I've been having a hard time finding a solution to this problem.
I recently ordered a 5 Volt 2Amp AC to DC switching power supply from adafruit.cc
When I connect my Arduino's analog sensor to the ground of my switch mode power supply my Arduino detects that it's oscillating.
I thought the voltage on the ground pin would always be 0 and not oscillate. The power supply on the Arduino does this properly. Why am I having this issue with the switching power supply and is there any way to to make the circuit have a consistent ground?
I don't know how useful that analog input info will be I'm more of a programmer.