Circuits/Components:
What is the difference between a capacitor and an inductor and how are they commonly used?
How do basic analog components like diodes and capacitors work?
Can you describe a voltage divider and how it works?
What measurement devices can you use to diagnose and measure analog circuits?
Signals:
What is the difference between analog vs. digital signals?
What is the nyquist theorem and how do you define a sufficient sampling rate
Transmission:
What are the three common communication protocols? How do they (I2C, SPI, UART) work?
What are the different methods of data transmission and unique advantages/disadvanages?