Just a hunch, I am not sure what normal is there. I am actually kind of surprised that its that noisy normally.
I don't know if I ever probed a DMM voltage rail, I figured it would be whisper quiet.. but I suppose it does make sense with a simple resistive load of 1.5A this low noise lab supply is already at 3mVrms. *
actually no, its the current limit, I need to find a better resistor, I got curious about the load noise profile on my power supplies since you mentioned it. It only gets noisy when it gets into current limiting.
ok so it looks like it wont happen with load alone, it has to be the chips, up to 1.5A, so long I stay in CV mode, the ripple is still less then 1mV, Not sure how well a 317 does in comparison, but if its EMI its EMI.
Does that one even use a 317? i guess its too big for it