>>
>> 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
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