Voltage monitor

This circuit provides an easy voltage monitor. The voltage to monitor is provided on the left, by a voltage divider (but could anything you want to monitor, battery, power supply, etc). The poser supply on the right creates three different voltage points (around 4V3, 2V9 and 1V5). These are used as "grounds" for three LEDs. The voltage to be monitored is supplied to the transistor and can be measured on the rail to the left of the LEDs. For each LED to light up, there needs to be enough voltage across it. The voltage steps could be diminished by using low voltage drop diodes, such as Schottky for example.