Saw this and liked it: http://www.circuitstoday.com/car-bat...cuit-using-led
Question is, if I have 3 LM324s, what resistors do I need to change [and add] to get the following voltage readouts on the output pins of the comparators? Assuming all resistors can be set to exact values using trimpots
I'd go with an A/D convertor and use digital decoding to light the 12 LEDs.
Another way is to use a 12.0v electronic Zener to make an expanded scale analog voltmeter. Much simpler circuitry; one trimpot, one Zener, one meter movement but you have to hand-draw the meter scale face.