This article is from the Motorsport FAQ, by A H Henry bspahh@midge.bath.ac.uk with numerous contributions by others.
Longer lasting batteries or spare packs come in very handy for long
race weekends when there might not be time to recharge the standard
battery.
Most if not all portable scanners have an external power connector,
usually 12V, so you can plug it into your car cigarette lighter. You
could also make a battery box for 8 "D" cells to connect to the power
jack.
 
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