Einleitung
Find out what makes a cordless drill/driver whirr.
Werkzeuge
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The driver kit.
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This is a more-or-less no-name cordless screwdriver/drill kit, but its construction more or less matches most of these devices.
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The charger consist of a standard wallwart, output 14.4V 350mA, along with a little block (weighing nothing at all) to connect to one of the battery packs.
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To open the charger block, unscrew three #1 Phillips screws.
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After lifting off the bottom, the PCB is exposed, and you can lift it out of the charger block along with the battery contacts. On the PCB we find:
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A diode to protect against reverse current.
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An LED and resistor that is on so long as the box gets power.
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A giant 10 Ohm resistor to slightly current-limit the charge, and across which the green led and resistor are placed -- this will therefore light up as long as significant current passes to the battery.
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After removing the screws, turn right side up again and lift off the plastic cover, exposing 12 NiCd cells in a string, and nothing else.
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Note that there is room on the right side for three more cells, which would make a 18V battery pack.
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Especially cheaper makers usually have versions for 7.2V/9.6V/12/14.4/18V all using the same plastic, just more or less cells and a different motor.
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