[L] just finished building this intervalometer and his verbose documentation of the project has a little bit of everything. The fabrication uses common prototyping materials, and simple skills that are easy to master even for the beginner.
The hardware is based around an ATmega8 microcontroller. After snooping around the Internet [L] wanted to see if the voltage divider based focus and shutter commands that are present in some camera remote shutter controls would work for his model. Investigation with a commercial shutter release showed him how it was done, so he incorporated that into his design. When it comes to firmware for the device we really like his explanation of the menu system. There’s a lot of settings and he did a great job of planning the user interface to make them all work on the finished product.
The schematic and board layout were done with Eagle. During the layout process he made choices for easy assembly using strip board, and even walks us through the steps when cutting the traces and adding jumper wires. It’s nicely finished in this clear plastic case and demonstrated in the video after the break.