Current Flowing Indicator.

[pwdrive]

Thanks for the drawings and explanation Al, it has made things clearer for me now.
So if I have got this straight the difference between Joe's full wave doubler circuit and the more conventional full wave double circuit is that in Joe's the voltage doubling is effectively due to a series combination of the transformer secondary voltage and the charge on the capacitor where as in the more conventional circuit it is due to the series combination of the charges on the two capacitors.
In Joe's experiments the former method outputs a lower voltage where as the latter outputs a higher voltage.

Lawrence.