hello, I was wondering if it is possible to take this:
- posted
18 years ago
hello, I was wondering if it is possible to take this:
Nope. Well, let me change that - yes if you know how to modify the charger. So it might as well be nope.
But - you can build a charger with three parts: a 12 volt DC wall wart, an LM317 and a resistor.
------ ----- Wall +|---Vin|LM317|Vout---+ | ----- | Wart -|-+ Adj [R]
------ | | | | +----------+-----> To NiCd + terminal | +------------------------> To NiCd - terminal
R is computed as follows:
First, your pack is rated in mAh. Divide that mAh rating by 10000 and call it X. R = (1.25/X) + .5, rounded up. For example, say your 7.2 volt pack is rated at 1000 mAh. That makes X = 1000/10000, or .1 Subsituting, R = 1.25/.1 +.5 or 13. Since a 13 ohm resistor is not standard, you can make one with a 10 ohm resistor and 3
1 ohm resistors in series. Use 1/4 or 1/2 watt resistors.That gives you a 14 hour charger. When your pack runs down, put it on the charger overnight and you're good to go.
If you're not into building, perhaps someone can recommend a 7.2 v charger.
Ed
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