Thomas McGahee wrote:

> See the attached PDF file for a very simple constant current source
> that might work for you.

  That or the two-transistor version beat the pants off the LM317 or
constant-current diode suggestions (the latter if only as they are hens
teeth at higher currents, though minimum voltage drop is also higher).

  Tom, why must you post PDFs?  GIFs inline into the mail much easier so
we can see them straight off in the navigator.  Your PDFs appear to
incorporate GIFs, including text, anyway.

  Your other suggestion of the transformer - would be far better off
to use the second transformer to power the PIC as well I should think.
I would think though that the space needed to add *any* second
transformer would be better utilised fitting a decent transformer in the
first place - possibly a C-core or toroidal.
--
  Cheers,
        Paul B.