USBConnect 881U

It's actually a Sierra-Wireless 881U 3G GSM modem.
The settings:

user=ISPDA@CINGULARGPRS.COM
password=CINGULAR1
init1 box enter: AT+CGDCONT=1"IP,"isp.cingular"


Enter the following AT command in any terminal application (e.g. Minicom) to obtain the signal quality (RSSI):
at!rssi?

A range from -60 dbm to -90 dBm is considered adequate.

Enter the following AT command to see whether your AirCard modem is online:
at!pcinfo

Enter the following AT command to turn the radio on (if the modem is in low power mode (LPM) the radio is off):
at!pcstate=1

For AirCards modems, the power LED on the card will light up.

Enter the following AT command in any terminal application (e.g. Minicom) to obtain the signal quality (RSSI):
at+csq

The first number indicates the signal strength above -109 dBm (in 2 dBm increments). A value of 7 or higher (-95 dBm) can be considered adequate.

Enter the following AT command to see whether your AirCard modem is online:
at!gstatus?

Enter the following AT command to turn your radio on (if the modem is in low power mode (LPM) the radio is off):
at+cfun=1

For AirCard modems, the power LED on the card will light up.