R/C Battery charger with capacity indicator

[fjpompeo]

I need a circuit of a R/C NiCd/NiMH pack battery charger with capacity indicator, I mean how much mAh the pack was charged. My packs are 7,2V x 2200mAh NiCd and 7,2V x 1800mAh NiMH used to power the servos of a helly.

Regards,

Fernando - call sign PU2PLL

 

[SAR]

Try these;

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This one in japanese use bablefish to translate: http://www.picfun.com/appframe.html

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[metal]

Hello

You can calculate the capacitor value using this relation :

C = I / (6.28 x F x V)

Where I is the current needed to charge the battaries, F is the mains frequency, and finally V is the mains voltge 110 or 220.

A rule of thumb here is that the current needed to charge a battery is usually 1/10 of the battery capacity.

Sometimes a resistor is used in series with the capacitors, this resistor valus is better made equal to 1/10 of Xc of the capacitor.

Xc = 1 / (6.28 x F x C)

Regards