Telephone engineer explanation

My husband is a telephone engineer and when our second grader asked him to speak at Career Day so that he could explain to the class what the job was, I was anxious to attend.  To be honest, I’m not entirely sure what he does.  I know that he spends a good part of the day drinking coffee and glaring at diabolical looking things on his computer or sketched out on graph paper.  It boggles my mind.  I really think that I could use a child’s version of the job description.  He started with explaining that he creates different kinds of communication for different purposes such as science or industrial or commercial use. He must have recognized the blank stare on the sea of faces as being similar to the one that’s usually on my face, because he went to Plan B, which involved a soda can and pipe cleaner.