ATmega328PB Component Tester with Zener and LC Measurement

Developed, assembled, programmed, tested, and documented a complete ATmega328PB/Arduino Nano hardware implementation based on the open-source Markus 1.49m component-tester platform. My contribution includes ST7735 display and encoder integration, a 15-45 V DC-DC stage for high-voltage Zener-diode testing, a discrete-transistor high-sensitivity LC-meter circuit, custom PCB layouts, BOM preparation, Arduino Nano hardware modifications, firmware configuration, and source-level changes to the LC-meter control and zero-offset logic. The gallery shows the full schematic, LC-meter schematic, PCB dimensions and placement, copper layers, and a real MOSFET measurement on the completed device. The original Markus platform and upstream open-source contributors are credited; the additional circuits, implementation, PCB work, firmware adaptations, assembly, and documentation shown here are my work. - [OSHWLab: design files](https://oshwlab.com/995uet/transistortester_1-48_arduini_nano) - [Google Drive: source package and documentation](https://drive.google.com/drive/folders/1QQZMaKt_NNPciZKBD_2k7DDPdrnQSZxN) - [YouTube: demonstration 1](https://youtu.be/RA0kXC0snyI) - [YouTube: demonstration 2](https://youtu.be/JKyrUbSgpiQ)