* Press (MON/F) then (0) SET to enter set mode.
* Rotate DIAL to select menu item (Basic Setup #10: LOCK MODE)
* Choose (Main) or (Sub) key to choose between option:
KEY  Just front panel keys are locked
DIAL  Just top panel DIAL is locked
KEY+DIAL Bothe dial and keys are locked
PTT Just PTT is locked
KEY+PTT  ...
DIAL+PTT  ...
ALL  locks everything
* After selecting, press PTT to save setting.
* To activate, press and hold TX-PO-LK for 2 seconds
* To cancel, press and hold TX-PO-LK for 2 seconds