As I read the instruction of Mini OSD, it only can monitor 3S voltage. However, there as many guys used 4s-6s lipo on their copter, I am using 4S as well. Could the Mini OSD monitor this voltage?
I thought No.
So, could we modify the hardware to monitor these higher voltage? and how?
jDrone is currently selling these kind of OSD but it is clone one, I would like to use 3DR Mini OSD.
Therw will be soon another board available that can support external input.
Voltage divider, 2 resistors - Yes, it's that easy.
But, you should be using the APM to read the voltage (not the OSD directly) and it speaks to minimOSD via mavlink. So in other words, the OSD doesn't measure anything. All it does is read the mavlink data coming from the APM and put it on the display in human readable text.
Again, this OSD right? http://store.jdrones.com/jD_MiniOSD_p/jdminiosd10.htm
Instructions page http://code.google.com/p/arducam-osd/wiki/minimosd
Right in the title it tells you is reads the mavlink data, so again, the APM is doing the measuring :
APM instructions for voltage measurements (note APM 2.0 is near the bottom)