I am a novice in the world of circuit design. I have spent several hours googling a solution, without success. I suspect that this is an easy project for some of the participants of this forum. I need a circuit that lights one of two LEDs depending on the value of an input voltage. A blue (or green) LED lights as the voltage increases from zero to a given threshold. (It doesn’t need to light at very low input voltages.) As the voltage approaches the threshold, the blue LED begins to fade and a red LED begins to light or slowly flash (perhaps the frequency increases as the voltage increases). At the threshold, the blue LED is off and the red light is fully on. The threshold value should be adjustable, perhaps by a small pot. If the input is insufficient to light the LEDs, I will need a circuit to amplify that input and power the LEDs via a small battery. Precision is not critical. Compactness and low-cost are important. I will appreciate any assistance on this project and will be able to build it from a schematic.