use vbat vbat_offset to Accuralte battery Vol - jumbo77/NanoVNA GitHub Wiki

serial connect to comx 9600bps

NanoVNA Shell

ch> help

Commands: version reset freq offset dac saveconfig clearconfig data frequencies port stat gain power sample scan sweep test touchcal touchtest pause resume cal save recall trace marker edelay capture vbat vbat_offset transform threshold help info color

ch> vbat

4533 mV

ch> vbat_offset 133

ch> vbat

4137 mV

ch>saveconfig