Group/Channel Encryption Key
Key Zero
All cryptographic keys can be zeroed (erased from radio memory) by pressing the MONITOR/CLEAR button and while still pressing this button, press and hold the OPTION button. Press both buttons for 2 seconds. A series of beeps will begins at the start of the 2 second period and then switch to a solid tone after the keys have been zeroed. The display will indicate "KEY ZERO."
If the cryptographic key(s) are zeroed, one or more keys must be transferred from the Keyloader into the radio before private communications may continue.
Private Operation
Receiving an Encrypted Call
When receiving, the radio automatically switches between clear or private operation. If the transmission being received is an encrypted
transmission, it will be decrypted, the 
icon will turn on, the receiver will unsquelch and the message will be heard in the speaker. For this to occur, the selected group or channel must be programmed for
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