NARDA NBM-550 - Locking the Keypad

4.3 Making basic settings
Narda NBM-550 41
Locking the keypad
To prevent inadvertent operation of any of the keys, you can
lock the keypad.
Locking the keypad
 Press the two arrow keys ▲/▼ simultaneously.
 The message KEY LOCK is displayed.
Unlocking the keypad
 Press the two arrow keys ▲/▼ simultaneously again.