>
> >>
> >> When caught with a dead battery and no trickle charger I find putting a 7
>1/2
> >> watt 120V bulb in series with the battery and charger and leaving it
> >> overnight gives a good trickle. No clue what the actual current is.
> >>
> > somebody stop me if I've dropped a decimal somewhere, but it looks to
> > me like this would limit current to about 6ma even if the battery was
> > shorted. This seems safe enough, in fact hardly enough to do any
> > good. phile@pwcs.stpaul.gov
> > --
> > Login name: phile In real life: Philip J Ethier
> > Phone: 298-5324
> >
>
> As long as there's not enough current going through the bulb to light it up,
> the resistance is drastically different. I'm not sure if its higher or lower,
> but if it charges a battery I guess its lower. In beginning electronics class
> we once built an oscillator that was voltage stabilized by using a little
>light
> bulb in series with something. It seems that the current-resistance curve of
> an incandescent light bulb was perfect for that application. Maybe the
>battery
> charger limiting works on the same mechanism.
>
> Joe
>
Yes, I did forget about that. I suppose a guy should measure the
resistance of the bulb cold to figure this out. I think it is LESS
than when hot. I'm sure that the bulb will never heat in this
battery-charging use. phile@pwcs.stpaul.gov
--
Login name: phile In real life: Philip J Ethier
Phone: 298-5324
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