I agree with charging outside of the radio (any radio, scanner or otherwise). Aside from possible internal damage (which happened to me once a long time ago) when you use an external charger, the best way to go is to have at least another set of rechargeable batteries. That way you will always have charged batteries in the scanner and another set being charged, so you will never be left high and dry, so to speak. I have the Sanyo high capacity Eneloop rechargeable AAs and I use three sets. One in the radio, another set charging and a fully charged set in a small AA box ready to place in the scanner. I also recommend that you always have a few sets of alkaline batteries on hand in case you are out somewhere and you don't have the rechargeables around.
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