Purpose was to gauge overall understanding of electrical engineering undergrad degree. Starts simple then works up to advanced concepts until you begin to struggle. At this point they dig in and began to ask conceptual questions that required extending general undergrad knowledge, ie what is capacitor self resonance? Not taught in undergrad generally, but obvious if you understand basics. Being flown out to Seattle is cool for an intern interview.

I am currently an junior in EE at Caltech. I had been an Explore intern the summer before, so I was able to use my campus recruiter contacts to help initialize an interview process quite early in october. Being an explore intern before, however, didn't really give any more advantages than that. I had only done basic software and the position I was looking for was in hardware (which was my real interest and passion). The interview process was longer than that of the Software positions. Instead of 3 back to back, we had 4 -5 interviews back to back. All of us were placed in a large conference room and people were just being called out one by one. The most competitive school that other candidates were from, that I can remember, was Carnegie Mellon and possibly UC Berkeley. It might have just been that I was at a very early interview round. Each interview was from someone of different team from popular products. The questions very different as well ,ranging form basic analog, and Digital, to basic signal processing. There were no software questions.