Baofeng BF-T8 - Combination key function

Description of the Buttons
03
Combination key function
Call Tone: Press and hold [PTT] button and[MONI]button to transmit 1750Hz
tone signaling,Release the [MONI]button to exit;Press and hold [PTT] button
and[FM]button to transmit 1450Hz tone signaling;Press and hold [PTT] button
and[ ]button to transmit 1750Hz tone signaling.