phD Electronics is a semiconductor cross-reference application primarily designed for engineers, technicians, and electronics hobbyists. The program lets you search its extensive database for equivalent and similar transistors and diodes, given the code of the original one. It contains thousands of semiconductors, including zener diodes, transistors, and rectifier diodes, and includes a simple text editor. In addition, you can display the value of resistors and polyester capacitors based on their color codes\; get repairing hints\; and edit and back up the database.