Schematic Diagrams

Notes on the diagram

How Q2 and Q3 form an inverter on the PCB

Get the schematic

The tool used for this is gSchem, part of gEDA. If you are running Linux, it's highly likely that gSchem is in your distro's repository - on Fedora, it's just a matter of using Applications -> Add and Remove Software, and then selecting it from the list of applications (use the Search facility to look for 'gschem'). It'll be automatically downloaded (bizarrely, it ends up in 'Edutainment' on the Gnome menu - don't ask me why!) It can also be started by typing 'gschem' in the shell as well.

gSchem downloads for other platforms can be found at the gEDA website


See the Components page for some component subsitution and omissions suggestions. For example, the inverter formed by Q2 and Q3 can be replaced by a single N-channel MOSFET and a 1K resistor if you're making the board on strip board and don't fancy trying to solder SOT-23 packages. Q1 can be replaced by a bipolar NPN transistor and base resistor too.