Audiovox GSM/GPRS Compact Flash Card RTM-8000 Owner's Manual page 51

Tap Dialer.
If the PIN code of your SIM card is enabled, you will be prompted to
enter it. Enter your PIN code and tap OK.
Note: If you entered wrong PIN code three times in a row, the SIM card will be
blocked. In order to unblock the SIM card, you have to enter the PUK-
code of your SIM card. Contact your operator to unblock it.
Using the RTM-8000
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