83
The Menu
DMSCK is Invalid — your MTM800 cannot work encrypted in 
DMO. Please call your Service Provider to restore SCKs to 
your MTM800.
Covert Mode (  3 8) 
From the main menu, select 
3 Security – 8 Covert Mode.
Set Covert Mode to On
Select On. All tones are set to off, and the 
backlight and the LED are disabled 
immediately. 
Set Covert Mode to Off
Select Off. All settings for tones and backlight are restored. 
The LED is enabled and the message Covert Mode Off is 
shown.
DMO SCK (  3 9) 
Once in the menu, select 
3 Security–9DMOSCK.
Key version is displayed when you select the option.
Air Interface encryption provides service confidentiality 
between your MTM800 operating in Direct Mode and another 
terminal or a group of terminals operating in Direct Mode.
You can change the current key, if the key change operation 
is allowed by your Service Provider.
To change the key, if not in a call, select Next. The display will 
show the following message: Change to version...
•Select Yes to change the key. Key version changed 
display will appear.
•Select No to leave the key. Key version display will 
appear.
The audio is further more routed to the external loudspeaker 
until the loudspeaker is switched off. It is recommended to use 
e.g. a Telephone Style Handset in Covert Mode.
Menu
1 On
Back
Ok
2 Off
Menu
6815321H01_KOR.book  Page 83  Thursday, November 13, 2008  8:06 AM