Looks like RF got into your arduino board.
I suspect your RF termination is not proper even though you stated you are using a dummy load.
I was doing the same but had RF all over, found later that the braid of the BNC to load was frayed.
After I replaced it all problems vanished!
At 15/07/2017, you wrote:
Let me back up again:
My kit came with something like 1.0 or 1.1 already installed on the nano. Right out of the box my Bitx would receive fine but not transmit. While I was waiting to try and resolve the transmit issue I uploaded 1.18 to the nano and used the radio on receive for a few days while I asked some questions. Someone mentioned that the RV1 and R136 would increase the output if turned to the left rather than turned to the right. I had only been moving them from what appeared to be near the center position to the right. So I put a dummy load/power meter on it the other night and instead of using the 12v 1.5a wall wort supply that I had been using I switched to my Samlex 13.8v power supply. I turned to power on to the power supply. Plugged the radio in and turned the radio on. I keyed up and was watching my power meter and speaking into the mic to see if adjusting either pot would give me some kind of output. While I was doing that I just hapoened to look at the display and noticed that it w
as still lot up buy I had black squares across the top row of the display and no longer any text. I powered the radio back down and up again and the display stayed that way. So I thought maybe something happened and the Arduino lost its mind. I unplugged the radio from the power supply and decided to see if I could upload to the Arduino. I could not. I unsoldered the Arduino tonight and noticed that C17 looks like it had disintegrated from the board. So I have some new Arduino coming on Sunday.
Raj vu2zap