I would like to have the meter on only during a short time. I wish to use the connected battery for the self supplied power for the display. I would like to use a power mosfet and a photo electric cell ( 4 v ) across the gate source to switch the meter power on and off. I will use a flashlight on the photo cell to remotely turn on the meter on when I want readings.

What mods do I need to make to implement this?

Regards  Del         Design engineer