back EMF III
Because of enormous production of heat in previous setup (breaking contacts simple can’t withstand it) scaled down schematic to 6V battery, made mechanical switch running independently from 1.5V battery (on this scale it’s easy to adjust and maintain), and connected to 7.2V electric motor instead of bulb. Main source of back emf – heavy coil of one side of transformer. Good news is – the system runs about 3 hrs without voltage drop (compare to instant voltage decline if running without coil). Actually what’s going on here – back emf spikes of hi-voltage fired back to battery and slowing down process of chemical sulfitation what keeps the battery charged. Wondering if it will work with bank of good ultracapacitors instead (or in parallel) with battery.