Glad to hear that you are up and running with the new Bitx40.
My suspicion is that 13.8 v may have been too much for the previous
One. I have seen a few people suggest 13 v max, though I am not sure where that number comes from. It seems like maybe the display is fried on the old Raduino. Now that you have a working rig you might be able to use that to help diagnose the old one (ie you could try putting the old display on the new raduino).
Best of luck and above all ... have fun!
Sent from my Galaxy Tab A (2016)