I am filling out a questionaire for the aforementioned headhunter.
I am struggling with a question: "What are your top four skills."
Ask yourself that question. What are you actually skilled in? Rank them from one to four. I can name lots of things that I am "skilled" in, but I can name only two that I feel are relevant to the job market: digital electronic design, and Linux.
Perhaps just having the basics of the skill is enough: test equipment, soldering, programming, RF propagation, antenna design (but that would be a stretch).