I'm wondering if anyone would have an idea of the size and rating of a capacitor I might need. OR, know of a good electronics site I might post this I have a 69 Dodge Charger. I upgraded the radio to a modern CD player. My problem was that every time I came to a stop, the CD player would shut down until I hit the accelerator again. It turned out the old style alternator couldn't deliver a constant 13.4 volts at idle (low RPMs) which is what the CD player required. My solution was to install a capacitor in parallel to the power supply to the CD player which increased the voltage enough at idle to keep it from shutting down. Now I have a 1991 Suburban with a rear power window that operates very slowly (sometimes stalls) when the engine is off, running of the 12 volt battery.. It works well when the vehicle is on and the charging system is putting out 13.4 volts. I wanted to install a capacitor at the rear widow motor to increase the voltage but am not sure what size or rating I'll need. I'm thinking the motor probably draws 10 to 15 amps (I can test if necessary). Anyone have any ideas? Thanks, Eric M.