OpenGD77

Did today some measurements at the GD-77 Battery, it seems that the displayed voltage in the batteryscreen is not very accurate.

In my case the radio shows 8,0V, the real battery voltage is 8,3V (measured with a calibrated DMM). In my opinion not fatal, but results
in slightly dissenting levels for example at the low batt warning.

Did you measure the voltage actually at the CPU. The voltage on the external terminals of the battery is not what the CPU gets, because of the internal power control electronics

I measure at the battery direct, hence the end of discharge voltage and the end of charge voltage are dependent of the voltage at the battery.