> The unloaded voltage is 40V, with a 2200u cap attached it tops out at
> 24V.
> It reaches this in just short of a minute and reaches 20V in less
> than 30 seconds, which is OK for 30 and 60 second clock movements.
> They'll pulse alright with just 1000u so there's some room to play with.
> Russell suggested a R/Zd on the output to feed back to the PNP base
> but in my case that won't be necessary

Amount of energy transfer and therefore peak voltages and charging rates can
be altered by using different inductor size and/or oscillation frequency.
Due to fairly massive interaction of several factors its a bit of a "try it
and see" circuit.
For anyone trying this - the inductor can be one of the small 1/4w resistor
sized chokes sold mainly for RF purposes.
Should be an OK cct for eg 12v supply for programming.




        Russell.

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