I’m guessing that this is to do with the fact that you aren’t using a proper FTDI and that you aren’t getting a proper power/ground supply to the TTL/USB adapter when not powering it from the PC.
However, your screenshot shows a baud rate of 9600 but my code uses 74880 for the serial monitor.
Sometimes. It requires the output of the Tracer to be set to a certain setting, and these aren’t very intuitive.
As you’ll see from my PCB, I’ve started using a 2-way relay board that is connected to D6 and D7, so I mostly use that approach now.
Glad you’ve had some success anyway!