Solution from Manual (Section 15.2):
The manual complies with WEEE (Waste Electrical and Electronic Equipment). The R4.0 lithium-ion backup battery (for clock/RTC) must be removed before recycling – a procedure requiring soldering iron, thus "Return to Hytera-certified center only." hytera mt680 tetra mobile terminal owners manual r4 0 new
Before you flip to the Installation chapter of your manual, identify your R4.0 unit. The owner’s manual highlights these physical identifiers: Solution from Manual (Section 15
Pro Tip from the Manual: Never hot-plug the rear connector. The R4.0 manual explicitly warns that doing so may trigger a transient voltage spike that resets the terminal’s volatile memory. Before you flip to the Installation chapter of
Solution from Manual (Section 6.4): The orange button has two modes: Hot Mic (transmits ambient audio) and Emergency Alarm. The new manual clarifies that to reset an Emergency Alarm, you must power cycle the terminal for 10 seconds—simply pressing the button twice no longer works in firmware R4.0.