Why not have a look at Clive Mitchell's version: his uses a single
transistor and he includes pictures of how to use a ferrite bead to make
the inductor.  Have a look at
<http://www.emanator.demon.co.uk/bigclive/joule.htm>

dwayne

At 04:14 PM 10/19/02 -0500, David & Ann Scott wrote:
>This circuit from the SMPS circuit challenge of a year ago(!) is the "LED
>blinker/dead battery milker/3909 replacement" from Russell McMahon:


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Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
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