You absolutely can charge the batteries inside the radio while it’s operating. I do it all the time.
This is a solid radio yes older. I run it right next to my SDS100 and it keeps up. I do wish the SDS100 and SDS200 had the touchscreen that the HP2 has, makes operation really simple.
Came with a nice little guide for instlallation. Works great
Really love the way it protects the screen. Finally found a supplier for my SDS200
Screen protector worked really great expecially with my grandkids that scratch and touch everything.