Help me build a voltage monitor

[FlyRC4Life]

:) Hi,
I would like to build a simple voltage monitor with one LED that will connect in line with a 2s1p 250mah Lipo for use in a HLG. I will bring the voltage down with a GWS ICS speed control (and just ignore the motor connector). Or I could use a 5v voltage regulator.

Anyway, I would like the LED to glow when the battery pack reaches an output of 6v (lowest voltage safe for 2 cells) so that I will know that it is time to charge the pack. With this batt however, 4 hours of flight time should be the norm.

I am knowlegabe about Lipo saftey dont get me wrong. But im not interested in using a speed controller with a BEC.

A simple schematic would be a big help. I am not quite to the point where I could design this simple circuit on my own but I can build from schematics and know what a resistor, pot and LED are.

Thanks a lot
Alan

[everydayflyer]

There are many of these on the market and there are some D.I.Y. (how to )post also.
I am sure someone will provide link very soon.

Charles

[FlyRC4Life]

After some searching, I found a schematic for a 6v monitor but it is designed for the light to go out when the voltage drops below 6v. I would rather the LED come on at 6v but im not sure if this is more complicated than the latter.

[Rejean Boucher]

Check this site out for a simple voltage sensing cct.
http://www.electronics-lab.com/projects/models/004/
It was designed for NiCads but read through the text and you will see the formula for modifying the trip voltage.

Reg

[theoxx]

Here's another:

http://www.webx.dk/rc/lipoly/low-volt-alarm.htm