> > *>But I've used a 1uF capacitor in RM's circuit - which blinks at about
> 1-5
> > *>Hz.  This is my frequency isn't it?
> >
> > Not quite. If you refer to the core, it has to do with the switching
> > frequency, not with the blink frequency. I hope that I understood what
you
> > asked ...
> >
> > Peter
>
> I think I'm wondering whether the two frequencies are the same.  I went
back
> and reread RMs comments

My circuit is unusual.
It doesn't HAVE a switching frequency per se as there is only one cycle per
LED flash BUT it is a large one - ALL the energy is transferred in one
inductor charge/discharge cycle. The two therefore ARE the same but you
design the inductor for the short length of the actual energy pulse - not
the long time between pulses.


        Russell McMahon

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