79
The Menu
Locking/Unlocking the Keypad 
To prevent accidental key/button presses:
1.
Press   OR,
From the main menu, select > Security > 
Keylock. The 
keypad is locked except .
2. To unlock the keypad, 
press  .
Air Encryption On/Off 
From the main menu, select > Security > AirEncrypt.
This sub-menu allows you to view air encryption On/Off state.
Call encryption provides service confidentiality between you 
and the system.
If encryption is on and you receive a clear call (unencrypted), 
the 
 MTH800 will display a Call & Data Not Encrypted 
message.
When there is an incoming call and the keypad is locked, you can still use 
the PTT, rotary knob, , and
.
The Emergency button is not locked. Entering Emergency Operation, 
unlocks all keys.
You cannot manually disable Air Encryption (if fitted) from the menu. This 
sub-menu only indicates if Air Encryption is enabled at that moment.
The Air Encryption feature is ONLY enabled depending on your Service Pro-
vider.
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6802972C35.book  Page 79  Monday, August 16, 2004  9:22 PM