That would monitor the battery and LED be green till the
battery went below, let's say 9-10V?, then red. The smaller the circuit
the better and of course should take as little power from
the battery as possible! Looking for a schematic?

Thanks!

"PinkFloyd43" <pinkFloyd43@hotmail.com> wrote in message
news:5tWrj.3258$qV2.2374@trnddc04...
> That would monitor the battery and LED be green till the
> battery went below, let's say 9-10V?, then red. The smaller the circuit
> the better and of course should take as little power from
> the battery as possible! Looking for a schematic?
>
> Thanks!

http://www.customdynamics.com/LED_battery_gauge.htm

"PinkFloyd43" <pinkFloyd43@hotmail.com> wrote in message
news:5tWrj.3258$qV2.2374@trnddc04...
> That would monitor the battery and LED be green till the
> battery went below, let's say 9-10V?, then red. The smaller the circuit
> the better and of course should take as little power from
> the battery as possible! Looking for a schematic?
>
> Thanks!

If instead of buying, you feel like building, here is a schematic you can
use:
(view in fixed font, like courier)

inV------o-----------o---------------.
| | |
| GREEN V -> RED V ->
| - -
| | |
| | |
| .-. .-.
| | |1k | |820
| | | | |
| '-' '-'
| | |
| o------. |
.-. - | ||-+ 2N700x
10k| |<---------^ | ||<-
| | |TL431 '-----||-+
'-' | |
| | |
GND------o-----------o---------------'
(created by AACircuit v1.28.6 beta 04/19/05 http://www.tech-chat.de)

You need a TL431, which is a shunt regulator, and a 2N7000, which is an
N-Channel MOSFET. The circuit measures the input voltage, and as long as it
is above 9V, it will display the green LED. Once it drops below 9V, it'll
display the red LED.

You will need to adjust the 10k pot to tell it when to switch over. At 12V,
the voltage into the reference terminal of the TL431 should be 3.3V.

Have fun.

bob monsen