Following is a list some secondary PCB design projects. I clubbed them together in a single repository on GitHub and CadlabIO to avoid creating a new repository for each of the secondary project; because that will make unmanageable clutter.
- Atmega32uc3 Prototype PCB
- FTDI chip based Programmer PCB for AVR Micro-controllers (moved here, read more)
- Comparator Board for a Line-sensor
- Pneumatic Piston Driver PCB (with PTN voltage regulator)
- Transmitter Board
- ULN2003 IC Board
- PTN Voltage Regulator PCB
Here are some PCB images for the projects listed above.