Robert Nansel wrote:

> The schematic is correct, but I see now that I used a confusing
> convention for diode polarity. Thanks for pointing that out.

  No, Robert, you used the CORRECT convention in the first place.
Please do not use another!

  The plus sign goes on the cathode and corresponds to the "band" on the
body of the diode.  It indicates which side of the diode develops a
positive voltage when used in a rectifier circuit (which is what diodes
were originally used for!).  If in a rectifier circuit, you put a DC
meter across it, this side will register the positive voltage.

  Cheers,
        Paul B.