This is another Electronics software that I like and always use for my hobby and jobs. Called "Oregano", you can use it for drawing a schematic diagram and it also able to do simulation. The most important it is free to copy and install. So if you are an electronics technician or engineer, this software can help you too in order to draw schematic diagram and make simulation on it. Here some of schematic that I draw by using Oregano. For me, it is very simple and easy to use software. Be inform that this software only available for Linux Ubuntu family only and not support for Windows base operating system.
Simple power supply schematic diagram.
Voltage monitor schematic diagram.