XIEGU G90 Operation Manual page 13

When the G90 uses an external power supply, in order to prevent external interference from entering the radio through
the power line or the radio frequency interference in the radio is radiated outside through the power line, we can put the EMC
magnetic ring on the power line. Install the magnetic ring as close as possible to the side of the power plug.

When using an external power supply, carefully check the polarity of the power cord and do not
reverse the polarity.

The limited warranty of this radio does not include damage caused by an external power
connection error or damage caused by improper power supply voltage.
11
Operating
The power cord wraps around
the magnetic ring 2 turns.
As close as possible to the plug.