low volts at idle

[Christian Williams <delorean@xxxx>]

The other night I was leaving work, started up the car, and before moving,
rolled up both windows at the same time. As they reached the top, my radio
(aftermarket) rebooted. The headlights also dimmed, binacle dimmed, etc.
After letting off the window switches, everything was fine. I tried
pushing up on the window switches while I was driving and everything
seemed to be fine. I tried again at a red light and the radio rebooted.

When at idle that night, the voltmeter was at the tick below the 13
(ack!). At speed, the needle sits juuust above the 13 mark. I notice that
normally at idle (after driving around for a bit), the voltmeter shows a
little below 13.

What options should I explore? New, high power battery? The one that's in
it now is what came with the car when I bought it a year and a half ago.
Possibly a new higher power alternator?

BTW, the D-REX is quite impressive. I've seen the "before" pictures and
it's amazing that Rich got it to where it is in only 5 weeks. Great work.

-Christian