I threw together a simple constant current source shown below. I did something stupid but can't figure out what.
If I use a single power supply to power the MOSFET/OpAmp input it works fine. But if I have a separate power supply for the input and another for the MOSFET drain/source output it doesn't work. The MOSFET won't turn on.
BTW, this isn't an LTSpice question (both work fine in LTSpice), it's an actual breadboarding question. And I'm sure the breadboard wiring matches the diagrams in both cases.

Anyone?
Thanks.