Nasalgoat is 100% right. The battery(ies) do nothing when the car is running. It is the alternator's job to supply power from that point on.

However, how about this thought... Would a 1/4F or 1/2F capacitor, like you see on large stereo installs, provide power long enough to keep the unit running? I'm not an electrical wizard when it comes to calculating figures, but a large capacitor would definitely dampen the voltage drop, possibly to the point that the unit will never see it. Should that work, the only other problem is locating the capacitor somewhere. 1/2F caps are kinda big and you want to protect its leads against a short.

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Shawn Poulson
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