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 # Main features:
  - OneOfEleven mods, including AM fix
  - fagci spectrum analyzer (**F+5** to turn on)
- - better battery percentage calculation (based on real measurement)
+ - better battery percentage calculation (based on real measurement, battery calibration recommended)
+ - battery calibration option available available in the menu (instructions below)
+ - there is no FM radio nor Aircopy, not enough memory space
 
 <img src="images/main.jpg" width=300 /><img src="images/spectrum.jpg" width=300 /><img src="images/audiobar.jpg" width=300 /><img src="images/rssibar.jpg" width=300 />
 
-❗❗❗Battery calibration is highly recommended, the calibration is firmware independent and persistent:
- - https://github.com/amnemonic/Quansheng_UV-K5_Firmware/tree/main/python-utils#batt_calibratorpy
+❗❗❗You can now calibrate the battery voltage reading in the radio menu. 
+
+<img src="images/batcal.jpg" width=300 />
+
+To enter the calibration:
+
+1. turn the radio on holding PTT and the first side button 
+2. imediately go to BATVOL option and adjust the voltage with UP/DOWN buttons
+3. confirm the setting, calibration will be saved to EEPROM
+
+The calibration option becomes unavailable if you leave the menu screen and you have to repeat from step 1.
+
 
 # Open reimplementation of the Quan Sheng UV-K5 v2.1.27 firmware
 
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