Single Coil Two Transistor Boost Circuits

[Farmhand]

MarkE was right, with the little mosfet in the circuit with the logic gate oscillator the switching goes bad at about 1 volt. So to work
at under 1 volt it needs a bootstrap setup.

The printer has arrived so I can get all fixated on designing PCB's for a while. I've got NCP1400 boost chips so I can try one of those
out too.

I made a small carbon - magnesium battery and they seem to work fairly well as compared to a piece of zinc and a piece of carbon
stuck in some dirt. 1.5 volts open circuit on a cell drops to 0.8 under the load of the circuit but charges a 1.5 Farad capacitor pretty quick.
I found that the surface area of the electrodes and the spacing are big factors in the current available, the electrodes can't have too much surface area but they can be too close together with too little resistance between them for the surface area that there is.

The carbon - magnesium battery can be constructed dry then stored and activated by adding water when desired, which could be handy for some situations. eg. hiking, when weight is a concern, dry cells can be carried and water from nature can be added to make the battery active if needed. I think the carbon will last a long time and if the magnesium can be easily replaced then it's a viable source of power for light or to recharge a phone ect.

I made a very dodgy one in a pill bottle, I could have use three times as much magnesium ribbon in it. It gave good current but the
voltage dropped a lot when loaded to 0.8 volts.