Just a quick post for those who may be trying to get the OSD voltage on the Foxeer Arrow CCD camera.
You can run power straight from the battery to the camera (5-22v) and it will display the voltage but the manual suggests a regulated voltage for the input, especially if you have active braking enabled. So running regulated voltage to the camera is recommended, but now our OSD voltage will be a constant voltage and not reflective of the sources voltage.
To get around this you need to remove the back cover, revealing the circuit board. Just below the positive terminal of the plug you will see two copper tabs/perforations, marked + and –
Run two tiny wires from these tabs through the hole on the front of the case and route them to your source voltage on the PDB. When these wires are connected it will display voltage from here by default.
Happy voltage monitoring.