Here is a yet another hybrid SE, this time combining the principle of the
Miller Engine with the Chloroplast SE. Two versions are shown with the top
one using a Darlington transistor and the bottom using 2 separate NPN
transistors which have a lower "on" voltage and deliver slightly more power
to the motor. Both MS Chloroplast SE trigger at 4.8V and reset after a time
determined by C2. The value of the main storage cap C1 can be 10,000uF to 1F
and the value of timing C2 can be 1uF to 100uF.
This SE design can also be used with the 3V MC34164-3 chip, 3.4V solar cells
and 2.5V super caps for a lower voltage applications (2.8V).

wilf