Hytera TC-580 - Manual (Page 21)

5
Basic Operations
To receive, just release the PTT. When a signal is re-
ceived, the LED solidly glows green, and the icon
appears on the display.
Locking/Unlocking the Keypad
Locking the keypad can prevent accidental keypad
operation.
To lock or unlock the keypad, press and then
immediately.
Note:

To ensure optimal volume of the receiving
radio, hold the radio approximately .5 to
5 centimeters away from your mouth.
 Communication range may get affected
in rainy days or forest locations.
Note: When the keypad is locked, the radio
can also respond to the keys PTT, SK1,
SK2 and TK.