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Old Aug 10, 2011, 12:27 PM
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United States, MA, Walpole
Joined Dec 2003
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Originally Posted by picard10th View Post
I read that and you got approx 100 min more with external pack. I get no more time and it starts buzzing within 50 min so I actually get less quality time with the external. Sup?
My external battery pack has four 800 mAH AA cells in series, so it can deliver the full 800 mAh capacity to the camera at a nominal 4.8V. As the FAQ's explain, the emergency charger with just ONE cell has a voltage quadrupling circuit to get proper voltage to charge the camera internal battery. In so doing, the available current the battery can supply is REDUCED by the same factor of 4, with also some efficiency losses. The bottom line is it only has enough current available to slowly charge the camera internal battery while the camera is NOT also recording). When the camera IS recording, the current demand goes way up and the emergency charger cannot sustain that current level for very long without dropping it's voltage to the point where it can no longer power the camera. At that point, the camera internal battery does all the work, so the emergency charger can only add maybe 15 minutes or so of additional recording time.
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