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3
APCO P25 MODE OPERATION
n
Encryption function
The Encrypton functon enables secure voce communca-
ton, whch provdes prvate dgtal communcaton between
users.
q
Push
[Encryption]
or
[Scrambler/Encryption]
to turn the
Encrypton functon ON.
• “
”
on Handheld types or “ ”
on Moble types appears. (Smple
and 10-key types only)
w
Push
[Encryption]
or
[Scrambler/Encryption]
agan to
turn the Encrypton functon OFF.
• “
”
on Handheld types or “ ”
on Moble types dsappears. (Sm-
ple and 10-key types only)
D
Key Fail Indication
The transcever ndcates “Key Fal” for the specfied tme
perod* when the Common Key Reference (CKR) of the se-
lected channel s not stored n the encrypton unt. (Smple
and 10-key types only)
D
Decryption Multi Keys function
When ths functon s enabled, the transcever releases the
mute after recevng the audo sgnals for decrypton, even f
the CKR settng s not matched to the selected channel.
* Dependng on the pre-settng. Ask your dealer for detals.
n
OTAR function
P25 Over-The-Ar-Rekeyng (OTAR) functon allows the Key
Management Faclty (KMF) to change the encrypton keys n
a transcever remotely, (“over the ar”) to protect the secure
communcatons.
Moreover, several OTAR commands are used to perform the
followng operatons.
From KMF to transceiver:
• Change Actve Keyset
• Change Group RSI
• Rado Check
- The transcever automatcally responds to any command.
From transceiver to KMF:
• Regstraton to the OTAR system
• Deregstraton from the OTAR system
• Rekeyng
- When the channel n whch the OTAR functon s enabled
s selected, the transcever automatcally attempts regstra-
ton to the OTAR system by transmttng a Key Management
Message (KMM) to KMF.
Varous other commands are exchanged between KMF and a
transcever, other than above.
Not avalable on Non-dsplay types.