T-63 D089. The number after the D is the signal strength, for example -89dBm. To exit, turn power off.

Samsung A900, A920 and A570
Enter ##33284# or ##33284 and press the blue OK button. Enter Field Service Code 040793 or 000000 (six zeroes). Choose DEBUG SCREEN or FIELD TEST and then SCREEN. Signal strength is the number after the D. (Note: the A900 appears to go right into the test screen after the 040793 is entered)...

Samsung E105, D807, A517, E316, E317, X426, X427, X475, S300, S307, D347 (GSM)
Enter *#9324#. Signal strength is last number on the 4th line. The number omits the negative. To exit, turn off phone.

Cingular (Samsung) BlackJack
At the home screen, type in *#0011# and the information will pop up (do not hit ok or anything else after entering key sequence)..

Samsung BlackJack SGH-I607, A412 , Black Jack II
Option 1: On the main screen press *#0011# and an information screen will appear.
Option 2: In the Windows folder open the folder called “Test Mode” and run the file by the same name. Signal strength will follow RSSI. This screen will also show the frequency which you are operating on. Simply select EXIT to get out of this screen.

Samsung i730, I760 (Verizon)
In phone mode, enter **33284 and the Security Code 000000 (six zeroes). Choose MONITOR. The receive signal strength follows R- on the screen, transmission signal strength follows T-.

Samsung N240
Enter ##33284 and press OK. Select DEBUG SCREEN and press OK. Signal strength is 2nd number on 2nd line (for example, T-XX Do XX-05). To exit, turn off phone.

Samsung U520. U340
Press MENU (OK Button) , 9, 0. User Lock Code: 000000 (six zeros). Choose DEBUG. Signal strength is 2nd number on 2nd line (for example, T-63 D085-5. This means -085 dBm).To exit, turn off phone...

Samsung U540
Press MENU, choose “Phone Settings” and press #. User Lock Code: 000000 (six zeros). Choose Field Test Mode and then DEBUG. Signal strength is on the line that says: T-XX DXXX. To exit, turn off phone......