Hi, i've finally put that circuit and pictures up for
the super cheap 2-transistor switchmode 5v regulator
that Richard and Russell and many others contributed to
a few weeks back.

There are a couple of charts of efficiency and regulation,
and the circuit and CRO waveform. Also a great picture
of my quick coffee-table "lab setup" ha ha! :o)

It's all public domain and may be of use if you need
to run a 5v or 4v PIC from a battery with double or
triple the efficiency of a 7805 linear regulator, and
on a very tight budget. All parts are discrete and
non-critical, even the inductor, so you can use any
cheap mass produced pre-wound inductor and still
get good results.

Here it is:
http://centauri.ezy.net.au/~fastvid/smps.htm
(there are a few small pictures, about 200kb
total)
-Roman

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